occurrence and physiological characteristics of algae and its use in cosmetic field and other industries.

1. ALGAE
By:- Khushbu
shrivastava

2. INTRODUCTION
1. The term algae was proposed by linnaeus in 1753 but he had
used this term for those organisms which we call bryophytes
now a days.
2. A.L.de Jussieu (1789) was first to use it for those organisms
which we now believe to be algae.
3. Algae is a term that describes a large and incredibly diverse
group of eukaryotic, photosynthetic life forms. These
organisms do not share a common ancestor and hence, are
not related to each other (polyphyletic)
4. Algae can be multicellular or unicellular.
5. Most of the multicellular algae placed in kingdom
PLANTAE and few unicellular algae are placed in kingdom
PROTISTA.
6. PLANTAE - blue green algae, giant kelp and brown algae
PROTISTA - diatoms, euglenoids ,Dinoflagellates
1. The branch of botany dealing with the study of algae is
known as phycology or algology.
2. It is derived from the greek word phykos which means
‘alga’ or ‘seaweed’.

3. Occurrence
of algae
● Algae are commonly presumed to be occurring in water
and moist places but algae are found in a variety of
habitats.
● The common places of occurrence of algae are as
follows:-
1. AQUATIC ALGAE:-
2. Fresh water forms- are found in water of low salinity
such as in ponds, lakes, rivers, ditches etc.
● Cladophora,, vaucheria, chara and some algae found
in slow running water while spirogyra,
chlamydomonas, hydrodictyon and volvox are found
in stagnant water.
1. Marine forms- algae found in seawater are called
marine algae.
● Such algae grow in water of high salinity.marine algae
can be macroscopic and very large in size eg:-
Macrocystic (70m) and nereocystis (100m), viva,
enteromorpha, sargassum etc.

4. Occurrence
of algae
2. TERRESTRIAL ALGAE:-
● Algae growing on moist soil surfaces, stones
and rocks are terrestrial algae.
● The algae growing on surface of soil are called
saprophytes.
● The algae growing under the surface of soil are
called cryptophytes.
● Some terrestrial algae grow on moist walls and
barks of trees, these algae absorb carbon
dioxide and water from atmosphere.
● Eg:- Fritschiella, vaucheria, chlorella and
oscillatoria.

5. Occurrence of algae.
3. LITHOPHYTIC ALGAE:- algae growing on surface of
rocks and stones are lithophytic eg:- Nostoc,
Gloeocapsa.
4. HALOPHYTIC ALGAE:- algae growing in water of high
concentration of salt lakes are halophytic algae eg:-
Chlamydomonas ehrenbergii and Dunaliella.
5. THERMOPHYTIC ALGAE:- the algae grow in water of
high temp. Where other plants forms cannot grow, some
blue-green algae are capable of growing at very high
temp. Eg:- Oscillatoria, Tere piriformis,
Heterohotmogonium, etc.
6. CRYOPHYTIC ALGAE:- algae occurring in snow and
ice are crophytic algae. These algae impart special color to
the snow due their pigments. Red snow - Haematococcus
Nivalis
Green snow- Chlamydomonas yellowstonensis
7. EPIPHYTIC ALGAE:- algae growing on other algae and
plants are called epiphytic algae eg:-
8. EPIZOIC ALGAE:- algae growing on other animals are called
epizoic algae eg:- Cladophora crisposa grows on snails,
Stigeoclonium grows on gills of fishes.
9. ENDOPHYTIC ALGAE:- algae growing inside other plants are
called endophytic algae eg:- nostoc is found in thallus of
anthoceros.
10. ENDOZOIC ALGAE:- algae found inside the body of animals
are endozoic algae eg:- Zoo chlorella is found in hydra and
sponges, some blue-green algae found in respiratory tract of
animals.
11. PARASITIC ALGAE:-some algaes can be found as parasites
on plants and animals eg:- cephaleuros is found on leaves of
tea.
12. SYMBIOTIC ALGAE:-some algae of chlorophyceae and
cyanophyceae are found in symbiotic association with other
plants. Lichens are symbiotic association with algae and fungi.
13. PLANKTONS:- algae growing on surface of water and found
as free floating on surface of water are called planktons. When
planktonic algae grow fast and increase enormously in number
these algae form water blooms.

6. General characteristics of algae.
1. It consist of chlorophyll and other pigments for carrying out photosynthesis. (photoautotrophs)
2. Most algae require a moist or watery environment; hence, they are ubiquitous near or inside water
bodies.
3. Anatomically, they are similar to another major group of photosynthetic organisms – the land
plants. However, that is where the differences end as algae lack many structural components
typically present in plants, such as true stems, shoots, and leaves.
4. Furthermore, they also do not have vascular tissues to circulate essential nutrients and water
throughout their body.
5. they possess specialized structures and cell-organelles,like centrioles and flagella, found only in
animals.
6. Reproduction in algae occurs in both asexual and sexual forms.
7. Range in size from microscopic to single celled organisms to large seaweed.

7. General characteristics of algae.
8. Algae are free-living, although some can form a symbiotic relationship with other organisms.
9. Cell wall is thin and rigid and require carbondioxide and light as their principal source of energy.
10. Motile algae such as euglena have flexible cell membrane called periplasm.
11. Cell wall of many algae are surrounded by a flexible gelatinous outer matrix.
12. Discrete nucleus is present and inclusion like starch granules, oil droplets and vacuoles are present.
13. Chloroplasts may occur one, two or many per cell they may be ribbon like, bar like, net like or as discrete
discs.

8. Morphology of algae
1. The eukaryotic algae cell is surrounded by a thin rigid cell wall.
2. The cell wall of the algae is made up of cellulose,
hemicellulose,mucilage,pectin and other substances like alginic
acid,fucoidan,fucin,calcium carbonate,silica etc.
3. Some algae contain a stout and strong plasma membrane
4. The nucleus of eukaryotic algae is well organised. The nucleus is
surrounded by a double-layered nuclear membrane. The inner
side of the membrane is occupied by a chromatin reticulum
embedded in a matrix called karyolymph. The outer side of the
nuclear membrane is continuous with the endoplasmic reticulum.
5. The nucleus contains one, two or more nucleoli or endosomes,
the number varies in different algae.
6. The eukaryotic algae contain membrane-bound organelles such as
chloroplasts, mitochondria, golgi apparatus, endoplasmic reticu-
lum and, in some cases, eye spot or stigma.
7. The eye-spot or stigma is a motile vegetative and reproductive cell
and contain pigments spots in anterior,middle or posterior part of the
cell
8. Chloroplast is a double-membrane structure containing
photosynthetic pigments.
9. A disc like structure is formed from the internal lamellar system
which are stacked together to form grana. This disc is a sac or
vesicle and known as thylakoid, which are encloses an inner
thylakoid space.

9. FLAGELLA (motility)
1. Motile vegetative or reproductive algal cells perform
their locomotion or movement by using thread-like
protoplasmic appendages known as the flagella.
Mainly two types of flagella have been identified in
algae such as;
A.Whiplash or Acronematic is a hairless and smooth
surfaced-.flagella
B.. Tinsel or Pleuronematic contain one or more rows of
lateral fine filamentous hairs called mastigonemes or
flimmers.
There are also other types of flagella such as;
● Pantonematic: mastigonemes are arranged in two
opposite rows.
● Pantoacronematic: When Pantonematic flagella
contain a terminal fibril is known as
pantoacronematic.
● Stichonematic: contain one-sided mastigonemes.

10. Reproduction in algae
ASEXUAL REPRODUCTION
1. It is a process of formation of progeny
without the union of cell or nuclear material.
2. Some unicellular algae reproduce asexually
by any of these 3 process:-
● Fragmentation
● Zoospores
● Binary fission
SEXUAL REPRODUCTION.
1. Sexual reproduction is characterized by the
process of meiosis, in which progeny cells
receive half of their genetic information from
each parent cell.
2. A sexually reproducing organism typically has
two phases in its life cycle. In the first stage,
each cell has a single set of chromosomes and
is called haploid, whereas in the second stage
each cell has two sets of chromosomes and is
called diploid
3. When one haploid gamete fuses with another
haploid gamete during fertilization, the
resulting combination, with two sets of
chromosomes, is called a zygote.
4. a diploid cell directly or indirectly undergoes a
special reductive cell-division process
(meiosis)
5. During meiosis the chromosome number
of a diploid sporophyte is halved, and the
resulting daughter cells are haploid.

11. Life-cycle of
algae

12. classification of algae
Based on seven major divisions.
1. Nature and properties of pigment.
2. Chemistry of reserve food products.
3. Morphology of flagella.
4. Morphology of cells and thalli.
5. Life history reproductive structure and methods of reproduction.
6. Food storage substance.
7. Cell wall composition.

13. DIVIDED INTO 9 PHYLA
1. Phylum Rhodophyta
2. Phylum Xantho Phycophyta
3. Phylum chrysophycophyta
4. Phylum phaeo phycophyta
5. Phylum bacillariophyta
6. Phylum euglenophyta
7. Phylum chlorophycophyta
8. Phylum crypto phycophyta
9. Phylum pyrrophycophyta

14. 1. PHYLUM RHODE
PHYCOPHYTA
+4000 species of RED
ALGAE
1. The red algae are commonly found in tropical
marine locations.
2. Unlike other algae, these eukaryotic cells lack
flagella and centrioles.
3. they grow on solid surfaces including tropical
reefs or attached to other algae.
4. Their cell walls consist of cellulose and many
different types of carbohydrates.
5. These algae reproduce asexually by monospores
(walled, spherical cells without flagella) that are
carried by water currents until germination.
6. Red algae also reproduce sexually and undergo
alternation of generation.
7. Red algae form a number of different seaweed
types.
8. Smaller than brown algae and often found at a
depth of 200 meters.
9. Contain chlorophyll a and d as well as phycobilins
which are important in absorbing light that can
penetrate deep into the water.
10. Have cells coated in carrageenan which is used in
cosmetics, gelatin capsules and some cheeses.
11. Red algae GELIDIUM is the one from which
AGAR is made.

15. 2. PHYLUM XANTHO
PHYCOPHYTA
450-460 species of YELLOW
GREEN ALGAE
1. Yellow green algae are the least prolific
species of algae.
2. They are unicellular organisms with cell
walls made of cellulose, pectin and silica,
they contain 1-2 flagella for motion.
3. Their chloroplast lacks a certain pigment,
which cause them to appear lighter in
color.
4. They usually form in small colonies of only
a few cells.
5. Yellow-green algae typically live in
freshwater, but can be found in salt water
and wet soil environments.
6. Chlorophyll a,c and rarely e are present.
7. Cellular storage product is
chrysolaminarin.
8. Flagella unequal in length.
9. Asexual reproduction by cell division and
fragmentation
10. VAUCHERIA is a well known member of
this division.

16. 3.PHYLUM
CHRYSOPHYCOPHYTA
100,000+ species of GOLDEN
ALGAE
1. Golden- algae are the most
abundant types of unicellular algae,
2. They are found in fresh and salt water
environments.
3. Predominantly flagellates some are
amoeboid
4. Chlorophyll a and c present
5. Reserve food as chrysolaminarin and
their frequent incorporation of silica
6. Characteristic color due to masking of
their chlorophyll by brown pigments and
because of presence of carotenoid pigment.
7. Reproduction is commonly asexual but
at times isogamous.

17. 4. PHYLUM PHAEO
PHYCOPHYTA
1500 species of BROWN
ALGAE
1. Brown algae are among the largest
species of algae,consisting of varieties
of seaweed and kelp found in marine
environments.
2. All are multicellular and large (often
reaching lengths of 147 ft.)
3. Individual alga may grow to a length of
100m with a holdfast, stripe and blade.
4. These species have differentiated
tissues,including an anchoring organ,
air pockets for buoyancy, a stalk,
photosynthetic organs,and reproductive
tissues that produce spores and
gametes.
5. Chlorophyll a and c present
6. Some examples of brown species
include sargassum weed, rockweed,
and giant kelp (100 m).
7. Used in cosmetics and most ice
creams.

18. 5. PHYLUM
BACILLARIOPHYTA
THE DIATOMS
1. Diatoms are found in fresh
water as well as in salt
water.
2. Diatoms provide abundant
food supply for aquatic
animals.
3. Chlorophyll a and c present.
4. Shells of diatoms are called
frustules.
5. Deposits of these shells
from centuries of growth are
called diatomite or
diatomaceous earth.

19. 6. PHYLUM EUGLENOPHYTA
1000 species of euglenoids
1. Unicellular and motile by means of
flagella
2. Chlorophyll a and b present
3. Have both plant like and animal like
characteristics
4. They lack a cell wall but instead are
covered by a protein-rich layer
called the pellicle.
5. It consist of eyespot, flagella, and
organelles (nucleus, chloroplasts,
and vacuole).
6. Reproduction by longitudinal binary
fission
7. Carry out photosynthesis in
chloroplast and is facultatively
autotrophic.

20. 7. PHYLUM
CHLOROPHYCOPHYTA
7000 species of GREEN ALGAE
1. Green algae mostly found in freshwater and
some species can be found in the ocean.
2. It has cell wall made up of cellulose and some
species have one or two flagella.
3. Both green algae and land plants have
chlorophyll a and b as well as carotenoids and
store food as starch.
4. There are thousands of unicellular and
multicellular species of these algae.
5. Multicellular species usually group in colonies
ranging in size from 4 cells to several
thousand cells.
6. For reproduction some species produce non-
motile the rely on water currents while others
produce zoospores with 1 flagellum for
swimming to a more favorable environment
7. Examples of green algae includes sea lettuce,
horsehair algae, and dead man’s fingers.

21. 8. PHYLUM
CRYPTOPHYCOPHTA
1. Cryptomonas are
biflagellate organisms
2. Cells are slipper shaped
and flattened occur singly.
3. Some with cellulose wall
others naked
4. There are 1 or 2 plastids
with or without pyrenoids.
5. Reproduction by longitudinal
cell division or by zoospores
or cysts.

22. 9. PHYLUM
PYRROPHYCOPHYTA
1. Flagella are inserted in the
girdle and arranged with one
encircling the cell and other
trailing
2. Many are covered only by
plasmalemma and in some
there is a wall made of
cellulose
3. Some have series of cellulose
plates with in plasmalemma
termed thecal plates
4. Dinoflagellates a diverse
group of biflagellates
unicellular organisms
present.

23. IMPORTANCE

24. Thank you