Reproduction In Organisms.pdf

01
CHAPTER
Reproduction
in organism

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- is a process in which an organism produces young ones
(offspring) similar to itself.
- The period from birth to the natural death of an organism is known
as its
- No individual is immortal, except unicellular organisms. There is no
natural death in unicellular organisms.
Life spans of some organisms
Organism Lifespan Organism Lifespan
Rose Parrot
5-7 years 140 yrs
Rice plant 3-7 months Crocodile 60 yrs
Banyan tree
Banana tree
Dog
Butterfly
Fruit fly
400+ yrs
2-3 yrs
22 yrs
1-2 weeks
2 weeks
40-50 yrs
100-150 yrs
15 yrs
22 yrs
50-70 yrs
Horse
Tortoise
Crow
Cow
Elephant
ASEXUAL REPRODUCTION
- It is the production of offspring by a single parent.
- It is seen in unicellular organisms, simple plants & animals.
- The offspring are identical to one another and to their parent.
Such morphologically and genetically similar individuals are known as
Types of asexual reproduction
• Fission: In this, the parent cell divides (cell division) into
two or more individuals. E.g. Protists and Monerans.
• Binary fission: It is the division of parent cell into two
individuals. Amoeba, Paramecium.
• Multiple fission: It isthe division of parent cell into
many individuals. E.g. Plasmodium, Amoeba.
• Budding: In this, a bud appears and grows in the parent
body. After maturation, it is detached from parent body to
form new individual. E.g. Hydra, Sponge, Yeast etc.
•Vegetative propagation: It is the production of offspring
from vegetative propagules in plants.
Vegetative propagules are units of vegetative propagation.
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Example s for vegetative propagules:
• of the potatotuber.
• of banana & ginger.
Buds & Rhizomes arise from the nodes of modified stems.
The nodes come in contact with damp soil or water and
produce roots and new plants.
• of Bryophyllum. They arise from the
notches at margins of leaves.
of Agave.
of water hyacinth.
E.g. zoospores
(microscopic motile structures in some algae and protists),
conidia (Penicillium) and (sponge).
Asexual reproduction is the common method in simple
organisms like algae and fungi. During adverse conditions,
they can shift to sexual method.
Higher plants reproduce asexually (vegetative) & sexually.
But most of the animals show only sexual reproduction�
SEXUAL REPRODUCTION
- It is the reproduction that involves formation of male and female
gametes, either by the same individual or by different individuals
of the opposite sex.
- It results in offspring that are not identical to the parents or amongst
themselves.
- It is an elaborate, complex and slow process as compared to asexual
reproduction.
- The period of growth to reach in maturity for sexual reproduction is
called the . In plants, it is known as
- In higher plants, the flowering indicates the end of vegetative phase
(beginning of
-
these phases are very
difficult to identify.
- Some plants exhibit unusual flowering.
• Bamboo species flower only once in their lifetime (after years),
produce large number of fruits and die.
• Strobilanthus kunthiana flowers once in years.
- In animals, juvenile phase isfollowed by morphological and physiological
changes prior to active reproductive behaviour.

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- Birds living in nature lay eggs only seasonally. However, birds in captivity
can be made to lay eggs throughout the year.
- The females of placental mammals exhibit cyclical changes
in the ovaries, accessory ducts and hormones during the
reproductive phase. It is called oestrus cycle in non�primates
(cows, sheep, rat, deer, dog, tiger etc.) and
menstrual cycle in primates
• Seasonal breeders: The mammals (living in natural
conditions) exhibiting reproductive cycles only during
favourable seasons.
• Continuous breeders: They are reproductively active
throughout their reproductive phase. Senescence (old age):
- It is the last phase of lifespan and end of reproductive phase.
- During this, concomitant changes occur in the body. E.g.
slowing of metabolism etc. It ultimately leads to death.
In plants & animals, cause transition between
Interaction
between hormones and environmental factors regulate the
reproductive processes and the associated behavioural
expressions of organisms.
EVENTS IN SEXUAL REPRODUCTION
1. Prefertilisation Events
3 stages: Pre-fertilization, Fertilization Post - fertilization events.
These are the events prior to the fusion of gametes
include gametogenesis andgamete transfer.�
It is the formation of male and female gametes
• : Similar gametes. They cannot
categorize into male female gametes. E.g. Some algae like Cladophora
The male and female gametes are distinct
types. Male gamete is called antherozoid (sperm) and
female gamete is called egg (ovum). E.g. Fucus(an alga), Human beings etc

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Human being 46 23
Housefly 12 6
Rat 42 21
Dog 78 39
Cat 38 19
Fruit fly 8 4
Ophioglossum 1260 630
Apple 34 17
Rice 24 12
Maize 20 10
Potato 48 24
Butterfly 380 190
Onion 32 16
Name of
organism
Chromos ome number
n meiocytes (2n) In gametes (n)
Sexuality (bisexual or unisexual) in organisms:
• Bisexual: Male female reproductive structures present
in the same individua
E.g.Hibiscus, Pisum
In flowering plants, male flower isstaminate (bears)
stamens) and female flower is pistillate (bears pistils)
If male female flowers are present on same plant, it is
called monoecious. E.g. Cucurbits coconuts.
E.g. Earthworms, sponge, tapeworm, etc.
Male and female reproductive structures are present on
different individuals.
male and female flowers are present on different plants, is called .
E.g. papaya date palm
E.g. Cockroach, higher animals etc. Fungi may be
(bisexual) or (unisexual)
Cell division during gamete formation:
- Many monerans, fungi, algae bryophytes have haploid
parental body. They produce haploid gametesby mitosis.
- Pteridophytes, gymnosperms, angiosperms animals
have diploid parental body. They produce haploid gametes
by meiosis of meiocytes (gamete mother cell).

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- Male gametes need a medium to move towards female
gametes for fertilization
- In most organisms, male gamete is motile and the female
gamete is stationary. In some fungi and algae, both types
of gametes are motile
In simple plants (algae, bryophytes pteridophytes), They
gamete transfer takes place through water medium. To
compensate the loss of male gametes during transport,
large number of male gametes is produced
- In seed plants, pollen grains (in anthers) carry male
gametes. They cannot gametes and ovule carries the egg. Pollen grains are
transferred to the stigma.
In bisexual self-fertilizing plants (e.g. peas), anthers
stigma are closely located. So transfer of is easy.
In cross pollinating plants (including dioecious plants),
helps in transfer of pollen grains. Pollen grains
germinate on the stigma and the pollen tubes carrying the
male gametes o Bisexual: Male female reproductive structures present
near the egg.
In dioecious animals, the fertilization helps for successful
transfer and coming together of gametes.
2. Fertilisation (syngamy)
- It is the fusion of gametes to form a diploid In rotifers, honeybees,
some lizards, birds (turkey) etc.,
female gamete develops to new organisms without leech, fertilization.
This is called
Types of fertilization
a. External fertilization: Syngamy occurs in the external If
medium (water), i.e. zygote is formed outside the body. it
most aquatic organisms (many algae, bony fishes etc.) and amphibians.
Such organisms show synchrony between the sexes and
release large number of gametes into the surrounding
medium to ensure syngamy.
The offspring are extremely vulnerable to
predators threatening their survival up to adulthood.
Syngamy occurs inside the body
of the organism. E.g. terrestrial organisms, belonging to

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fungi, animals (reptiles, birds, mammals) plants
(bryophytes, pteridophytes, gymnosperms angiosperms).
In this, non-motile egg is formed inside the female body
to where motile male gamete reaches and fuses.
In seed plants, the non-motile male gametes are carried to
female gamete by pollen tubes.
There is large number ofsperms produced but the number
of eggs is very low.
3. Postfertilisation Events
Zygote
- Development of the zygote depends on the type of life
cycle of the organism and the nature of environment.
- In fungi and algae, zygote develops a thick wall that is
resistant to desiccation and damage. It undergoes a period
of rest before germination.
- In organisms with haplontic life cycle, zygote divides by
meiosis into haploid spores that grow into haploid
individuals.
- Sexually reproducing organisms begin life as a zygote.
is the vital link between organisms of one
generation and thenext.
Embryogenesis
- It is the development of embryo from thezygote.
- During embryogenesis, zygote undergoes cell division (mitosis) and
cell differentiation.
- Cell divisions increase the number of cells in the embryo.
Cell differentiation causes the modifications of groups of
cells into various tissues and organs to form an organism.
Here, animals lay fertilized/unfertilized eggs.
E.g. In reptiles birds, the fertilized eggs covered by hard calcareous shell
are laid in a safe place. After incubation, young ones hatch out.
Here, the zygote develops into a young one inside the female
body. Later, the young ones are delivered out of the body. most of
mammals. Because of proper care and protection, the chances of
survivalof young ones are greater in viviparous animals.
Fertilization in Humans

VEGETATIVE
PROPAGATION
Vegative propagules
are able to give
rise to new plants.
Only in
Plants
Narrow, green and horizontal
branches develop from the base
of root.
Underground stems that store food
Eg:- Ginger.
Slender underground branches
develop from base of aerial shoot.
Eg:- Mint
Underground stem or root having
adventitious buds.
Eg. Potato
one internode long runner occurs
in some aquatic plants.
Eg. Pistia
RUNNER
RHIZOME
SUCKER
OFFSET
TUBER
FERTILIZATION
• Marked by the fusion of
male female gametes,
also called syngamy
• Can be of two types
• In terrestrial
animals birds
higher plants.
• Egg inside
the female
body fuses with
male gamete.
• In aquatic animals
amphibians
• Number of
gametes released
are more
• High risk of
predation.
INTERNAL EXTERNAL
in Amoeba Paramecium
in Plasmodium
in Yeast Hydra
Motile in Chlamydomonas,
Non – motile in penicillium
in Planeria, Flatworms
Leaf buds of Bryophyllum
Single cell divide
into two daughter cells
Single cell divide
into multiple daughter cells
By unequal division bud is
formed which forms new
offspring
Motile (zoospores) non –
motile (conidia) spores are
formed in Monera, protist,
algae and fungi.
Growth of fragmented
region into new organism
New plants are formed
from vegetative propagules
like buds, tuber etc.
Binary
Multiple
Budding
Fragmentation
VegetativePropagation
SporeFormation
Gemmule formation
in sponges (Budding)
Unfertilized egg
develops into an adult
Eg; Honey bees
Clone is morphologically genetically
similar organism (identical) formed
by asexual reproduction
Single parent is
involved
Parthenogenesi
Gamete Transfer
Male and female
gametes formation
Male gamete –
antherozoid or sperm
Female gamete–
egg or ovum
Gametogenesis
PRE - FERTILIZATION EVENTS
SEXUAL
Male
Gamete
Fusion
Zygote
New
Organism
Female
Gamete
+
Male gamete is mainly
motile and female
is stationary
Two parents of
opposite sexes
are involved
• In reptiles birds
fertilized eggs are laid
with hard calcareous
shell.
• Young ones hatch after
incubation
• In majority of mammals
zygote develops into
young one inside the
body of female.
• Young ones are
delivered after birth.
OVIPAROUS
VIVIPAROUS
Zygote- Product of fertilization
Embryogenesis- formation of embryo
from zygote.
Zygote Embryogenesis
POST - FERTILIZATION EVENTS
In plants, zygote develops
ino embryo, ovules into seed
and ovary into fruit
Two stages of
embryogenesis –
cell division
cell differentiation
REPRODUCTION IN
ORGANISMS
ASEXUAL
Life Span: Period from
birth to natural
death of an organism
Fertilization in Humans
Underground shoots which have one
or more buds.
BULB

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Reproduction In Organisms

LIFE SPAN
1. Life span can be defined as the period from birth to the natural death of an organism.
2. It can vary from as short as few days to as long as a number of years.
3. It will be a mis concept to say that smaller organisms have shorter life span and larger
organisms have longer life span.
4. Maximum Life Span is the maximum number of years survived or the greatest age
reached by any member of a species.
5. The average life span means, the average number of years survived or age reached by
members of a population.
6. Life expectancy, the number of years an individual can expect to live, is based on
average life spans.
7. The maximum life span of wild animals is very difficult to estimate because signs of
senility, or extreme old age are seldom seen in the wild.
8. Animals living under natural conditions rarely approach their maximum possible age
because of very high death rates due to infant mortality, diseases, predators, bad
weather, accidents or competition for food and shelter.
9. Limited life span means death of every individual
organism is inevitable i.e. all individual are mortal except
single celled organisms.
10. The limited life span, mortality of organisms, a variety
of plant and animal species are well maintained on earth
through the process -reproduction.
11. Reproduction ensures the continuity of the different
species.
 Approximate life span of some organisms are as follows:
S.No. Plant Life Span S.No. Animal Life Span
1.
2.
3.
4.
5.
6.
7.
Rise
Rose
Banana
Mango
Banyan
Peepal
Sequoia
3-4 months
5-7 years
25 years
200 years
200-300 years
2000-3000 years
3000-4000 years
1.
2.
3.
4.
5.
6.
7.
Butter fly
Fruit fly
Dog
Crocodile
Horse
Elephant
Tortoise
1-2 weeks
30 days
20-30 years
60 years
60 years
60-90 years
100-150 years
REPRODUCTION
 Reproduction is defined as a biological process in which an organism gives rise to young
ones (offspring) similar to itself.
 The offspring grow, mature and in turn produce new offspring. Thus, there is a cycle of
birth, growth and death.
 Reproduction enables the continuity of the species, generation after generation. You will
study later in Chapter (Principles of Inheritance and Variation) how genetic variation is
created and inherited during reproduction.
 There is a large diversity in the biological world and each organism has evolved its own
mechanism to multiply and produce offspring.

 Habitat and internal physiology of organism and several other factors are collectively
responsible for how it reproduces.
 There are two types of reproduction:
(1) Asexual reproduction
(i) Offspring is produced by a single parent with or without the involvement of gamete
formation.
(ii) Gametic fusion is absent.
(2) Sexual reproduction
(i) Offspring is produced by two parents (opposite sex) with the involvement of gamete
formation.
(ii) Gametic fusion is present (fertilization/syngamy).
ASEXUAL REPRODUCTION
 A single individual (parent) is capable of producing offsprings in asexual type of
reproduction. As a result, the offsprings produced are exact copies of each
other and their parents. Such morphologically and genetically similar individuals
are called clones.
 It is common among single-celled organisms, plants and animals with relatively
simple organization.
 It is also called somatogenic reproduction because propagules are formed from
somatic cells of the parent.
 It occurs by fission, budding, sporulation, fragmentation, regeneration and
vegetative reproduction.

(a) Binary Fission
 In this process, the parent organism divides into two halves, each half forming an
independent daughter organism.
 It means, the parent body as a whole form the reproductive unit and the parent
continues living as two daughter individuals.
 Therefore, the organisms that undergo binary fission are said to be immortal.
(ii) It occurs in Bacteria (Moneran), Amoeba and Paramecium (Protists).
 Depending upon the plane of division, binary fission is of the following types:
(i) Simple Binary Fission (Irregular Binary Fission): Division can occur through any
plane, e.g.; Amoeba.
Paramecium-
Binary fission

(ii) Longitudinal Binary Fission: The plane of fission passes along the longitudinal
axis of the organism, e.g., Euglena.
(iii) Transverse Binary Fission: The plane of this division runs along the transverse
axis of the individual, e.g., Bacteria, Paramecium, Diatoms.
(b) Budding
 In yeast, the division is unequal and a small bud (protuberance) is produced that remains
attached initially to the parent cell, later on the bud gets separated and mature into new
yeast (cells).
 Budding or sporulation is also shown by oidia of Rhizopus.
 Buds are also reported in hydra.
(c) Spores: Members of the kingdom fungi and simple plants
such as algae reproduce through special asexual
reproductive structure. The most commonly produced
structures are conidia and zoospores.

b
 Zoospores
(i) These are motile and flagellated spores produced inside the zoosporangia under
favourable conditions.
(ii) In Chlamydomonas(n), the protoplast of cell divides to form 8-16 zoospores. They
are pyramid shaped and anteriorly biflagellated, resembling the parent cell. The
parent cell wall breaks and the zoospores are liberated in water. They enlarge
and behave as adult individuals.
(iii) Zoospores are also produced in the asexual life cycle of Achlya, Saprolegnia,
Phytophthora and Ulothrix.
(iv) Zoospores of Cladophora glomerata are diploid.
 Conidia
(i) In Penicillium, these spores are produced at the
tips of special hyphal branches, called conidiophores.
(ii) There are two types of conidiophores:
a. Unbranched/monoverticillate
b. Branched/biverticillate
(iii) The branches of conidiophores are called rami
and branches of rami are called metulae. Each
metula bears 2-6 flask shaped structures called
sterigmata (phialides). Each sterigma produces a
chain of conidia.
(iv) Features of Conidia:
a. Pigmented
b. Uni or multinucleated
c. The conidia in the chain are arranged in basipetal manner.
(d) Vegetative Reproduction
(i) Vegetative reproduction does not involve meiosis and fusion of gametes,
therefore it is considered ' as a type of asexual reproduction.
(ii) New plants or individuals are produced from vegetative parts of plants and newly
formed individuals are genetically identical to the parent plant.
(iii) It is common method of reproduction in the flowering plants.
There are two types of vegetative reproduction.
I. Natural Methods of Vegetative Reproduction:
 These are methods of plant multiplication occurring naturally in which a somatic
part of the plant detaches from the body of the mother and develops into a new
independent plant under suitable environmental conditions.
 The detachable somatic part that functions in vegetative propagation is called
vegetative propagule.
 It carries one or more buds. Natural buds occur over the nodes of the stem.
When placed in contact with damp soil, the buds sprout, producing roots and new
plants.

 This potential is exploited by farmers, e.g., tubers of potato, rhizome of banana
and ginger, bulbs, runners, offsets, stolons, aerial stems etc.
 Some propagules carry adventitious buds, e.g., normal and storage roots, leaves.
It occurs by following means:

STEM
Underground stems
 Different types of underground stems like tuber, Germinating rhizome, bulb and
corm can take part in Young shoot vegetative propagation.
 A portion of underground stem bearing bud Roots forms a new plant.
(i) Tuber: It is terminal portion of underground stem branch which is swollen on
account of accumulation of food. e.g., Potato, Artichoke
Eye of Potato
(ii) Rhizome: It grows obliquely or horizontally under soil surface. It is well
branched and bears nodes, internodes, buds and scale leaves. e.g., Banana,
Turmeric, Aspidium, Adiantum, Ginger
(iii) Bulb: Stem is unbranched, highly reduced and disc shaped. The bud is surrounded
by many concentric scale leaves. Leaf bases of inner ones are fleshy and edible
and outer ones are dry known as tunic. e.g., Onion, Garlic, Narcissus
(iv) Corm: It grows vertically beneath the soil surface. It bears nodes, internodes, buds and
scale leaves. e.g., Colocasia, Gladiolus, Freesia., Crocus, Amorphophallus

Creeping stems:
(i) Runner: It is elongated, prostrate, sub-aerial branch with long internodes and roots at
nodes. e.g., Grasses
(ii) Offset: Short horizontal branch which is one internode long and produces a cluster of
leaves above and the cluster of roots below is called offset. e.g., Eichhornia (Water
hyacinth), Pistia.
Water hyacinth or 'terror of Bengal' was introduced in Bengal because of its beautiful flowers
and shape of leaves. However, it turned out to be highly invasive aquatic weed that not only
spread to all water bodies of Bengal but also throughout India. It drains oxygen from the
water, which leads to death of fishes and other animals. It is very difficult to get rid off them
since it can propagate vegetatively by offset at a phenomenal rate and spread all over the water
body in a short period of time.
(iii) Stolon: It is subterranean long lateral branch arising from base of stem. It first grows
obliquely upward and then bends down to the ground surface.
e.g., Strawberry, Vallisneria Leaflets
(iv) Sucker: It arises by axillary bud of underground part of stem. This lateral
branch creeps below the soil surface, grows obliquely upward and produces new
shoot.
e.g., Chrysanthemum, Pineapple, Banana

(4) Aerial shoots: Each segment of stem having at least one node can form a new
plant.
e.g., Sugarcane, Opuntia
(5) Leaves: Leaves of several plants having adventitious buds help in vegetative
reproduction. In Bryophyllum adventitious buds arise from the notches present
at margins of leaves.
e.g., Adiantum (walking fern), Begonia, Streptocarpus, Saintpaulia and Kalanchoe.
(6) Bulbils: These are fleshy buds which produce new plant. e.g., Agave, Oxalis,
Ananas, Dioscorea, Lily, Chlorophytum
(7) Turions : Fleshy buds in aquatic plants helping in perennation, e.g., Potamogeton,
Utricularia.
ROOTS
(i) Both tap roots and adventitious roots takes part in vegetative reproduction due
to the presence of bud, known as radicle bud.

(ii) Adventitious buds on root detaches and gives rise to new plant.
New plants developed from
Tap roots in
Dalbergia sisso (Sheesham),
Populus, Psidium, Myrraya and Albizzia
Adventitious roots in
Ipomoea batatas (Sweet potato),
Tapioca, Yam, Dahlia and Asparagus
 You must have heard about the scourge of the water bodies or about the ‘terror of
Bengal’.
 This is nothing but the aquatic plant ‘water hyacinth’ which is one of the most invasive
weeds found growing wherever there is standing water.
 It drains oxygen from the water, which leads to death of fishes.
 You may find it interesting to know that this plant was introduced in India because of its
beautiful flowers and shape of leaves.
 Since it can propagate vegetatively at a phenomenal rate and spread all over the water
body in a short period of time, it is very difficult to get rid off them.
 It is interesting to note that asexual reproduction is the common method of
reproduction in organisms that have a relatively simple organisation, like algae and fungi
and that they shift to sexual method of reproduction just before the onset of
adverse conditions.
 Find out how sexual reproduction enables these organisms to survive during unfavourable
conditions?
 Why is sexual reproduction favoured under such conditions?
 Asexual (vegetative) as well as sexual modes of reproduction are exhibited by the higher
plants. On the other hand, only sexual mode of reproduction is present in most of the
animals.
SEXUAL REPRODUCTION
 Sexual reproduction involves formation and fusion of gametes to form the zygote
which develops to form the new organism.
Characteristics
1. Two fusion gametes can be produced by same individual or different individuals.
So it can be both uniparental as well as biparental (mostly).
Concept Builder

2. Offsprings produced are not identical to parents or amongst themselves.
3. It involves meiosis and syngamy.
4. It is a slow, elaborate or complex process. So multiplication is not so rapid.
All organisms have to reach a certain stage of growth and maturity in their life
cycle before they reproduce sexually. For understanding this better lets study
the different phases in the life cycle of organism.
Table: Differences between Asexual and Sexual Reproduction
Asexual Reproduction Sexual Reproduction
1. New individuals are formed from a single parent. Commonly two parents are involved in the formation
of new individuals through sexual reproduction.
2. Asexual reproduction does not require the
production of sex organs.
Formation of sex organs is a pre-requisite for sexual
reproduction.
3. It does not involve meiosis. All divisions are
mitotic.
Sexual reproduction involves meiosis at one or the
other stage. In higher plants, it occurs at the time
of spore formation or sporogenesis.
4. Asexual reproduction does not involve fusion of
cells or gametes.
It involve fusion of gametes.
5. New individual develops from one cell or a part of
one parent.
New individual develops from zygote i.e., fusion
product of two gametes.
6. New individuals are genetically similar to the
parents.
Offspring or new individuals are genetically
different from either of the two parents.
7. It does not introduce variability. Hence, asexual
reproduction has no evolutionary importance.
It introduces variability and is, hence of evolutionary
importance.
Phases in Life Cycle
Three phases are there in the organism's life cycle.
1. Juvenile phase
2. Reproductive phase
3. Senescent phase
1. Juvenile phase/pre-reproductive phase
 During this phase organism will show growth so that it can attain certain maturity
to perform the sexual reproduction.
 This phase is known as vegetative phase in plants. It is of variable durations in
different organisms.
2. Reproductive phase
 Reproductive organs develop and mature during this phase. In the higher plants,
end of juvenile phase or onset of reproductive phase is easily marked.
 In the higher plants during this phase, there is formation of reproductive
structures i.e., flowers.
 The motto of this phase is to produce the offsprings which may be similar or

dissimilar to parental generation. This phase is also of variable durations in
different organisms.
 Based upon flowering and fruiting pattern there are two types of flowering
plants, i.e., monocarpic and polycarpic.
Monocarpic Plants:
 They are plants which flower only once in their life. After flowering, they
produce fruits and die. All annuals (e.g., Wheat, Rice, Marigold) and biennial
plants (e.g., Radish, Carrot, Henbane), are monocarpic.
 A few perennial plants are also monocarpic. Certain bamboo species (e.g., Bambusa
tulda, Meloeanna bambusoides) live vegetatively for 50-100 years, flower and
fruit abundantly and then die.
 Strobilanthus kunthiana (vern. Neelakurinji) flowers once in 12 years.
 The last time it flowered was September-October 2006. The flowering
converted large hilly tracts of Kerala, Karnataka and Tamil Nadu into blue
stretches that attracted a large number of tourists.
Polycarpic Plants:
 They are perennial plants which after reaching maturity, flower repeatedly at
intervals, e.g., Mango, Apple, Jackfruit, Grape vine, Orange.
 Very few perennial plants bear flowers throughout the year, e.g., China rose
(Shoe Flower). The period between two flowering phases is called Inter flowering
period which is used for building up resources and is, therefore, a recovery
phase. It is not the juvenile phase but is part of the mature phase.
3. Senescent Phase:
 It is a post-reproductive phase. It involves structural and functional
deterioration of body by accumulation of waste metabolites which ultimately
leads to death.
 In both plants and animals, hormones are responsible for the transitions between
three phases. Interaction between hormones and certain environmental factors
regulate the reproductive processes and the associated behavioural expressions
of organisms.
 The females of placental mammals exhibit cyclical changes in the activities of ovaries and
accessory ducts as well as hormones during the reproductive phase.
 In non-primate mammals like cows, sheep, rats, deers, dogs, tiger, etc., such cyclical changes
during reproduction are called oestrus cycle.
 Where as in primates (monkeys, apes, and humans) it is called menstrual cycle.
 Many mammals, especially those living in natural, wild conditions exhibit such cycles only during
favourable seasons in their reproductive phase and are therefore called seasonal breeders.
 Many other mammals are reproductively active throughout their reproductive phase and hence
are called continuous breeders.
EVENTS IN SEXUAL REPRODUCTION
 After attainment of maturity, all sexually reproducing organisms exhibit events and
processes that have remarkable fundamental similarity, even though the structures
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associated with sexual reproduction are indeed very different.
 These sequential events may be grouped into three distinct stages, namely, the pre-
fertilisation, fertilisation and the post-fertilisation events.
1. Pre-fertilization events
These are events in sexual reproduction which occur prior to the process of fertilization.
The two main prefertilization events are gametogenesis and gamete transfer.
(a) Gametogenesis: It refers to the process of formation of gametes-male and female.
Categories of Gametes:
(i) Isogametes: When the fusing gametes are morphologically similar they are known as
isogametes or homogametes.
e.g., (i) Algae: Chlamydomonas debaryana, Ulothrix
(ii) Fungi : Synehytrium, Rhizopus
(ii) Heterogametes: When the fusing gametes are
morphologically distinct types, they are known as
heterogametes. It is the feature of majority of
sexually reproducing organisms.
e.g., (i) Algae: Volvox, Chara, Fucus
(ii) All Bryophytes, Pteridophytes,
Gymnosperms and Angiosperms.
In such organisms, male gamete is called
antherozoid or sperm and the female gamete is
called egg or ovum.
Sexuality in organisms:
 Sexual reproduction in organisms generally involves the fusion of gametes from two
different individuals. But this is not always true.
 Plants may have both male and female reproductive structures in the same plant
(bisexual) or on different plants (unisexual).
 In several fungi and plants, terms such as homothallic and monoecious are used to denote
the bisexual condition and heterothallic and dioecious are the terms used to describe
unisexual condition.
A. Sexuality in animals
 The individuals of all species either male or female (unisexual)?
 Or are there species which possess both the reproductive organs (bisexual)?
 You probably can make a list of several unisexual animal species.
 Earthworms, sponge, tapeworm and leech, typical examples of bisexual animals that
possess both male and female reproductive organs, are hermaphrodites.
 Cockroach is an example of a unisexual species.

Name of organism Chromosome number in
meiocyte (2n)
Chromosome number in
gameter (n)
Fruit fly 8 4
House fly 12 6
Garden pea 14 7
Maize 20 10
Rice 24 12
Apple 34 17
Cat 42 21
Human beings 46 23
Potato 48 24
Dog 78 39
Sugarcane 80 40
Poa litorosa (grass) 266 133
Butterly 380 190
Ophioglossum (Adder's tongue fern) 1260 630
B. Sexuality in Plants
 In most of the lower sexually reproducing organisms, two fusing gametes are
morphologically similar.
 If these gametes belong to the same parent then such organisms are called

homothallic, e.g., fungi (Mucor mucedo). When these gametes belong to different
parents then these organisms are called heterothallic.
Higher Organisms:
 In higher plants there is well developed sex
organs and there is clear distinction between
male and female sex organs.
 Angiosperms possess flowers as reproductive
structures. The male sex organ is called stamen
and female sex organ is carpel or pistil.
 If male and female sex organs occur in the same
flower then these plants are called bisexual, e.g.,
China rose. If flowers possess only stamen or
carpel then these plants are called unisexual.
 When male flower (staminate) and female flower (pistillate) are present on same
plant body such plants are monoecious, e.g., Acalypha, cucurbits, coconut and
maize.
 However, if they are present on separate plant body then these plants are known
as dioecious, e.g., date palm, papaya and
mulberry.
 In some of the lower plants also the monoecious
and dioecious condition occur. For knowing this,
we will study the sexuality in Chara and
Marchantia.
Sexual Reproduction in Chara and Marchantia :
 The Chara is a green alga. It is oogamous. The sex organs are highly specialised.
Some workers prefer to call the male sex organ as antheridium and female as
oogonium, while others did not favour this terminology.
 They call the male sex organ as globule and the female as nucule and this
terminology is largely followed in Chara. These sex organs are exceptionally
multicelled and covered by jacket.
 The jacket of nucule is formed by tube cells and the jacket of globule is formed
by shield cells. The nucule has a cap of 5 coronary cells.

 The sex organs are borne on the adaxial surface of the short lateral branch
almost on each node. The nucule occupies an upper position than the globule.
 While most of the species of Chara are monoecious, C. wallichii is dioecious. The
globule matures prior to nucule (protandrous condition).
 Each antheridium produces many band shaped, spirally coiled, biflagellate
antherozoids. The oogonium contains a single egg. The egg is laden with starch
and oil globules.
 In Marchantia, the archegonia are borne on special branches called
archegoniophores or the female receptacles. The archegonia may be stalked or
sessile.
Cell division during gamete formation
 Gametes are haploid though the parent plant body producing these gametes may
be either haploid or diploid.
 A haploid parent produces the gametes by mitotic division however organisms
having diploid body the gametes are formed through reductional division, i.e.,
meiosis.
 In these organisms specialised cells called meiocytes or gamete mother cells
undergo meiosis. At the end of meiosis only one set of chromosomes gets
incorporated into each gamete.
(b) Gamete transfer:
 After the formation of male and female gametes, compatible gametes must be
physically brought together to facilitate fusion (fertilisation or syngamy).
 In few fungi and algae, both types of gametes are motile. In heterogametic
condition, the female gamete is non motile. So there is a need of a medium
through which the male gametes move.
 Water is the medium for gamete transfer in algae, bryophytes and
pteridophytes. A large number of the male gametes however, fail to reach the
female gametes.
 To compensate this loss of gametes, the number of male gametes produced in
several thousand times the number of female gametes produced.
 In seed plants, pollen grains are the carrier of male gametes and ovule has the
egg.

2. FERTILISATION
 The most vital event of sexual reproduction is the fusion of gametes. This
process is called syngamy or fertilisation which results in the formation of a
diploid zygote.
 Syngamy can occur in external medium as well as inside the body of organism.
 On this basis syngamy can be distinguished into two types :
(a) External fertilisation :
 Syngamy occurs outside the body of organism in external medium (water). It is
shown by majority of aquatic organisms like most of algae, fishes as well as
amphibians.
 Organisms exhibiting external fertilisation show great synchrony between the
sexes and release a large number of gametes into the surrounding medium in
order to enhance the chances of syngamy.
 The disadvantage associated with it is that the offsprings are extremely
vulnerable to predators.
(b) Internal fertilisation:
 Syngamy occurs Inside the body of
organisms. It is present in majority of
plants like bryophytes, pteridophytes,
gymnosperms and angiosperms.
 It occurs in few algae like Spirogyra. In all
these organisms egg is formed inside the
female body where syngamy occurs.
 The male gamete is motile and has to reach the egg in order to fuse it. In order
to enhance the chances of syngamy large number of sperms are produced in these
organisms and to compensate for this there is significant reduction in number of
eggs produced.
Sexual reproduction is divided into two types.
Zooidiogamy :
It is a type of sexual reproduction in which transfer of male gamete occurs through the
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medium i.e., water. It occurs in several simple plants like algae, bryophytes and
pteridophytes.
Siphonogamy:
It is a type of sexual reproduction in which male gamete carrier is pollen grain and
transfer of male gamete occurs through pollen tube. It is the feature of seeded plants
like gymnosperms and angiosperms. Pollen grains are produced in anthers, therefore have
to be transferred to the stigma before it can lead to fertilisation.
External and internal fertilisation should not be confused with exogamy and
endogamy.
Exogamy: Two fusing gametes belong to different individuals. Also known as cross
fertilisation.
Endogamy: Two fusing gametes belong to same individual. Also known as self-
fertilisation.
3. POST-FERTILISATION EVENTS
Events in sexual reproduction after the formation of zygote are called post-
fertilization events.
Zygote:
 It is the first cell of the new generation in all sexually reproducing organisms.
Zygote is always diploid.
 It is formed in the external aquatic medium in those organisms which perform
external fertilization. Zygote is produced inside the body in cases where
fertilization is internal.
 Zygote is a vital link between two successive generations. It ensures the
continuity of race from generation to generation.
 The body of all multicellular organisms develops from the single-celled zygote. All
the cells of the body, therefore, contain the same genetic traits as present in
the zygote.

Embryogenesis
A. In Plants:
 Embryogenesis is the process of development of embryo from zygote. Embryo is
a multicellular stage in the life cycle of a plant or animal prior to formation of an
independent individual.
 In embryogenesis, the zygote undergoes repeated cell divisions through mitosis.
The divisions help in growth of the embryo.
 Cells undergo differentiation attaining specific shape, size and function. Cell
differentiation occurs at specific locations resulting in production of different
tissues, organs and organ systems.
 Development of different external and internal structures is called
morphogenesis. In flowering plants, zygote develops into embryo.
 The food for development of embryo comes from a special tissue known as
endosperm. Ultimately, the fertilized ovule matures into a seed.
 A number of seeds develop in an ovary depending upon the number of ovules.
Meanwhile, wall of the ovary also proliferates. It produces pericarp. The pericarp
can be dry or fleshy.
 The ripened ovary with pericarp and seeds is called fruit. As the fruit begins to
develop, sepals, petals, stamens, style and stigma normally sheds. After dispersal,
the seeds, upon reaching suitable substratum germinate and form new plants.
B. In Animals:
 Animals are categorised into oviparous and viviparous based on whether the
development of the zygote take place outside the body of the female parent or
inside.
 Whether they lay fertilised/unfertilised eggs or give birth to young ones.
 In oviparous animals like reptiles and birds, the fertilised eggs covered by hard

calcareous shell are laid in a safe place in the environment; after a period of
incubation young ones hatch out.
 On the other hand, in viviparous animals (majority of mammals including human
beings), the zygote develops into a young one inside the body of the female
organism.
 After attaining a certain stage of growth, the young ones are delivered out of
the body of the female organism.
 Because of proper embryonic care and protection, the chances of survival of
young ones is greater in viviparous organisms.
II. Artificial Methods of Vegetative Reproduction:
 Artificial methods are man-made special techniques in which, part of somatic body of a
plant is made to develop into new independent plant.
 Artificial methods are used to propagate desired varieties according to human
requirements, Rainy and spring seasons are the best periods for vegetative propagation.
 The various horticultural methods of vegetative propagation are as follows:
1. Cuttings:
 Cuttings are cut pieces of stem, leaves and root which are planted in nurseries in natural
polarised fashion, Pre-requisite to successful cutting is induction of rooting, For this,
root promoting chemicals like IBA, NAA are used,
(i) Stem Cuttings :
It is a common artificial method of plant propagation, 20-30 cm long pieces of one year
old stems are cut and their lower ends are dipped in dilute auxin for several minutes
before planting in the soil. The lower ends develop adventitious roots, Buds present over
the exposed parts sprout and form the shoot system,
e,g., Rosa, Duranta, Citrus, Clerodendron, Thea, Bougainvillea, Croton and China rose
(ii) Leaf Cuttings: Snake plant (Sansevieria) can be propagated by leaf cuttings, Leaves are
cut transversely into two or three parts and planted in vertical position in the soil. For
successful leaf cutting, besides induction of rooting, formation of adventitious buds is
also important.
(iii) Root Cuttings : They are long pieces of roots which are used to artificially propagate
new plants, Ability to form adventitious roots and adventitious buds are pre-
requisites. Root cuttings are used in propagation of Lemon, Tamarind, Blackberry and
Raspberry.
2. Layering:
(i) It is a type of rooting-cutting method in which adventitious roots are induced to develop
on a soft stem while it is still attached to the plant.
(ii) It is carried out on one year old basal shoot branches commonly during early spring or
early rainy season.

(iii) A soft basal branch is defoliated in the middle where a small injury or cut is also given,
like tongueing (oblique cut), notching (V-shaped cut), ringing (removal of a ring of bark).
The injured defoliated part is pegged in the soil to develop adventitious roots. The
pegged down branch of the plant is called layer. Later on as the roots develop, the layer
is separated and planted.
(iv) Layering is of following types:
(a) Tip Layering : A shoot is bent down in the soil in such a way that its basal end is slanting
while the tip is upright. Soil is pressed. It induces root formation and later growth of
shoot tip.
e.g., Blackberry, Raspberry.
(b) Trench Layering : The basal branch is pegged in a horizontal position in a trench made
in soil. It develops a number of vertical shoots. e.g., Walnut, Mulberry.
(c) Serpentine Layering : The basal branch is pegged at several places in soil at regular
intervals, so as to form many plants. e.g., Clematis
(d) Mound (Stool) Layering
The shoot is pruned and its lower part is covered by soil but the tip is kept outside the
soil. When a number of new shoots develop, soil and saw dust are poured over the base to
form a mound. Each shoot develops roots. Rooted shoots are separated and planted.
e.g., Currant, Gooseberry, Apple, Pear and Jasmine
(e) Gootee (Air Layering)
(i) It is an ancient horticultural technique for propagation of tropical and subtropical trees

and shrubs where soft branches do not occur near the soil.
(ii) During early monsoon rains, 3-5 cm long ring of bark is removed from the basal region of
a healthy and woody branch. It is covered by a thick plaster of grafting clay. Grafting
clay is made of 1 part cow dung, 1 part finely cut hay or moss and two parts clay.
To it is added water and a small quantity of root promoting hormones like IAA, IBA or
NAA. It is then wrapped in polythene. After 2-3 months, roots appear. The shoot is now
cut below the covered part and used for planting.
e.g., Litchi, Pomegranate.
3. Grafting:
(i) Grafting is a technique of connecting two parts, usually a root system and a shoot system
of two different plants in such a way that they unite and later develop as a composite
plant.
(ii) It is used only in cambium containing eustelic plants.
(iii) A small shoot of plant with superior traits is employed. It is called graft or scion. It
should have one to several buds. The root system of the other plant is allowed to remain
intact. It is called stock (under stock). The shoot of the stock is often cut 10-30 cm
above the base of the root. Leaves and buds present over the stump of stock are
removed.
(iv) In grafting, scion is fixed over the stock in a manner that cambia of the two come in
contact. The union is covered with grafting wax. It is then tied with the help of a
bandage, tape, rubber or nail. The buds of the stock are not allowed to sprout.
They are removed as soon as they are noticed.
e.g., Mango, Apple, Pear, Citrus, Guava, Plum, Peach, Pine etc.
 The various types of grafting are as follows:
(a) Tongue (Slice or Whip) Grafting
Oblique sloping cut or notch is given to both stock and scion. The two perfectly fit upon
one another. They are tied together.

(b) Wedge Grafting
V-shaped notch is given to stock while wedge like cut is given to scion.
(c) Crown Grafting
Many scions are selected and shaped at the base to form wedge. Many slits are formed on the
sides of stock. Scions are inserted in the slits and are bandaged.
(d) Approach Grafting
Two independently growing plants are brought together. The shoots of the two are given cuts at
the same level for a distance of 2.5 -5.0 cm. The cuts are in the form of smooth slices of bark,
tongue shaped cuts or deeper vertical cuts. In this grafting, the scion is cut below the graft
while stock is cut above the graft after the establishment of union.
(e) Bud Grafting
Scion is a bud with a small piece of bark and cambium. Stock is given a T-shaped cut. Bark is
lifted to expose cambium. Bud is inserted and the bark is allowed to come back to its original
position. Only the bud is exposed. The joint is treated with grafting wax and bandaged. Bud
sprouts after 3-5 weeks. Bud grafting is commonly practised in apple, peach and rose.

4. Micropropagation:
 Micropropagation is the raising of new plants from a small plant tissue with the help of
tissue culture technique.
 Tissue culture is the technique of maintaining and growing cells, tissues, etc. and their
differentiation on artificial medium under aseptic conditions inside suitable containers.
 N.Grew first pointed out that flowers are reproductive organs of plants.
 Largest male gamete is seen in Cycas.
 Citric acid helps in attraction of male gametes towards the archegonium in Lycopodium, a
pteridophyte.
 Parthenospores: A spore is formed directly from a gamete. It is also called azygospore.
 Parthenogamy : It is the union of two incompatible gametes like two female gametes.
 Parthenoapogamy: It is the fusion of vegetative nuclei.
 Parthenocarpy (Noll, 1902) : It is formation of fruits without fertilization. It is
useless in case of plants where seeds provide the economic produce, e.g., Almond ,
Walnut, Coconut, Pomegranate.
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SUMMARY
1. Reproduction enables a species to live generation after generation.
2. Asexual reproduction is common in simple organisms like fungi, algae and some
invertebrates.
3. Offsprings formed in asexual reproduction are identical and are called clones.
4. The most common asexual structures are zoospores in algae and conidia in fungi.
Prokaryotes and unicellular organisms reproduce asexually by binary fission or
cell division. Asexual reproduction in angiosperms occurs by vegetative
propagation i.e., runners, rhizomes, suckers, tubers, offsets.
5. Sexual reproduction is slow and complex process, involving formation and fusion
of gametes. Events are categorised as pre-fertilisation (involving gametogenesis
and gamete transfer), fertilisation and post-fertilization (zygote formation and
embryogenesis).
6. Plants may be monoecious or dioecious. Flowers may be unisexual or bisexual.
7. Gametes are haploid and can be produced by meiosis or mitosis.
8. In seeded plants, pollen grains are the carriers of male gametes.
9. Fertilisation (syngamy) can be internal or external forming a specialised cell
called zygote, which forms embryo by embryogenesis.
10. In flowering plants, ovary develops into fruit and ovules into seeds after
fertilisation. Embryo in mature seed is the progenitor of next generation.
11. Organisms do not survive for indefinite period of time. They have a definite life-
span which varies from few hours to several thousand years.
Death is an important event of the life-cycle of all organisms.
12. Reproduction is characteristic of all living organisms. It is the process by which
an organisms produces more individuals of the same kind.
(i) If a species is to survive, it must produce new individuals.
(ii) Reproduction is of two types -asexual and sexual.
(iii) Production of large number of individuals by a single parent is called asexual
reproduction. It does not involve. the fusion ·of gametes and the offsprings have
a genetic composition exactly identical to the parents.
(iv) Sexual reproduction involves fusion of gametes and the offsprings are genetically
different.
13. Asexual reproduction may take place by fission (e.g., Amoeba, bacteria), budding
(e.g., yeast), fragmentation (e.g., filamentous algae) and spores (e.g., Mucor,
Aspergillus, Chlamydomonas).
(i) Vegetative parts of the plant such as bulbs, runners, rhizome, corm, tuber,
offsets, roots and leave also help in the multiplication of plants.
(ii) Some artificial methods, such as cutting, layering and grafting are used to exploit
commercial application of vegetative multiplication.
(iii) One of the biggest disadvantage of asexual reproduction is that it does not
produce genetic variations which is very essential for the evolution of a species.

EXERCISE – 1
Section – A
Q.1 Which of the following is not an artificial method of vegetative reproduction?
(1) Cutting (2) Grafting (3) Layering (4) Bulbils
Q.2 The plant propagated through roots is :
(1) Sweet potato (2) Asparagus (3) Dahlia (4) All of these
Q.3 In grafting, scion belongs to :
(1) Plant having superior or desirable characters
(2) Plant having well developed root system
(3) Plant resistant to diseases
(4) Both (2) (3)
Q.4 Gootee (air layering) is commonly used in :
(1) Bryophyllum (2) Lemon (3) Eichhornia (4) Tapioca
Q.5 Stem cutting are commonly used in propagation of :
(1) Mango (2) Cotton (3) Rose (4) Banana
Q.6 Ginger is multiplied vegetatively by means of
(1) Bud (2) Tuber (3) Corm (4) Rhizome
Q.7 A piece of plant part which is used in tissue culture is called as
(1) Explant (2) Inoculant (3) Somaclone (4) Clone
Q.8 Secondary nucleus present in the middle of embryo sac is
(1) Tetraploid (2) Triploid (3) Diploid (4) Haploid
Q.9 In angiosperms, syngamy is required for the formation of
(1) Endosperm (2) Embryo (3) Fruit wall (4) Suspensor
Q.10 A piece of potato tuber will form a new plant if it possesses
(1) Roots (2) Eyes (3) Stored food (4) Branches
Q.11 Layering is used in vegetative propagation of
(1) Jasmine (2) Rose (3) Mango (4) All of these
Q.12 Which is not involved in embryogenesis?
(1) Cell multiplication (2) Cell differentiation
(3) Equational division (4) Reduction division
Q.13 A method in which roots are induced on the stem/ branch , while it is still
attached to the parent plant is called
(1) Cutting (2) Grafting (3) Layering (4) Vivipary
Q.14 If a plant fails to develop viable seeds, it could best be grown by
(1) Cutting (2) Grafting (3) Layering (4) Micropopagation
Q.15 The study of formation, growth and development of a new individual from an egg
is known as
(1) Cytology (2) Embryology (3) Histology (4) Genetics
Q.16 A leaf cell of a flowering plant has 22 chromosomes, then the number of
chromosome would be
(1) 11 in gametes (2) 22 in gametes (3) 44 in embryo (4) 11 in a cell of stem
Q.17 The tegmen of the seed develops from
(1) Perisperm (2) Funicle (3) Inner integument (4) Outer

integument
Q.18 In angiosperm, the female gametophyte is represented by the
(1) Egg apparatus (2) Embryo (3) Synergids (4) Embryo sac
Q.19 The nuclei of the sperm and egg fuse as a result of
(1) Base pair relation of DNA and RNA
(2) Formation of hydrogen bonds
(3) Mutual attraction caused by differences in electrical charges
(4) Attraction of protoplasts of the egg and the sperm
Q.20 Parthenogenesis is defined as the development of an organism directly from
(1) Egg without fertilization (2) Synergids without fertilization
(3) Fruits without fertilization (4) Fruit without pollination
Q.21 How many meiotic divisions are necessary for the formation of 100 grains of
wheat?
(1) 100 (2) 125 (3) 25 (4) 50
Q.22 The most significant value of vegetative propagation is that
(1) It enables rapid production of genetic variation
(2) It is a means of producing a large population of individuals, genetically
identical to the
parent
(3) It ensures that the progeny remain safe from attack of diseases and pests
(4) It is an ancient practice
Q.23 The zygospore of Volvox gives rise to
(1) Zoospore (2) Aplanospore (3) Hypnospore (4) Parthenospore
Q.24 The antherozoids of Volvox are
(1) Non-motile (2) Uniflagellate (3) Biflagellate (4) Multiflagellate
Q.25 Find odd one (w.r.t. sexuality)
(1) Cannabis (2) Cycas (3) Coconut (4) Date palm
Q.26 In Marchantia the meiosis is
(1) Zygotic (2) Gametic (3) Both (1) (2) (4) Sporic
Q.27 The star shaped bodies meant for vegetative reproduction of Chara are rich in
(1) Starch (2) Lipids (3) Proteins (4) Mannitol
Q.28 The nucule of Chara is capped by
(1) Nodal cells (2) Internodal cells (3) Tube cells (4)
Coronary cells
Q.29 The asexual reproduction in Saccharomyces occurs by means of
(1) Oidia (2) Conidia (3) Chlamydospores (4) Budding
Q.30 The conidia of Penicillium are
(1) Thick walled, uninucleate (2) Thin walled, uni or multinucleate
(3) Thick walled, multinucleate (4) Thin or thick walled, multinucleate
Q.31 The sequence of structures in a penicillus of Penicillium digitatum shall be
(1) Conidiophore → Rami → Phialides → Metulae → Conidia

(2) Conidiophore → Rami → Matulae → Phialides → Conidia
(3) Ramus → Conidiophore → Metulae → Phialides → Conidia
(4) Metulae → Rami → Conidiophore → Phialides → Conidia
Q.32 The ascocarp of the Penicillium is usually a
(1) Perithecium (2) Apothecium (3) Cleistothecium (4) Ascostroma
Q.33 In bryophytes, the diploid number of chromosomes occurs in the
(1) Gametes (2) Spores
(3) Nuclei of gametophyte (4) Spore mother cells
Q.34 Gametophytic generation is dominant in
(1) Pteridophytes (2) Gymnosperms (3) Angiosperms (4) Bryophytes
Q.35 Potato multiplies vegetatively by
(1) Rhizoids (2) Tubers
(3) Adventitious branches (4) Gemmae
Q.36 The number of thalli formed by a gemma of Marchantia upon successful
germination is/are
(1) One only (2) Two only (3) Four only (4) Several
Q.37 Which of the following is not applicable to asexual reproduction in organisms?
(1) It is always monoparental
(2) It is a quick method of multiplication
(3) Gamete formation may take place
(4) It is common among single celled organisms only
Q.38 Which of the following marks the end of juvenile phase in higher plants?
(1) Appearance of flowers (2) Appearance of vegetative bud
(3) Formation of cataphylls (4) Formation of stipule
Q.39 Which of the following plants is monocarpic?
(1) Mangifera (2) Acacia (3) Bambusa (4) Zizyphus
Q.40 Which is not true for life span of an organism?
(1) Period from birth to natural death of an organism
(2) It is necessarily correlated with size of organisms
(3) It may be very short
(4) Senescence is a phase of life span
Q.41 Which is not essential for sexual reproduction in organisms?
(1) Gametogenesis (2) Syngamy
(3) Dioecism (4) Alternation of generation
Q.42 Spermatophytes do not need water for fertilization because they have/exhibit
(1) Flowers (2) Ovules (3) Siphonogamy (4) Zooidogamy
Q.43 Select correct match
(1) Bulbils : Garlic (2) Suckers : Chrysanthemum
(3) Corms : Aspidium (4) Bulb : Artichoke
Q.44 Which of the following is the vital link that ensures continuity of species
between organisms of one generation and the next?
(1) Male gamete (2) Female gamete (3) Zygote (4) Embryo
Q.45 Match the following organisms w.r.t. chromosome number in meiocytes :

a. Maize (i) 12
b. House fly (ii) 34
c. Apple (iii) 78
d. Dog (iv) 20
(v) 8
(1) a(iv), b(i), c(ii), d(iii) (2) a(i), b(ii), c(v), d(iv)
(3) a(ii), b(i), c(iii), d(v) (4) a(v), b(ii), c(iv), d(iii)
Q.46 Which of the following statement is not true?
(1) Life span is the period from birth to the natural death of an organism
(2) All smaller organisms have very short life span
(3) Life expectancy is the characteristic of populations
(4) Maximum life span is the characteristic of species
Q.47 Which of the following pair of animals are having almost similar maximum life
span?
(1) Ant queen and squirrel (2) Toad and house mouse
(3) Bull frog and house rat (4) Carp and guinea-pig
Q.48 Which one can't be included under basic feature of reproduction?
(1) DNA replication
(2) Formation of reproductive units
(3) Meiosis is never involved as all divisions are mitotic
(4) Growth due to synthesis of more protoplasm
Q.49 Which of the following can show somatogenic reproduction?
(1) Paramecium (2) Amoeba (3) Hydra (4) All of these
Q.50 Which of the following plays an important role in controlling reproduction?
a. Day length b. Nervous system c. Endocrine system
(1) c only (2) b only (3) b and c only (4) a, b and c
Q.51 In mammals the sheep, cow, rat etc. show reproduction during
(1) Oestrus phase (3) Menstrual phase (2) Anoestrous phase
(4) Diapause phase
Q.52 Which of the following animal is bisexual?
(1) Ants (2) Cockroach (3) Leech (4) Wasps
Q.53 Which of the following statement is not correct w.r.t. earthworm?
(1) One pair of testis in segment 9 (2) One pair of ovary in segment 13
(3) Protandrous condition (4) Cross-fertilization
Q.54 Which of the following pheromone is involved in sexual reproduction in silk moth?
(1) Civetone (2) Bombykol (3) Ecdyson (4) Villikinin
Q.55 Which of the following is the largest animal?
(1) Whale (2) Giant tortoise (3) Hippopotamus (4) Elephant
Q.56 The fusion of male and female gametes in course of fertilization is called
(1) Syngamy (2) Hologamy (3) Isogamy (4) Merogamy
Q.57 Among butterfly, pigeon, horse and goat, which one has the highest chromosome
number in gametes?
(1) Buttertly (2) Pigeon (3) Horse (4) Goat

Q.58 Which of the following members show the same number of chromosomes in their
gamets?
(1) Honeybee and Hydra (2) Cockroach and mosquito
(3) Monkey and frog (4) Housefly and
fruitfly
Q.59 Eggs are covered with a tough, leathery coat in case of
(1) Sharks (2) Bony fishes (3) Lizard (4) Urochordates
Q.60 External syngamy occurs in case of
(1) Reptiles (2) Birds (3) Mammals (4) Bony fishes
Section – B
Q.1 In the process of asexual reproduction
(1) Large number of individuals are produced due to involvement of reduction
division
(2) Individuals are genetically similar to one another but not to their parent
(3) There is no need to search for a mate
(4) Consumption of resources is very high
Q.2 A portion of underground stem bearing bud forms a new plant in
(1) Adiantum, Colocasia and Vallisneria (2) Narcissus, Gladiolus and Freesia
(3) Garlic, Onion and Water hyacinth (4) Turmeric, Ginger and Strawberry
Q.3 Which of the following statement about vegetative reproduction is incorrect?
(1) Stem cutting is a common horticultural method of plant propagation
(2) In trench layering, the basal branch is pegged at several places in soil at
regular intervals
(3) Stock has large diameter than scion in crown grafting
(4) Gootee is an ancient method of propagation in subtropical trees and shrubs
Q.4 Grafting method can be used
(1) In all tracheophytes (2) Only in gymnospermic plants
(3) In cambium containing eustelic plants (4) Only in atactostelic
plants
Q.5 Select the method(s) of reproduction which can preserve good qualities of a
variety in dwarf Rhododendron
(1) Gootee, heterogamy (2) Droplayering
(3) Oogamy (4) Root cutting, anisogamy
Q.6 Examine the figures A, S, C D given below and select the right option for
female sex organs.
(1) a, d f (2) b, d f (3) a, c e (4) a, d e

Q.7 Which of the following organisms show great synchrony between sexes and
release a large number of gametes into the surrounding medium to enhance the
chances of fertilisation?
(1) All terrestrial plants (2) Majority of fungi and few algae
(3) Majority of algae (4) All spermatophytes
Q.8 Select the incorrect statement
(1) Citric acid helps in zooidogamy in Sphagnum
(2) Flowers are bisexual in sweet potato
(3) External fertilisation is found in Ulothrix
(4) The nucule in Chara has a cap of five coronary cells
Q.9 Which of the following plants produce non-motile male gametes?
(1) Ulothrix, Marchantia (2) Strobilanthus, Chara
(3) Spirogyra, Ulothrix (4) Mangifera, Pinus
Q.10 The vital link that ensures continuity of species between organisms of one
generation and next are all, except
(1) Zygospore (2) Oospore (3) Zygote (4) Oosphere
Q.11 Which is not an example of bisexual (hermaphrodite) animal?
(1) Earthworm (2) Sponge
(3) Tapeworm and leech (4) Cockroach
Q.12 In flowering plants, after fertilisation the :
(1) Sepals, petals and Stamens fall off
(2) Ovules develop into the seed
(3) Ovary develops into the fruit which develops a thick protective wall called
pericarp
(4) All of these are correct
Q.13 Select an incorrect statement for asexual reproduction :
(1) Offspring likely to be genetically identical
(2) Offspring are clones
(3) Vegetative reproduction is not a type of asexual reproduction
(4) Asexual reproduction is common among single-celled organisms
Q.14 Which of the following statement is incorrect?
(1) Neelakuranji flowers once in 12 years (2) Mango and Silence
plants are trioecious
(3) Marchantia is dioecious (4) Cucumber bears unisexual flowers
Q.15 Which of the following is incorrectly matched?
(1) Internal fertilisation – Embryophyte (2) Bulbils – Common in
aquatic plants
(3) Grafting – Apple (4) Chara wallichi –
Dioecious
Q.16 Which of the following is incorrectly matched :
(1) Globule – Male sex organ of Chara
(2) Penicillium – Metulae

(3) Acalypha – Dioecious plant
(4) Spermatophytes – Internal fertilisation
Q.17 Mark the incorrect statement :
(1) Gootee formation and grafting are artificial means of vegetative propagation
for plants like litchi and mango respectively.
(2) Largest male gamete is seen in Cycas
(3) Sex organs archegonia and antheridia are produced on gametophyte in case of
bryophytes and no sporophyte in case of pteridophytes.
(4) In angiosperms oogamous sexual reproduction occurs.
Q.18 Choose correct statement regarding budding in yeast :
(1) The cytoplasmic division is equal and a small bud is produced.
(2) The cytoplasmic division is unequal and a small bud is produced.
(3) Buds remain joined with parent cell.
(4) Meiosis takes place during budding.
Q.19 Choose correct match :
(1) Archegoniophore – Male sex organ (2) Antheridiophore – Female sex organ
(3) Stigma – Pollen production (4) Ovary – Fruit
Q.20 It is essential that meiosis has to occur if :
(1) The diploid organism has to produce diploid gametes
(2) The diploid organism has to produce haploid gametes
(3) The haploid organism has to produce haploid gametes
(4) The haploid organism has to produce diploid gametes
Q.21 Find correct statement w.r.t. adventive polyembryony :
(1) Megaspore mother cell in ovule produces a embryo sac directly
(2) A cell of nucellus or integument directly produces a somatic embryo
(3) Many embryo arises from one embryo sac
(4) A cell of nucellus gives rise to a embryo sac
Q.22 In serpentine layering :
(1) A part of lower branch is cut and is pegged down.
(2) Adventitious roots are induced on an aerial shoot after ringing.
(3) Basal branch is pegged down in soil at several places.
(4) Tip of a basal branch is pegged down in soil at one place.
Q.23 Formation of sporophyte directly from a gametophyte without involving the
formation and fusion of gametes is known as :
(1) Apospory (2) Recurrent polyembryony
(3) Apogamy (4) Adventive polyembryony
Q.24 Match the following column :
Column–I Column–II
a. Root cutting (i) Clematis
b. Leaf cutting (ii) Duranta
c. Stem cutting (iii) Senseviera
d. Serpentine layering (iv) Blackberry
(1) a-(iii), b-(iv), c-(ii), d-(i) (2) a-(iii), b-(iv), c-(i), d-(ii)

(3) a-(iv), b-(iii), c-(ii), d-(i) (4) a-(iv), b-(iii), c-(i), d-(ii)
Q.25 Which of the following is not correct for asexual reproduction?
(1) The young ones are genetically similar to their parents.
(2) It is uniparental.
(3) It is a slow mode of reproduction.
(4) It involves simple processes of divisions like amitosis and mitosis.
Q.26 Mark the incorrect statement :
(1) Mango tree has a much shorter life span as compared to peepal tree.
(2) There is no natural death in single celled organisms.
(3) The end of vegetative phase marks the beginning of the reproductive phase.
(4) Plant Terror of Bengal was introduced in India because of its tremendous
growth ability.
Q.27 Which of the following is correct w.r.t. arrangement of conidia in Penicillium?
(1) A chain of pigmented conidia is produced at the tip of each phialide.
(2) A chain of non-pigmented conidia is present at the tip of each metuale.
(3) A single conidium is present at the tip of each sterigmata.
(4) A chain of pigmented conidia is present at the tip of each ramus.
Q.28 Which of the following is incorrect w.r.t. zoospores of Chlamydomonas?
(1) They are pyramid shaped and anteriorly biflagellated.
(2) Each Chlamydomonas cell produces 8-16 zoospores.
(3) Zoospore formation occurs during favourable conditions.
(4) Zoospores are thick walled motile spores.
Q.29 Match Column I with Column II
Column I Column II
(Name of plants) (Life span)
a. Peepal (i) 5-7 years
b. Ficus benghalensis (ii) 3000 – 4000 years
c. Red wood tree (iii) 200 years
d. Rose bush (iv) 2000 – 3000 years
(1) a-(iii), b-(iv), c-(ii), d-(i) (2) a-(iv), b-(iii), c-(ii), d-(i)
(3) a-(ii), b-(iii), c-(iv), d-(i) (4) a-(iii), b-(ii), c-(i), d-(iv)
Q.30 Which of the following scientist described sexual reproduction for the first time
in plants?
(1) Bhojwani and Bhatnagar (2) S. Nawaschin
(3) Strasburger (4) R. Camerarius
Q.31 Which of the following is not a feature of artificial/natural methods of
vegetative reproduction?
(1) They are commonly practiced in plant having reduced power of sexual
reproduction.
(2) Superior varieties with poor root system can be propagated.
(3) Yield of progeny is not uniform.
(4) Dispersal is nearly absent.
Q.32 Select an incorrect statement regarding stamen :

(1) Its broader terminal part is called anther.
(2) Each anther lobe has 2 long parallel cylindrical microsporangia.
(3) Whole anther is covered externally by a common epidermis.
(4) Microsporangial or anther development is leptosporangiate type.
Q.33 Which one of the following is true for life span?
(1) Is a specific trait of each organism. (2) Is correlated trait
of each organism.
(3) Is 20 years for a crow. (4) Is related to the complexity of the
organism.
Q.34 Select the incorrect statement :
(1) Both tap and adventitions roots take part in vegetative reproduction.
(2) A detachable somatic part that functions in vegetative reproduction is called
vegetative propagules.
(3) Bulbils and turions are buds which take part in natural propagation.
(4) Eichhornia multiplies by producing special narrow green horizontal branches
which develop at the base of crown and root at intervals.
Q.35 Select incorrect match
(1) Leaf cutting – Snake plant (2) Root cutting – Tamarind
(3) Stem cutting – Blackberry (4) Runner – Lawn grass
Q.36 When two parents (opposite sex) participate in the reproductive process and also
involve fusion of male and female gametes it is called :
(1) Transformation (2) Apogamy (3) Transduction (4) Sexual reproduction
Q.37 Asexual reproduction is common :
(1) Among single celled organisms and plants and animals with relatively simple
organisations.
(2) Among single celled organisms and plants and animals with relatively complex
organisations.
(3) In unicellular organisms only.
(4) In multicellular organisms only.
Q.38 The most common asexual reproductive structures of fungi and algae are
respectively :
(1) Conidia and Zoospore (2) Oidia and Zoospore
(3) Conidia and Aplanospore (4) Parthenospore and Aplanospore
Q.39 In Penicillium conidia production is :
(1) Endogenous and basipetalous (2) Exogenous and basipetalous
(3) Endogenous and acropetalous (4) Exogenous and acropetalous
Q.40 Terror of Bengal was introduced in India because of its :
(1) Very high vegetative reproduction rate (2) Floating speciality
(3) High productivity (4) Beautiful flowers
and shape of leaves
Q.41 Agamospermy means :
(1) Formation of viable seed without meiosis and syngamy.
(2) Formation of viable seed with the help of meiosis and syngamy.

(3) Development of diploid embryo sac.
(4) Occurance of of more than one spore in tetrad
Q.42 Select odd one out (w.r.t. external fertilisation)
(1) Great synchrony between sexes
(2) Large number of offsprings produced
(3) Large number of gametes are released in medium
(4) Offspring are much safe
Q.43 In organisms with haplontic life cycle :
(1) Zygote divides by meiosis (2) Meiocyte divides by meiosis
(3) Zygote divides by mitosis (4) Spore mother cell divides by meiosis
Q.44 Which of the following is incorrect (w.r.t. Chara)?
(1) Sex organs are borne on the adaxial face of the short lateral branch.
(2) Female sex organ occupies a higher position.
(3) Condition is protogynous.
(4) Egg is laden with starch and oil globules.
Q.45 Which of the following is incorrect about asexual reproduction?
(1) New individuals are formed from a single parent
(2) Does not involve fusion of cells
(3) Offsprings are generally similar to the parent
(4) Is a slower method of multiplication
Q.46 Select odd one out (w.r.t.-sexual reproduction)
(1) Sex organ formation is a pre-requisite for sexual reproduction.
(2) Meiosis at the time of sporogenesis.
(3) Is of evolutionary importance.
(4) Does not introduce variability.
Q.47 Grafting is an art of joining parts of two plants, in such a way that there is an
organic union and they grow as one plant. In :
(1) Wedge grafting the stock is cut in the form of solid 'V'.
(2) Side grafting stock and scion having same diameter.
(3) This procedure stock may be inferior quality but physically study.
(4) This procedure stock and scion should lack reserve food.
Q.48 Select incorrect match :
(1) Root cutting – Raspberry (2) Stem cutting – Sugarcane
(3) Serpentine layering – Clematis (4) Air layering – Begonia
Q.49 Select the incorrectly matched pair from the following :
(1) Serpentine layering – Clematis (2) Leaf cutting – Sansevieria
(3) Stem cutting – Strawberry (4) Drop layering – Dwarf Rhododendron
Q.50 Sexual reproducing is different from asexual reproduction in having :
(1) No meiosis for gamete formation
(2) Introduction of genetic variation in population
(3) Quick method of multiplication
(4) Single parent participation

Q.51 Gemmae, specialised asexual buds, are produced in :
(1) Liver worts (2) Yeast (3) Hydra (4) Rhizopus
Q.52 Radical buds develop in :
(1) Bryophyllum (2) Crocus (3) Dalbergia (4) Adiantum
Q.53 Actual fusion of male gamete with egg (syngamy) was observed in Monotropa by :
(1) Nawaschin (2) Strasburger (3) Schleiden (4) Amici
Q.54 In Agave, vegetative reproduction occurs through :
(1) Rhizome (2) Stolon (3) Bulbils (4) Suckers
Q.55 In grafting, stock and scion to be joined by :
(1) Phloem to phloem (2) Xylem to xylem
(3) Pith to pith (4) Cambium to cambium
Answer Key
Section–A
Q.1 4 Q.2 4 Q.3 1 Q.4 2 Q.5 3 Q.6 4 Q.7 1
Q.8 3 Q.9 2 Q.10 2 Q.11 1 Q.12 4 Q.13 3 Q.14 4
Q.15 2 Q.16 1 Q.17 3 Q.18 4 Q.19 4 Q.20 1 Q.21 2
Q.22 2 Q.23 1 Q.24 3 Q.25 3 Q.26 4 Q.27 1 Q.28 4
Q.29 4 Q.30 2 Q.31 2 Q.32 3 Q.33 4 Q.34 4 Q.35 2
Q.36 2 Q.37 4 Q.38 1 Q.39 3 Q.40 2 Q.41 3 Q.42 3
Q.43 2 Q.44 3 Q.45 1 Q.46 2 Q.47 1 Q.48 3 Q.49 4
Q.50 4 Q.51 1 Q.52 3 Q.53 1 Q.54 2 Q.55 1 Q.56 1
Q.57 1 Q.58 1 Q.59 3 Q.60 4
Section–B
Q.1 3 Q.2 2 Q.3 2 Q.4 3 Q.5 2 Q.6 4 Q.7 3
Q.8 1 Q.9 4 Q.10 4 Q.11 4 Q.12 4 Q.13 3 Q.14 2
Q.15 2 Q.16 3 Q.17 3 Q.18 2 Q.19 4 Q.20 2 Q.21 2
Q.22 3 Q.23 3 Q.24 3 Q.25 3 Q.26 4 Q.27 1 Q.28 4

Q.29 2 Q.30 3 Q.31 3 Q.32 4 Q.33 3 Q.34 4 Q.35 3
Q.36 4 Q.37 1 Q.38 1 Q.39 2 Q.40 4 Q.41 1 Q.42 4
Q.43 1 Q.44 3 Q.45 4 Q.46 4 Q.47 3 Q.48 4 Q.49 3
Q.50 2 Q.51 1 Q.52 3 Q.53 2 Q.54 3 Q.55 4

EXERCISE – 2 Previous
Years Questions
Q.1 Reduction division in Angiosperms occurs at the time of [BHU 1995]
(1) Asexual reproduction (2) Gamete formation
(3) Sexual reproduction (4) Zygote germination
Q.2 Formation of zygote without fertilisation is : [CPMT UP 1996]
(1) Parthenocarpy (2) Parthenogenesis (3) Diplospory(4) Apomixis
Q.3 A scion is grafted to a stock. The quality of fruits produced will be determined
by the genotype of :
(1) Stock (2) Scion
(3) Both stock and scion (4) Neither stock nor scion
Q.4 Apomictic embryos in Citrus arise from : [CBSE Pre 2010]
(1) Antipodal cells (2) Diploid egg
(3) Synergids (4) Maternal sporophytic tissue in ovule
Q.5 Transverse binary fission occurs in : [DPMT 2007]
(1) Euglena (2) Amoeba (3) Hydra (4) Paramoecium
Q.6 In which of the following organisms self fertilisation is seen : [Karnat
(1) Fish (2) Roundworm (3) Earthworm (4) Liverfluke
Q.7 Which of the following animals have longitudinal binary fission? [Kerala
(1) Euglena (2) Plasmodium (3) Planaria (4) Paramoecium
Q.8 Which of the following is a hermaphrodite? [Orissa
(1) Ants (2) Earthworm (3) Aphids (4) Cockroach
Q.9 Study of pollen grain is called : [WB JEE 2008]
(1) Ethmology (2) Palynology (3) Paleobotany (4) Co-taxonomy
Q.10 When seeds are attached to parent plant the type of germination is known as :
[Orissa JEE 2008]
(1) Ovipary (2) Epigeal (3) Vivipary (4) Hypogeal
Q.11 External fertilisation occurs in majority of : [DPMT
(1) Algae (2) Fungi (3) Liverworts (4) Mosses
Q.12 Vegetative propagation in mint occurs by : [AIPMT
(1) Offset (2) Rhizome (3) Sucker (4) Runner
Q.13 Vegetative propagation in Pistia occurs by : [AIPMT
(1) Stolon (2) Offset (3) Runner (4) Sucker
Q.14 Which one of the following processes results in the formation of a clone of
bacteria?
[KCET 2010]
(1) Transformation (2) Transduction (3) Binary fission (4) Conjugation
Q.15 Micropropagation is a technique : [KCET 2010]
(1) For production of true to type plants (2) For production of
haploid plants
(3) For production of somatic hybrids (4) For production of somaclonal plants
Q.16 Example of corm is : [AFMC
(1) Ginger (2) Colocasia (3) Onion (4) Potato

Q.17 What is common between vegetative reproduction and apomixes? [AIPMT
(1) Both ar applicable to only dicot plants (2) Both bypass the
flowering phase
(3) Both occur round the year (4) Both produce progeny identical to the
parent
Q.18 Sexual reproduction in fungi may occur by means of : [AMU 2009]
(1) Sporangiospore, oospore and ascospore
(2) Zoospore, oospore and ascospore
(3) Sporangiospore, basidiospore and ascospore
(4) Oospore, ascospore and basidiospore
Q.19 A piece of Potato tuber will form a new plant if it possesses : [CPMT
(1) roots (2) eyes (3) stored food (4) branches
Q.20 Layering is used in vegetative propagation of : [AFMC 1996]
(1) Jasmine (2) Rose (3) Mango (4) All the above
Q.21 Stem cuttings are commonly used in propagation of : [BHU 1998]
(1) Mango (2) Cotton (3) Rose (4) Banana
Q.22 Mango and Guava are propagated through [Har. P
(1) Tissue culture (2) Grafting (3) Stem cuttings (4) Layering
Q.23 First successful animal clone was : [CBSE 2000]
(1) dolly goat (2) dolly sheep (3) molly goat (4) molly sheep
Q.24 Process of fusion of haploid cells is : [HPPMT 2001]
(1) cell cycle (2) meiosis (3) mitosis (4) syngamy
Q.25 The offspring produced through which of the following process are not exactly
similar to their parents? [AFMC
(1) Parthenogenesis (2) Asexual
reproduction
(3) Sexual reproduction (4) Dizygotic twins
Q.26 Adventitive embryony in Citrus is due to : [CBSE 2
(1) egg (2) nucellus (3) embryo(4) integument
Q.27 The formation of gametophyte directly from vegetative cells of sporophye
without meiosis is known as : [AMU 2
(1) Apospory (2) Apogamy (3) Apomixis (4) parthenogamy
Q.28 Despite heterozygosity, the progeny derived from the seed of a cross pollinated
plant was completely uniform. One reason for this may be : [BHU 2
(1) parthenocarpy (2) apomixis
(3) induced mutations (4) polyploidy
Q.29 The technique of obtaining large number of plantlets by tissue culture method is
called
[CBSE 2004]
(1) plantlet culture (2) organ culture (3) micropropagation (4) macropropagation
Q.30 In which one pair both the plants can be vegetatively propagated by leaf pieces?
[DPMT 2003, CBSE 2005]
(1) Bryophyllum and Kalanchoe (2) Chrysanthemum and Agave

(3) Agave and Kalanchoe (4) Asparagus and Bryophyllum
Q.31 In a type of apomixis known as adventive embryony, embryo develops directly
from :
[CBSE 2005]
(1) nucellus or integument cells (2) zygote
(3) synergids/antipodals (4) accessary embryo sac in the ovule
Q.32 Grafting in sugarcane can not be performed because : [AFMC 1998]
(1) vascular bundles are scattered (2) phloem is internal to xylem
(3) sugarcane plant is delicate (4) it is unable to bear injury
Q.33 Development of seed from an unfertilized egg is : [H.P. 2005]
(1) vivipary (2) parthenocarpy (3) apogamy (4) apospory
Q.34 Which one group of plants is propagated through underground roots?[Kerala 2006]
(1) Bryophyllum and Kalanchoe (2) Pistia, Chrysanthemum and Pineapple
(3) Ginger, Potato, Onion, Zamikand (4) Agave, Wild and Oxalis
Q.35 The living organisms can be unexceptionally distinguished from the non-living
things no the basis of their ability for : [CBSE P
(1) reproduction
(2) growth and movement
(3) responsiveness to touch
(4) Interaction with the environment and progressive evolution
Q.36 Male gametes in angiosperms are formed by the division : [CBSE PMT 2007]
(1) vegetative cell (2) microspore mother
(3) microspore (4) generative cell
Q.37 When pollen is transferred from anther of a flower to stigma of another flower
of the same plant it is referred to as : [CBSE PMT 2007]
(1) allogamy (2) xenogamy (3) geitonogamy (4) cross pollination
Q.38 Monoecious plant of Chara shows occurrence of : [AIPMT 2013]
(1) stamen and carpel on the same plant
(2) upper antheridium and lower oogonium on the same plant
(3) upper oogonium and lower antheridium on the same plant
(4) antheridiophore and archegoniophore on the same plant
Q.39 Which one of the following is wrong about Chara ? [AIPMT 2014]
(1) Upper antheridium and lower oogonium
(2) Globule is male reproductive structure
(3) Upper oogonium and lower round antheridium.
(4) Globule and nucule present on the same plant.
ANSWER KEY
Q.1 3 Q.2 2 Q.3 1 Q.4 4 Q.5 4 Q.6 4 Q.7 1
Q.8 3 Q.9 2 Q.10 3 Q.11 1 Q.12 3 Q.13 2 Q.14 3
Q.15 1 Q.16 2 Q.17 4 Q.18 4 Q.19 2 Q.20 1 Q.21 3
Q.22 2 Q.23 2 Q.24 4 Q.25 3 Q.26 2 Q.27 1 Q.28 2
Q.29 3 Q.30 1 Q.31 1 Q.32 1 Q.33 3 Q.34 4 Q.35 1
Q.36 4 Q.37 3 Q.38 3 Q.39 1

EXERCISE – 3 AIIMS
Special Questions
Instructions :
In the following questions, a statement of assertion (A) is followed by a
statement of reason (R).
(1) If both Assertion Reason are true and the reason is the correct explanation
of the assertion, then mark (1).
(2) If both Assertion Reason are true but the reason is not the correct
explanation of the assertion, then mark (2).
(3) If Assertion is true statement but Reason is false, then mark (3).
(4) If both Assertion and Reason are false statements, then mark (4).
Q.1 A : At the end of Juvenility, the organism develops the capacity
to reproduce.
R : It represents the time period between the first and next flowering in
plants.
Q.2 A : Reproduction is a biological process of giving rise to young
ones.
R : Reproduction increases population and maintains the continuity of species.
Q.3 A : Endogamy is common in majority of animals.
R : Fusing gametes are quite different and develop from the same individuals.
Q.4 A : The higher organisms must evolve a special mechanism for
gamete transfer.
R : Male and female gametes are formed in different individuals.
Q.5 A : Air layering will not produce a composite plant.
R : Stock and scion are fused to form a composite plant during approach
grafting.
Q.6 A : Maximum life span Is the characteristic of population.
R : It is the maximum time period upto which a population has survived.
Q.7 A : Reproduction is means of self perpetuation of a race.
R : It introduces variations essential for adaptability and struggle for
existence.
Q.8 A : Asexual reproduction is a rapid mode of reproduction.
R : It plays an important role in evolution.
Q.9 A : Animals are either unisexual or bisexual.
R : Most of bisexual animals reproduce by cross fertilization.
Q.10 A : Development of embryo from the zygote is known as
embryogenesis.
R : Embryogenesis involves cell division and cell differentiation.
Q.11 A : Vegetative reproduction occurs in Dalbergia through tubers.
R : Tubers develop adventitious buds which sprout to form new plants.
Q.12 A : Grafting is possible only in dicots.
R : Dicots have eustelic type of vascular strand.
Q.13 A : Insects visit flowers to gather honey.

R : Dicots have eustelic type of vascular strand.
Q.14 A : Parthenogenesis is a kind of variation of sexual reproduction.
R : In Parthenogenesis, a young one develops from an ovum but without
fertilization.
Q.15 A : All members of bee society are diploid except the drones.
R : Drones are produced parthenogentically.
Q.16 A : Clones are a group organisms of identical genotype, produced
by same kind of sexual reproduction and same sexual processes.
R : These are prepared by group of cells descended from many cells or by
imbreeding of an completely heterozygous line.
Q.17 A : Old age is not a illness. It is a continuous of life with
decreasing capacity for adaptation.
R : Cessation of mitiosis is a normal genetically programmed event.
Q.18 A : The honey bee queen copulates only once in her life time.
R : The honey bee queen lays fertilized as well as unfertilized eggs.
Q.19 A : Ginger has a prostate-growing rhizome.
R : Shoot growth is not affected by gravity.
Q.20 A : Death is regarded as the most important regulatory process
on earth.
R : It avoids over crowding caused by continuous reproduction.
Q.21 A : Grafting is not usually possible in monocots.
R : Successful grafting requires that cambia of both stock and scion fuse to
form new vascular tissues.
Q.22 A : In angiosperms, the ovule develops into a seed after
fertilization.
R : Fertilization is not essential for the development of fruit.
Q.23 A : Viviparous animals give better protection to their offsprings.
R : They lay their egg in safer places in the environment.

Answer Key
Q.1 3 Q.2 2 Q.3 4 Q.4 1 Q.5 2 Q.6 4 Q.7 2
Q.8 3 Q.9 2 Q.10 2 Q.11 4 Q.12 2 Q.13 3 Q.14 1
Q.15 1 Q.16 3 Q.17 3 Q.18 2 Q.19 2 Q.20 1 Q.21 1
Q.22 2 Q.23 3

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