ADAPTATION

Adaptation is the capacity possessed by living organisms to live successfully in certain habitats within   the limits of prevailing environmental factors in such habitats. It is  also described as any feature an organism possesses that increases its chances of survival in that habitat.

They can be displayedin three main features of organism

1 Structural adaptation;Is the modification of different parts of the body of organisms for special functions which enhance the success or survival of such organism in their environment. Examples include limbs of vertebrates adapted for movements, the teeth of mammals which are adapted for different diets etc.

2 Physiological adaptations; Are the special ability or features of the life processes of organisms which are meant to enhance their survival. For instance the production of appropriate enzymes for their metabolic activities, the different methods of regulating water content of the body of organisms, the diverse methods of responding to different stimuli, the various ways of eliminating waste products of metabolism, etc.

3 Behavioraladaptations; Are the expression of different actions or activities by organisms in order to survive in their environment. Examples include migratory movements seen in some species of birds, fishes and mammals, mimicry in butterflies, chameleons, encystment in certain protozoa, aestivation by snail, etc.

ADAPTATION OF PLANTS TO AQUATIC HABITATS

1. Some plants have breathing roots or pneumatophores for gas exchange egRaphia palm

2. Possession of air space in the tissues for buoyancy eg water lettuce

3. Possession of waxy cuticles on leaves to prevent wetting eg water lettuce

4. Possession of long stems and flower stalks to expose the flowers and leaves eg water lettuce

5. Absence of typical roots but adventitious roots or rhizoids may be present eg water lettuce

6. Some plants have air floats on their leaves, stems and petioles which keep them buoyant eg water hyacinth

ADAPTATION OF PLANTS TO TERRESTRIAL HABITATS

1. Many plants have thick waxy cuticles or hairs on leaves to prevent water loss due to transpiration

2. They also have thick barks on the stems to protect the tissues. In tropical savannas, such barks protects the plants from the annual fire attacks

3. Some leaves are modified into thorns (eg Euphorbia) or reduced in size to prevent excessive water loss eg whistling pine

4. Some leaves have sunken stomata (egsahara grass) or reduced number of stomata to reduce water loss

5. Some leaves are reduced into  spines, tiny and scanty leaves (eg cactus) while many desert plants are leafless

6. Possession of thickened and succulent stems for water storage egBryophyllum

7. Possession of extensive root system. Many plants that live in arid regions (eg hot deserts) have many roots which grow deep into the soil and spread out to increase their chances of tapping deep water supplies

8. Possession of numerous leaves to enhance better photosynthesis

ADAPTATION OF ANIMALS TO AQUATIC HABITAT

1. Possession of gills (eg fish) and breathing tubes or trumpets (eg mosquito’s larvae) for breathing

2. Possession of swim bladder for buoyancy in water eg fish

3. Possession of streamlined body to facilitate easy movement in water eg fish and frog

4. Possession of fins (eg fish) and webbed feet (eg toad) for movement

5. Possession of sticky under surfaces for attachment to surface of objects eg snails

6. Ability to burrow and remain in moist habitats eg annelids, clams and snails

7. Possession of lateral lines for detecting vibrations eg fish

8. Possession of suckers or hairs for attachment to vegetation to avoid being swept away by water current

9. Possession of nictitating membrane over eyes in fishes and presence of eyelids in toads and frogs

ADAPTATION OF ANIMALS TO TERRESTRIAL HABITAT

1. Possession of powerful limbs for movement eg mammals

2. Possession of lungs for gaseous exchange eg birds, mammals, reptiles and amphibians

3. Possession of hairs as in mammals and feathers as in birds for body temperature regulation

4. Possession of sweat glands fir excretion and cooling eg mammals

5 possession of skin as in mammals and cuticles by insects to protect and prevent drying up and injury

ADAPTATION OF ANIMALS TO ARBOREAL HABITAT

1. Possession of wings for flight eg birds

2. Possession of hollow bones to make them light

3. Possession of bright colors as well as camouflage eg chameleons

4. Possession of powerful limbs, claws and tails for climbing and piercing eg birds, monkeys and baboons

5. Possession of streamlined body for easy flight eg birds

6. Possession of strong muscles and tendons to ease flight eg birds

7. Feeding mainly on grains to provide energy required for flight eg birds

8. Possession of feathers eg birds

9. Possession of oil glands which serves as water proof against wetness of feathers.

ADAPTATION OF PLANTS TO THE AMOUNT OF WATER AVAILABLE

On the basis of water availability, plants can be divided into three groups

Hydrophytes

These are plants that grow inside water or in very wet or moist environments. Such plants have excess water. Most of their adaptive features aim at getting rid of excess water. Some of the adaptations are

1. The floating ones have light bodies eg water lettuce, water hyacinth, water lily, etc

2. Some have small or poor root systems hence they absorb very little amount of water eg water lily and water lettuce. Others do not have root eg bladder wart

3. Many have poorly developed water conducting systems. This prevents the absorption of excess water eg water lettuce

4. Thin cuticles on the surface of their leaves that enables them to easily get rid of excess water

5. Many have well developed air space. These helps to store atmospheric oxygen since the water in which they grow contain less oxygen. The air space also enhances their buoyancy

6. Large hydrophytes like the white mangroves have breathing roots or pneumatophores. These roots stick into the atmosphere from the ground to absorb atmospheric oxygen

7. Many large hydrophytes have stilt roots. These give supports to the plants because the muddy and waterlogged soil on which they grow is often  very soft

Mesophytes

These are plants that grow in environment that are neither too wet nor too dry. They do not have water in excess  yet they do not lack water. The environment in which they grow apart from having abundance of soil water, also have a high relative humidity. Most crops like cassava, yam etc and ornamental plants like hibiscus are examples of mesophytes. They show the following adaptations

1. They have well developed root systems. These enables them to absorb plenty of water

2. Some have broad leaves while others have thin leaves

3. Their body surfaces, especially the leaves are covered in waxy cuticles to reduce water loss by transpiration

 Xerophytes

These are the plants that grow in extremely dry environments like deserts. Water supply in this area is scarce due to little or no rainfall. They have features adapted for water conservation. These are

1. Deep and extensive root systems for absorption of as much water as possible

2. Some have swollen stems and leaves which contains water storage cells dor storing water eg euphorbia aloe, etc

3. The leaves, where present is covered with thick cuticles or wax to reduce water loss

4. Some have reduced leaves eg acacia, other have leaves modified into spines or thorns eg cactus whiles others have no leaves at all or leaves reduced to scales egcasuarina to reduce water loss through transpiration

NB;    In cases where leaves have been replaced by spines and scales, the stem performs the main functions of leaves especially photosynthesis

5. Some have leaves with sunken (lower level) stomata which reduces water loss through transpiration

6. The protoplasm of the cells of most xerophytes can tolerate large amount of water loss and long period of no water without getting killed or damaged. This helps to tolerate long periods of drought

                                                    PR0JECT

1a. whatis meant by adaptation?             

 b. Describe the adaptation of the following to obtaining food;

     i. A named bony fish

     ii. A mosquito larva

     iii.A named parasitic plant

 c. Explain two behavioral adaptations of a named mammal to body temperature regulation

                                                                                                                                                SSCE