Adaptations are special features that allow a plant or animal to live in a particular place or habitat. The ability of living organisms to adjust themselves to the surroundings is called as adaptation. Adaptations are the changes in structure or behaviour of an organism that will allow the organism to survive in that habitat.
Plants and animals make some natural adjustments in some features to fit themselves into their environment. Different living organisms adapt themselves to their habitats in different ways. Adaptations can be brought about by changes in the body, changes in the behaviour and changes in location.
Adaptation of animals in aquatic habitat
Animals which live in aquatic habitat are adapted by structural modification of the structures of their body and also by developing the new structures. Aquatic animals are adapted by modifying the structures present in their bodies which are known as the adaptational structures or adaptational features. The adaptational features of aquatic animals are as follows:
1- Body is stream-lined in shape which helps to minimize water resistance which makes them easy to live in water.
2-Respiratory organs are the gills in perfectly aquatic forms like fishes but in the air breathing forms nostrils are located near the top f the head to enable them t go to surface frequently to inhale air.
3-Locomotary organs are developed as the fins to swim in water easily. There are different types of fins like dorsal fin, ventral fin, caudal fin, pectoral fins and pelvic fins. All the fins help in swimming but the caudal fin helps them to balance the body in water. Sme aquatic forms like amphibians have the thin fold f skin in between the digits f the hind limbs which are called web. Web helps to increase the surface area for swimming. Aquatic animals like turtles have fin like organs called paddles for swimming and whales have the flippers as the swimming organ.
4- Body is covered by scales which make the body soft and slippery so as to escape from the enemies and also helps them to prtect the internal soft organs of the body.
5- Some fishes have got the hydrostatic organ called air bladder for adjusting them in the different depths of water according to their need by increasing the amount of gas or by decreasing the amount of gas in side the air bladder.
ADAPTATION OF AQUATIC PLANTS
Plant Adaptations
Plants have adaptations to help them survive (live and grow) in different areas. Adaptations are special features that allow a plant or animal to live in a particular place or habitat. These adaptations might make it very difficult for the plant to survive in a different place. This explains why certain plants are found in one area, but not in another. For example, you wouldn’t see a cactus living in the Arctic. Nor would you see lots of really tall trees living in grasslands.
Plant Adaptations in Water
- underwater leaves and stems are flexible to move with water currents
- some plants have air spaces in their stems to help hold the plant up in the water
- submerged plants lack strong water transport system (in stems); instead water, nutrients, and dissolved gases are absorbed through the leaves directly from the water.
- roots and root hairs reduced or absent; roots only needed for anchorage, not for absorption of nutrients and water
- some plants have leaves that float atop the water, exposing themselves to the sunlight
- in floating plants chlorophyll is restricted to upper surface of leaves (part that the sunlight will hit) and the upper surface is waxy to repel water
- Some plants produce seeds that can float
| In floating plants, chlorophyll is restricted to the upper surface. Note the green color on the top of the leaves and the reddish underside of the overturned leaf. | Aquatic plants must be flexible to withstand the pressures of moving water. |
The Desert
The desert is very dry and often hot. Annual rainfall averages less than 10 inches per year, and that rain often comes all at the same time. The rest of the year is very dry. There is a lot of direct sunlight shining on the plants. The soil is often sandy or rocky and unable to hold much water. Winds are often strong, and dry out plants. Plants are exposed to extreme temperatures and drought conditions. Plants must cope with extensive water loss.
Desert Plant Adaptations
- Some plants, called succulents, store water in their stems or leaves;
- Some plants have no leaves or small seasonal leaves that only grow after it rains. The lack of leaves helps reduce water loss during photosynthesis. Leafless plants conduct photosynthesis in their green stems.
- Long root systems spread out wide or go deep into the ground to absorb water;
- Some plants have a short life cycle, germinating in response to rain, growing, flowering, and dying within one year. These plants can evade drought.
- Leaves with hair help shade the plant, reducing water loss. Other plants have leaves that turn throughout the day to expose a minimum surface area to the heat.
- Spines to discourage animals from eating plants for water;
- Waxy coating on stems and leaves help reduce water loss.
- Flowers that open at night lure pollinators who are more likely to be active during the cooler night.
- Slower growing requires less energy. The plants don’t have to make as much food and therefore do not lose as much water.
| This cactus displays several desert adaptations: it has spines rather than leaves and it stores water in its stem. | This cactus displays light-colored hair that helps shade the plant. | This plant has a waxy coating on its leaves. |
The Temperate Grasslands
The temperate grasslands, also called prairie, feature hot summers and cold winters. Rainfall is uncertain and drought is common. The temperate grasslands usually receive about 10 to 30 inches of precipitation per year. The soil is extremely rich in organic material due to the fact that the above-ground portions of grasses die off annually, enriching the soil. The area is well-suited to agriculture, and few original prairies survive today.
Temperate Grassland (Prairie) Plant Adaptations
- During a fire, while above-ground portions of grasses may perish, the root portions survive to sprout again
- Some prairie trees have thick bark to resist fire
- Prairie shrubs readily resprout after fire
- Roots of prairie grasses extend deep into the ground to absorb as much moisture as they can
- Extensive root systems prevent grazing animals from pulling roots out of the ground
- Prairie grasses have narrow leaves which lose less water than broad leaves
- Grasses grow from near their base, not from tip, thus are not permanently damaged from grazing animals or fire
- Many grasses take advantage of exposed, windy conditions and are wind pollinated
- Soft stems enable prairie grasses to bend in the wind
| Soft stems enable prairie grasses to bend in the wind. Narrow leaves minimize water loss. | Many grasses are wind pollinated and are well-suited to the exposed, windy conditions of the grasslands. |
ADAPTATION OF FROGS
All animals adapt to survive in the wild, and frogs are no exception. Here is a list of the top ten physical adaptations that enable frogs to thrive in wetlands.
- Legs: Frogs have very powerful back legs and webbed feet that help them swim and jump.
Some frogs even use their legs to dig, or burrow underground for hibernating. Certain frogs can jump up to 20 times their own body length in a single bound.
- Skin: Frogs can breathe though their skin so they can stay underwater as long as they want.
- Skin: Frogs don’t drink water through their mouths at all, instead they soak it into their bodies through their skin.
- Skin: Frog skin is often camouflaged to hide from predators. Some frogs can change the colour of their skin depending on its surroundings.
- Skin: Some frogs secrete poison through their skin. Many of the more easily visible, brightly colored tropical frogs are colored in this way to warn predators that they are poisonous.
- Croaks: Frogs attract each other for mating with their croak. Each frog species has a distinct croak. They have vocal sacs, which fill with air, and can amplify the sound up to a mile away.
- Tongue: When a frog spots a tasty meal, it flicks out its long, sticky tongue. The tongue wraps around the meal/insect and pulls it back into the frog’s mouth. Unlike humans, a frog’s tongue is not attached to the back of its mouth. Instead it is attached to the front, enabling the frog to stick its tongue out much further.
- Teeth: Frogs do have teeth, but they are small and not good for chewing. Instead, frogs use their teeth to hold their prey in their mouths until they are ready to swallow.
- Eyes: Frogs swallow using their eyes. Its eyes retract into its head and push the food down its throat. Frog’ eyes are on top of their heads so when they swim close to the surface of the water, only their eyes are exposed. This way, they can quickly spot danger before danger spots them.
- Eyes: Frogs can see forwards, sideways and upwards all at the same time and never close their eyes, even when they sleep. They even have a third eyelid which is see-through and protects the frog’s sensitive eyes when it is under water.
Acclimatisation:
The ability of an organism to make small adjustments or changes in the body in a short period of time to adjust itself to the surrounding atmosphere is called acclimatisation. People who visit mountain ranges suffer from altitude sickness due to poor oxygen content in the atmosphere at such heights. Their body gets adjusted or acclimatised to changes in the surroundings.
Components of a habitat
The components in a habitat are broadly classified into two types, namely biotic and abiotic components. Biotic components interact with abiotic components to obtain all the necessary conditions.
Biotic components include all the livings organisms in a habitat, i.e. plants, animals and microorganisms.
Abiotic components include all the non-living things in a habitat, i.e. air, soil, water, sunlight and temperature. The favourable conditions for survival of living organisms are provided by abiotic components.
- a) Air: Air is essential for all the living organisms on earth. Plants and animals take in oxygen from the air during respiration. Plants take in carbon dioxide during the process of photosynthesis. Air also provides nitrogen which is fixed to the plants for utilisation. Air is required by organisms to cool their body. Winds help in generating energy. Winds also help in carrying the seeds for distant places.b) Soil: Soil is the topmost layer of the earth. Soil is rich in minerals and microorganisms which help in different ways for plant growth. Soil also possess certain spaces which lodge water particles. This water lodged in the spaces is used by plants by the process of absorption.
c) Water: Three-fourths of our earth is covered with water. Water is essential for life. Water forms a medium for many metabolic reactions taking place inside the body. Water can be fresh water or marine water. Animals living in water are called as aquatic organisms. Plants specially living in water are called as hydrophytes. Humidity and rain are also the forms of water which help the living organisms.
d) Sunlight: Sun is the ultimate source of energy for all the living organisms on earth. Plants depend on sunlight for synthesising their food by the process of photosynthesis. Animals depend on plants for their food i.e. indirectly they depend on sunlight.
e) Temperature:Temperature at a place depends on the sunlight available at the particular place. Temperature also influences the humidity of that particular place. Areas may be too hot, moderate or too cool. Some animals hibernate during cool winter and some of them aestivate during hot summer.
EVALUATION
1.The two factors that affect living organisms are a.Abiotic and amniotic factors b.Abiotic and Non-abiotic factors c.Abiotic abd Biotic factors d.Biotic and biological factors.
2,.Features that help organism to survive in a particular habitat is called ——–a.Homes b.Adaptation c.Favourites d.Permanent home.
Assignment
Define the following
1.Biotic factors ii.Abiotic factors
2.Give Examples
See also