“Any characteristic of an organism or its part which enable it to survive in its own particular habitat is called adaptation”. It is also defined as, “Adaptation is the evolutionary process whereby an organism becomes able to survive and reproduce in its habitat or habitats”. Adaptation is nothing but any changes in the structure or function of an organism or in any parts of its that results from natural selection and by which the organism becomes better fitted to survive and multiply in its environment.
In this presentation, concept of xerophytes, types of xerophytes and adaptations (morphological, anatomical and physiological) developed in them are explained.
In this presentation, concept of hydrophytes, types of hydrophytes and adaptations (morphological, anatomical and physiological) developed in them are explained.
In this presentation, concept of epiphytes, types of epiphytes, and adaptations (morphological, anatomical and physiological) developed in them are are explained.
In this presentation, concept of halophytes, types of halophyte and adaptations (morphological, anatomical and physiological) developed in them are explained
In this presentation, concept of xerophytes, types of xerophytes and adaptations (morphological, anatomical and physiological) developed in them are explained.
In this presentation, concept of hydrophytes, types of hydrophytes and adaptations (morphological, anatomical and physiological) developed in them are explained.
In this presentation, concept of epiphytes, types of epiphytes, and adaptations (morphological, anatomical and physiological) developed in them are are explained.
In this presentation, concept of halophytes, types of halophyte and adaptations (morphological, anatomical and physiological) developed in them are explained
economic importance of gymnosperms.Gymnosperms are simple and primitive seed-bearing plants without flowers.
The plant body is sporophytic and is differentiated into root,stem and leaves.
All gymnosperms are usually wind-pollinated.
Leaves have thick cuticle and sunken stomata.
Gymnosperms are heterosporous.magasporangia and microsporangia occur on mega and microsporophylls respectively.
A hydrosere is a plant succession which occurs in an area of fresh water such as in oxbow lakes and kettle lakes.
Dr. K. Rama Rao
Govt. Degree College
TEKKALI; Srikakulam Dt. A. P
Phone: 9010705687
Ecology is the scientific study of organisms `at home' which is called as the `environment'. The term `environment' refers to those parts of the world or the total set of circumstances which surround an organism or a group of organisms.
economic importance of gymnosperms.Gymnosperms are simple and primitive seed-bearing plants without flowers.
The plant body is sporophytic and is differentiated into root,stem and leaves.
All gymnosperms are usually wind-pollinated.
Leaves have thick cuticle and sunken stomata.
Gymnosperms are heterosporous.magasporangia and microsporangia occur on mega and microsporophylls respectively.
A hydrosere is a plant succession which occurs in an area of fresh water such as in oxbow lakes and kettle lakes.
Dr. K. Rama Rao
Govt. Degree College
TEKKALI; Srikakulam Dt. A. P
Phone: 9010705687
Ecology is the scientific study of organisms `at home' which is called as the `environment'. The term `environment' refers to those parts of the world or the total set of circumstances which surround an organism or a group of organisms.
Lecture 1 definition, classification of marine hydrophytesBirJoyanta
Lecture for Undergraduate student of Fisheries and Marine Science Department. This lecture will focus on hydrophytes, its types and different adaptation strategies. I collected info from internet and some of author that i mention on the last slide of this lecture. Hope it will be useful for graduate student.
The term "algae" covers many different organisms capable of producing oxygen through photosynthesis (the process of harvesting light energy from the sun to generate carbohydrates).
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Introduction: Biotechnology is an emerging field of research as it has the potential to solve many biological problems which could not be solved till now with conventional techniques.
The use of biology to develop technologies and products for the welfare of human beings is known as Biotechnology. It has various applications in different fields such as Therapeutics, Diagnostics, Processed Food, Waste Management, Energy Production, Genetically Modified Crops etc.
Biotechnology means 'applications of scientific and engineering principles to biological processes to provide goods and services'. Full understanding of biological processes is possible with detailed analysis of gene structure and function i.e. the Genetic Engineering means the introduction of manipulated genetic material (DNA) into a cell in such a way as to replicate and be passed on to progeny cells'. The outcome is attractive and promising.
Sex-determination and Sex-linked Inheritance.pptxSeemaGaikwad15
The sexually reproducing organisms are classified into two types such as monoecious (hermaphrodite) and dioecious. In monoecious organisms, both male and female gametes (sex cells) are produced by a single individual. The organisms in which both male and female gametes are produced by different individuals are called dioecious. Living organisms, with a very few exceptions, are differentiated into male and female individuals. The sexes of the individuals are genetically determined.
The biological system that determines the development of sexual characteristics in an organism is called sex determination.
There are two different systems of sex determination- Chromosomal sex determination and Non-genetic sex determination.
Natural products are chemical compounds or substances produced naturally by living organisms. With the development of modern technology, more and more plant extracts have been found to be useful to medical practice. Natural products can be divided into two major classes, primary metabolites, which are required for an organism to survive, and secondary metabolites, which are not required for an organism to survive, but usually lend the organism some form of growth or survival advantage within its environment.
Medicinal plants are considered as a rich resources of ingredients which can be used in drug development. More than 30% of the entire plant species, at one time or other were used for medicinal purposes. It has been estimated that in developed countries like United States, plant drugs constitute as much as 25% of the total drugs, while in fast developing countries like India and China the contribution is as much as 80%. These countries provide two third of the plants used in modern system of medicine and the health care system of rural population depend on indigenous systems of medicine. Most of the drugs are considered very safe as there is no or minimal side effects.
Food is synthesized in the green parts of a plant. The non-green parts are depended on the photosynthetic cells for nourishment. The main function of photosynthesis is to provide energy and carbon skeleton to all living cells in different regions of organs of plant body. The food in the form of sucrose is transported by the vascular tissue phloem. The transport of photosynthetic organic substance from leaf to any organ at relatively long distance is called translocation. Such translocation of organic substances occurs through a vascular tissue called phloem. The translocation of organic substances through phloem tissue is called phloem transport.
Photosynthesis is important to living organisms because it is the number one source of oxygen in the atmosphere. Almost all the oxygen in the atmosphere is due to the process of photosynthesis. If photosynthesis ceased, there would soon be little food or other organic matter on Earth, most organisms would disappear, and Earth’s atmosphere would eventually become nearly devoid of gaseous oxygen.
Plant growth regulators are organic compounds, either natural, or synthetic, that modify or control one or more specific physiological processes with a plant. Natural plant growth regulators are produced by plants and to differentiate these from hormones in animals, the term plant hormones or phytohormones is used for such substances. Plant hormones are naturally occurring compounds produced by the plant to accelerate or retard the rate of growth or maturation.
Nitrogen is important element of life. In importance it comes only next to carbon, hydrogen, and oxygen. The composition of protein, nucleic acid, growth hormones, and vitamins requires Nitrogen. Leaves consist of about 1 to 15% nitrogen of their dry weight but lesser % in another vegetative organ.
• The N2 is present in the atmosphere, in the form of gas. It is about 78%.
• Green plants unable to use this N2 directly in their metabolism. Only some micro-organism can convert this N2 gas directly into organic form.
• The N2 present in the soil is called soil nitrogen. The plants growing in the soil, mainly utilize the soil N2 for their metabolic requirements.
• In the soil the nitrogen is present in the form of nitrate nitrogen (NO3, NO2), ammonia nitrogen (ammonia, ammonium salt), organic nitrogen and molecular nitrogen (N2).
• The converging of the free nitrogen, by natural or physical process is called nitrogen fixation… when any biological system is involved in this process, then it is called as biological nitrogen fixation……
The main causes of ecological succession include the biotic and climatic factors that can destroy the populations of an area. Wind, fire, soil erosion and natural disasters include the climatic factors. Ecological succession is important for the growth and development of an ecosystem. It initiates colonization of new areas and recolonization of the areas that had been destroyed due to certain biotic and climatic factors. Thus, the organisms can adapt to the changes and learn to survive in a changing environment.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
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Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
How to Create Map Views in the Odoo 17 ERPCeline George
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The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
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http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
2024.06.01 Introducing a competency framework for languag learning materials ...
Ecological Adaptation ppt.pptx
1. B.Sc. I, Sem. II, Paper III
PLANT ECOLOGY
Associate Professor, Dr. S. A. Gaikwad
Dept. of Botany
Vidnyan Mahavidyalaya, Sangola
2. Ecological adaptation
Adaptations in an organism or in the community are generally for the changes in the entire
environment. The organisms adapt to the changes in the surrounding atmosphere because of the
basic property of the protoplasm, known as the adaptability. The adaptability helps the organisms
to remain in the process of evolution. The ecological adaptations are the responses shown by the
plants to the environmental conditions and they are the adjustments as per environmental changes.
“The changes in the characters, which enable the organisms to withstand the changes in the
surrounding environment and to make use of these changes for the maximum benefits, are
known as adaptations.”
The adaptations which are induced by water factor or availability of water in the environment are
of three types – xeric, hydric and mesic. These terms are used for the environmental conditions
which are responsible for respective adaptations.
3. Ecological adaptation
All adaptations may be structural, physiological or behavioral, are the result of evolution, which is a
change in a species over thousands of years or within a few lifetimes. The life cycle of any organism
is controlled by number of environmental factors. Water is the most essential factor for every living
organism. Plants growing under different environmental conditions exhibit various adaptation. For the
first time, Warming (1895) had realized the impact of different factors upon the vegetation in ecology
and he classified plants on the basis of nature of substratum on which they grow. Later on, Warming
(1909) classified the plants on the basis of their water requirements. The plants are divided into three
major groups as per their water requirements- 1. Hydrophytes- Plants growing in abundant water i.e.,
in maximum water supply and near the water, 2. Xerophytes- Plants growing in dry, arid region
which shows shortage of water in the soil i.e., in minimum supply of water, 3. Mesophytes- Plants
growing in habitat with neither less nor more water is available i.e., moderate water supply is
required.
4. Ecological adaptation - Hydric adaptation
Plants are either growing on land or in water. The land plants get essential water from the soil but the
aquatic plants are growing within or near the water. On the basis of availability of water, the adaptations
are of three types – Xeric, Hydric and Mesic.
A. Hydric Adaptations:
1. Water availability is far more than the requirement of plants.
2. There is no need of mechanical strengthening as plants are supported by water all around them.
3. Aquatic plants can only grow partially or completely in water or in soil that is permanently saturated
with water.
4. The habitat of aquatic plants is either fresh water or marine.
5. Underwater leaves and stems are flexible to move with water currents.
As the plants are growing in hydric conditions these are known as hydrophytes (Hydro- water, phytes -
plants). There are three different types of hydrophytes -
5. Ecological adaptation- Hydric adaptation
As the plants are growing in hydric conditions these are known as hydrophytes (Hydro- water,
phytes -plants). There are three different types of hydrophytes -
a. Submerged hydrophytes- Plants are b. Floating hydrophytes – These are of two types
growing under the water surface 1.Free floating hydrophytes: Freely floats on the water
e.g., Hydrilla, Potamogeton, Utricularia surface, not rooted in the soil e.g., Eichhornia, Pistia.
6. Ecological adaptation- Hydric adaptation
2. Floating but rooted hydrophytes: Plants are
rooted in the soil but leaves are floating on the
surface of water e.g. Nymphaea, Marsilea.
c. Amphibious hydrophytes - These are growing
in shallow water or in muddy soil i.e., in marshy
places e.g. Cyperus, Typha
All these hydrophytes have certain morphological, anatomical and physiological modifications
while growing in above aquatic conditions. These modifications are known as hydrophytic
adaptations which are discussed below-
8. Ecological adaptation- Hydric adaptation
• Roots: Root system of hydrophytes is not of much
importance, because they grow partially or
completely in water.
• Roots are poorly developed (e.g., Hydrilla,
Vallisneria.), reduced or completely absent (e.g.,
Utricularia, Ceratophyllum,).
• However, some hydrophytes have well developed
adventitious roots (e.g., Eichhornia, Pistia).
• Root caps usually absent. Root hairs are poorly
developed in most hydrophytes.
• Root tips are often provided with root pockets (e.g.,
Eichhornia).
Stem: In submerged hydrophytes, the stem is long,
slender thin, spongy and flexible e.g., Hydrilla.
• In free floating hydrophytes, the stem or stolon is
horizontal, spongy, thick and short, floating on the
surface of water e.g., Eichhornia, Azolla, Pistia
• while in rooted hydrophytes like Nymphaea,
Nelumbium, Cyperus, the stem is a rhizome. These
rhizomes live for many years and produce leaves
every year.
• Mucilaginous or waxy coating is present on entire
plant body.
Morphological(External)adaptations of Hydrophytes:
9. Ecological adaptation- Hydric adaptation
Morphological adaptations of Hydrophytes:
Petioles:
• Some floating hydrophytes show special
features in the petioles.
• In free floating but rooted hydrophytes
like Nymphaea and Nelumbium, petioles
are long, slender and spongy
• while they are swollen, spongy in free
floating hydrophyte like Eichhornia,
helps in floating.
Leaves:
• The leaves are thin, long or ribbon like (e.g.,
Vallisnaria). linear (e.g., Potamogaton) or finally
dissected (e.g., Ceratophyllum).
• The leaves may be long, flat, and entire as in
Nelumbo, Nymphaea.
• The petioles are long swollen and spongy (e.g.,
Eichhornia, Trapa).
• Heterophylly is observed in some plants.
Generally, the leaves are reduced in thickness and
covered by waxy coating.
10. Anatomical (Internal) adaptations of Hydrophytes: Leaves:
Root:
Cuticle is very thin or absent.
Root hairs present in amphibious hydrophytes.
Epidermis is single layered made up of thin-
walled cells. Parenchymatous cortex i.e.,
arenchyma is well developed. It has numerous
air chambers which help in buoyancy
(floating) and rapid gaseous exchange.
Conducting tissues, i.e., xylem and phloem,
developed poorly and less differentiated. Only
xylem tracheids are present in submerged
forms while phloem is well differentiated in
amphibious hydrophytes.
Mechanical tissues are generally absent. Pith
is absent.
Cuticle is absent or poorly developed in Nymphaea leaves.
Epidermis is single layered with thin walled parenchymatous cells.
Chlorophyll found in all the tissues. Epidermal cells of leaves contain
abundant chloroplasts and they can function as photosynthetic tissue,
especially where the leaves and stems are very thin e.g., Hydrilla.
Stomata are totally absent in submerged plants, but in floating leaves,
stomata are present on the upper surface. In amphibious plants stomata
may be scattered on all the aerial parts.
In submerged plants, mesophyll tissues are not differentiated while in
other forms of hydrophytes these are well differentiated into spongy
parenchyma and palisade tissues. They show air cavities.
In submerged leaves, air chambers are filled with respiratory and other
gases.
Mucilage canals and mucilage cells are present which secrete mucilage to
protect the plant body. Mechanical tissues are poorly developed or
completely absent.
11. Ecological adaptation- Hydric adaptation
Anatomical (Internal) adaptations of Hydrophytes:
Stem:
Cuticle is very thin, poorly developed or absent.
Epidermis is single layered with thin walled parenchymatous cells.
The rhizome of Nymphaea and stem of Typha shows well developed
epidermis.
In floating forms, thin walled parenchymatous or collenchymatous
hypodermis is present which is containing chloroplasts.
Parenchymatous cortex is well developed with number of air chambers
which help in buoyancy (floating) and rapid gaseous exchange.
Endodermis and pericycle is generally distinct.
The vascular tissues, i.e., xylem and phloem, developed poorly, thin
walled except in amphibious hydrophytes.
Mechanical tissues are poorly developed or absent.
12. Ecological adaptation- Hydric adaptation
Physiological Adaptations of Hydrophytes:
Osmotic concentrations of cell sap are low.
Entire plant surface absorbs water and nutrients.
Hydrophytes maintain active photosynthesis as chloroplasts are
distributed throughout the plant body.
CO2 and O2 evolved during respiration and photosynthesis is stored in
air chambers for future use.
No transpiration from submerged plants.
13. Ecological adaptation- Xeric adaptation
As the plants are growing in xeric conditions these are known as xerophytes.
There are three different types of xerophytes -
a. Drought escaping plants (Ephemerals) - These are also called as drought
evaders which have a very short life cycle i.e., they are annuals, to avoid the
drought e.g. Tribulus terrestris, Argemone mexicana, Cassia tora etc.
b. Drought tolerant/enduring plants (succulents) - They store large
amount of water in different organs of their body, so they become
fleshy. They are called succulents. The stem succulents store water
in stem so it becomes fleshy, green and photosynthetic leaves are
reduced to spines e. g. Opuntia. In leaf succulents store water in
leaves and they become thick
fleshy as in Aloe, Portulaca.
1. Water availability in the soil is very low
than the requirement of plants.
2. The temperature is very high so
humidity is less which results in the loss
of water.
3. Arid, dry area with low rainfall,
4. Hot, dry climate is responsible for
increasing evaporation and transpiration.
5. All these environmental conditions are
responsible for drought in that habitat
14. Ecological adaptation- Xeric adaptation
c. Drought resisting plants (Non- succulents) - These
plants are the true xerophytes. They resist the drought
by showing external and internal adaptations to dry
conditions. Examples are Calotropis, Casuarina,
Nerium, Acacia.
15. Ecological adaptation- Xeric adaptation
Stem:
• The stem is hard, woody either aerial or subterranean, sometimes
covered with wax e.g., Equisetum.
• Stem may be covered with dense hairs as in Calotropis or thorns. In
some succulents, it is bulbous and fleshy.
• The extreme xerophytes like Opuntia, stem is modified into leaf like,
flattened fleshy structure known as phylloclade while in Asparagus it
is modified into small needle-like green structures exactly looking like
leaves called as cladodes. Both phylloclade and cladodes perform the
function of leaf i.e., photosynthesis.
Morphological adaptations of xerophytes:
Root:
• Root system is well developed and
profusely branched.
• The roots of perennial xerophytes
grow deep into the ground that can
penetrate several meters down where
plenty of water is available.
• Most of the desert plants like Cacti
develop superficial and shallow root
system which is able to absorb water
that is available near the surface of the
earth.
16. Morphological adaptations of xerophytes: Ecological adaptation- Xeric adaptation
Leaves:
• Leaves are thick and leathery, tough, shining (Nerium)
or may be thick, fleshy & succulent (Aloe).
• In some plants like Cacti, leaves are reduced, usually
small and fall off during prolonged dry conditions to
prevent water loss by simply losing their leaves,
absent or modified into spines (Zizyphus, Capparis,
Acacia).
• Leaf lamina may be long, narrow needle like as in
Pinus or divided into many leaflets like Acacia, leaf
apex & margin is spiny (Aloe).
• Curled leaves are present in some extreme xerophytic
grasses. The rolling or folding of leaves minimizing
the evaporation and water loss.
18. Anatomical adaptations of xerophytes: Ecological adaptation- Xeric adaptation
Roots:
Root cap is present. Root hairs are
large in number.
Conducting tissues, i.e., xylem
and phloem, developed very well.
Thick cuticle is present which
protects internal tissues from dry
and hot soils.
Stem:
Epidermis is thick walled and lignified.
Some plants show wax deposition on the surface of
epidermis and even in the hypodermis.
In succulent stems, thin walled parenchymatous
cells store excess amount of water, mucilage, latex,
etc. called water storage tissues.
Woody xerophytes produce very well-developed
cork in the stem.
Mechanical tissues and vascular tissues are well
developed.
19. Anatomical adaptations of xerophytes: Ecological adaptation- Xeric adaptation
Leaves:
Epidermis with thick cuticle & epidermal cells are
thick walled.
Multilayered epidermis is present on both upper and
lower surface of leaves.
Sunken stomata are present and stomatal opening is
covered with number of hairs, presence of many
layered palisade tissue.
Mesophyll is very compact with reduced intercellular
spaces.
In succulent leaves, spongy parenchyma i.e., water
storage tissue stores water.
Thick-walled sclerenchyma cells are seen in the
hypodermis e.g., Pinus needle.
Well-developed vascular and mechanical tissues are
present.
20. Ecological adaptation- Xeric adaptation
Physiological Adaptations of Xerophytes:
The stomata of these plants open during night hours and remain closed during the day to
prevent water loss by reducing evaporation rate.
The xerophytes have very high osmotic pressure of the cell sap, which increases the turgidity of
the cell sap.
These plants control the excessive loss of water during transpiration by reducing total
transpiring surface,
Xerophytes have greater potentiality to resist wilting.
The protoplasm in these plants is less viscous and more permeable and resistant to heat.
These plants may secrete resins and waxes (epicuticular wax) on their surfaces, which reduce
evaporation.