Chapter 9 | The Living Organisms and Their Surroundings | Class 6
Question 1 What is a habitat?Give examples of habitat?
Question 2 How is camel adapted to survive in a desert?
Question 3 How is cactus adapted to survive in a desert?
Question 4 How is fish adapted to survive in water?
Question 5 Write the adaptation in animals which help them to survive in the aquatic habitat like ocean?
Question 6 How is desert plant have adapted to the hot and dry environment?
Question 7 What is meant by adaptation?
Question 8 What is meant by acclimatisation. Give example?
Question 9 Name the biotic and abiotic components of a habitat?
Question 10 What is meant by terrestrial habitat? Give two example of terrestrial habitat?
Question 11 What is meant by aquatic habitat? Give two examples of aquatic habitat?
Question 12 Why speed is important for the survival of animals like deer which live in grassland habitat?
Question 13 How is frog adapted to live in water and on land?
Question 14 Describe the breathing process in sea animals like dolphins and whales?
Question 15 Describe the various adaptations of desert animals?
Question 16 Describe the various ways in which mountain plants is adapted to live in mountain?
Question 17 How is snow leopard adapted to live in cold mountain region having snow all around?
Question 18 How is mountain goat adapted to survive in a mountain region?
Question 19 Name the three types of aquatic plants?
Question 20 Why mountain trees are cone shaped having sloping branches?
The place (or surroundings) where a plant or animal lives is called its habitat.
A habitat provides food, water, air, light, shelter (protection), and a place for breeding to the plants and animals living in it. A habitat provides everything to the organisms which they need to live. Different types of plants and animals live in different habitats.
Some of the examples of habitats are : Forests, Grasslands, Garden, Deserts, Hills, Fields, Soil, Homes, Tree, River, Sea, Pond, Lake, and Sea-shore. A plant or an animal is adapted to survive in its habitat.
All the habitats can be divided into two main groups :-
(1) Terrestrial habitats, and
(2) Aquatic habitats.
A land based habitat is called a terrestrial habitat. The plants and animals which live on
land are said to live in a terrestrial habitat. Examples of terrestrial habitats are Desert, Mountains, Forest, Grassland, Garden, Field, Soil and Homes. A cactus plant and camel live in a dry land called desert. So we can say that cactus and camel live in a terrestrial habitat (called desert).
A water based habitat is called an aquatic habitat. The plants and animals which live in water are said to live in an aquatic habitats. Examples are: Pond, Lake, River, Swamps and Oceans.
The types of habitats vary from organism to organism. The plants grow better and survive longer in a particular habitat to which they are adapted.
Some plants prefer to live in hot and dry areas of land. e.g. cactus plant grows and survives well in the hot and dry areas of desert. This is because cactus is adapted to live on very little water for long periods of time. The habitat of a cactus plant is desert.
Some plants prefer to live in water e.g. Lotus plant grows and lives in the water of a pond. It cannot survive without sufficient water. So, the habitat of lotus plant is a pond. Some of the common plants and their habitats are given below :
|7. Oak Tree||Mountsitains|
|8. Coconut Tree||Sea shore|
The fish is an animal which lives in water. It cannot live without sufficient water. So, the habitat of a fish can be pond, lake, river or sea. On the other hand, camel is an animal which is adapted to survive on very little water for long periods of time. So, the habitat of a camel is the desert. A bird’s habitat is tree. Some of the common animals and their habitats are given below :
|2. Rat||Homes, Fields|
|3 Snake||Forests, Fiels|
|4. Fish||River, Ponds, Lake, Sea|
Plants and animals may share the same habitats, for example, the pond habitat has many types of plants such as: Algae, Hydrilla, Water-lily, Water-hyacinth and some Weeds. The pond habitat has also many types of animals such as: Dragon flies, Kingfishers, Herons, Fish, Frogs, Turtles, Water-spiders, Water-skaters, Snails,Ducks in and around it.
Though a large number of living organisms share the same habitat (say, a pond), but their food habits are different, Due to this, the organisms face less competition for food. This helps in the survival of all the organisms in a habitat.
In a habitat, soil, water, air many other components of physical environment are also present, Thus, a habitat includes both biotic and abiotic components of the environment. The habitat also includes the interactions between the biotic and abiotic components of the environment.
The term “biotic” means “living” So, the living things in a habitat are its biotic components. The living in a habitat are plants, animals and micro-organisms.
The biotic components of a habitat are: Plants, Animals and Micro-organisms. The living things such as plants, animals and micro-organisms in a habitat are known as its biotic components.
The term “abiotic” means “non living”. The various non-living things in a habitat are soil, rocks, air, water, sunlight and temperature.
The abiotic components of a habitat are: Soil, Rocks, Air, Water, Sunlight and Temperature. The various non-living things such as soil, rocks, air, water, sunlight and temperature etc. are called the abiotic components or abiotic factors of the habitat.
1)The soil provides various nutrients such as nitrogen for the growth of plants.
2) Air provides carbon dioxide gas to the plants for making food.
3) Water is also required by the plants to make food.
4) Sunlight provides energy to the plants to make food by the process of photosynthesis.
5) Temperature (or heat) is required for the germination of seeds to grow into new plants.
The abiotic factors such as air ,water sunlight and temperature (or heat) are very important for the growth of plants.
There are many different kinds of habitats having entirely different environmental conditions. Different kinds of plants and animals live in different habitats.
For example: The desert habitat has very little water available in it. The plants and animals which live in desert have developed some specific features in their bodies due to which they can survive in hot and dry conditions present there. Only the plants like cactus and animals like camel can survive easily in the desert because changes have taken place in their body structure over a long period of time which hot desert which have little water only.
In the ocean habitat, the plants and animals are surrounded by saline water (salty water), Most of the plants and animals which live n the ocean use oxygen dissolved in water for breathing. Only the animals like marine fish (sea-fish) and other such creatures can survive in an ocean habitat because changes have occurred in their body structure over long periods of time which help them to survive in the saline water of ocean habitat.
The desert and ocean are very different habitats having very different environments and we find that different kinds of plants and animals live in these two habitats.
A living thing can survive in a particular habitat if its body is suited or adapted to the environment or conditions of that habitat. Plants and animals develop special characteristic or features features in their body in order to survive in their habitat (or surroundings).
The presence of specific feature which enable a plant or an animal to live in a particular habitat is called adaptation.
Adaptation in Camel
The body structure of a camel helps it to survive in desert conditions. Camel is adapted to live in a desert because of its following special features:
1) The camel has long legs which help to keep its body away from the hot sand in the desert.
2) A camel can drink large amount of water (when it is available)and store it in the body.
3)A camel’s body is adapted to save water in the dry desert as follows : A camel passes small amount of urine; its dung is dry and it does not sweat. Since a camel loses very little water from its body, it can live for many days without drinking water.
4) A camel’s hump has ‘fat’ stored in it. In case of emergency, a camel can break down stored fat to obtain water.
5) A camel has large and flat feet which help it to walk easily on soft sand (by preventing it from sinking into soft sand).
Adaptation in Fish
The body structure of a fish helps it to survive inside water. The fish is adapted to live life in water because of its following special features:
1) The head, trunk and tail of a fish merge to form a streamlined shape. The streamlined body shape helps the fish to move through the water easily (because such a shape offers least resistance to motion).
2) The fish has special organs called “gills” which-help it to absorb oxygen-dissolved in water for breathing. A fish can live in water only because it is adapted to breathe in water. A fish cannot live on dry land because it is body shape not adapted to breathe on land.
3) The fish has slippery scales over its body which protect the body from water and also help in easy movement through water.
4) The fish has strong tail for swimming.
5) The fish has flat fins to change direction and keep its body balance in water.
A camel is adapted to the desert environment whereas a fish is adapted to live in water. Adaptation to a habitat does not take place in a short time. Over thousands of years, the abiotic factors of a region change. Those animals (and plants) which cannot adapt to these changes die out and only those which get adapted to the changed environment survive.
SOME TERRESTRIAL HABITATS
Some of the important terrestrial habitats are:
(2) Mountain regions, and
(3) Forests (or Grasslands).
A waterless area of land covered with sand and having little or no vegetation (plants, etc.) is called desert.
The dominant factors in the desert habitat are scarcity (shortage) of water and high temperature.The plants and animals have to protect themselves from excessive loss of water and too much heat.
Adaptation in Desert Animals
In desert, there are animals like desert rats and desert snakes which do not have long legs like camel to keep their body away from hot desert sand. The animals like desert rats and
desert snake survive in the hot desert having lack of water due to the following adaptations:
1)The desert animals survive by living in burrows during the hot daytime.The desert rats and
snakes dig deep burrows in the sand and stay in them during daytime when it is very hot. The burrows stay cool during the day and hence protect these animals from the sun’s heat as well as loss of water from their body. The desert rats and desert snakes come out of the burrows only during cool night in search of food.
2) The desert animals such as desert rats and desert snakes pass out very small amount
of urine and hence conserve water in their body.
Adaptation in Desert Plants
In the hot desert habitat, water is not available to plants in sufficient quantity round the year due to very less rainfall. Moreover, the high temperature in hot desert increases the evaporation of water from the leaves. The plants in desert habitat are well adapted to cope with the shortage of water and high temperature by storing water (when available) and reducing the loss of water.
Some of the adaptations which help desert plants to survive in hot and dry environment of a desert are as follows:
1) The leaves in desert plants are either absent, very small or present in the form of spines or thorns.This helps in reducing the loss of water from the leaves through transpiration. Since desert plants lose very little water through transpiration, they can survive on stored water for a long time.
2)Since the leaves of desert plants are either absent, very small or form spines, the stems of
desert plants are modified to perform the functions of leaves.In desert plants photosynthesis is usually carried out by their green stem.
3) The stems of desert plants are also modified for storing water.The stems of desert plants are also covered with a thick waxy layer (called cuticle) which prevents the loss water from it.
4) Most of the desert plants have long roots which go deep into the soil for absorbing water.
Adaptation in cactus
Cactus is the most common plant found in deserts. The adaptation which help the cactus plants to survive in the hot and dry environment of a desert are given below:
1) Cactus plants have modified their leaves in the form of thin spines (or thorns) to reduce the loss of water through transpiration.
2) The photosynthesis in cactus plants is carried out by the green stem. The green leaf-like structures which we see in a cactus plant is actually its stem.
3)The cactus plants store water in their stems.The stems of a cactus plant is covered with thick waxy layer (called cuticle) which prevents the loss of water from it through evaporation.
4) Cactus plant have long and deep roots to absorb water from a larger area.
A very high hill is called a mountain. The mountain habitats are usually very cold and windy.
Adaptation in Plants to Mountain Habitats
1) There is lot of rain in mountain regions.
2) In the mountain habitat, it is very cold during winter and snowfall may also occur.
3) At very low temperatures in winter, the soil water freezes and hence becomes unavailable to the roots of trees and plants. On the high mountains, it is also more windy.
4)Water evaporates more quickly in windy places due to which the trees on mountains can lose too much water easily through their leaves.
To survive in mountain habitat, the trees should have adaptations to protect themselves from the rain-water, snowfall and loss of too much water. The trees can survive in extremely cold and windy mountain habitats due to the following adaptations:
1) The trees in mountain habitats are usually cone shape having stoping branches.This shape of the mountain trees makes the rain-water and snow to slide off easily without damaging the branches and leaves.
2) Many mountain trees have small, needle-like leaves due to which these leaves lose very
little water in windy conditions.This helps the mountain trees to survive in winter when all
soil water is frozen in the form of ice and not available to their roots.
3) The needle-like leaves have a thick waxy layer (or cuticle) to reduce the loss of water through transpiration and.to.protect them from damage by rain and snow.
4)The broad-leaved trees found on mountains shed their leaves before the onset of winter. This prevents such trees from losing-water from their leaves and helps in their survival during winter when all the water in soil is frozen and hence not available to the roots.
Adaptation in Animals to Mountain Habitats
The adaptation in some animals such as yak, mountain goat and snow leopard which live in mountain regions are:
(1) Adaptation in Yak
It is covered with long silky hair to protect them from cold by keeping them warm.
(2) Adaptation in Mountain Goat
Mountain goat has to live in the cold climate of mountains as well as to run up the rocky slopes of the mountains for grazing. A mountain goat is adapted to cold and rocky environment of a mountain habitat as follows:
1)The mountain goat has long hair to protect it from cold and keep it warm.
2)The mountain goat has strong hooves for running up the rocky slopes of mountains for grazing (The hard and rough feet of an animal are called hooves)
Adaptation in Snow Leopard
The snow leopard lives in mountains where snow is present.The snow leopard is adapted to live in extremely cold places having snow as follow:
1) The snow leopard has thick fur on its body. This fur protects the them from cold and keeps it warm. The snow leopard has also fur on its feet and toes. This protects its feet from cold when it walks on the snow.
2) The snow leopard has a thick layer of fat beneath its skin for insulation” to protect it from cold.
3)The snow leopard has a rounded body and small ears to keep the body surface area to a minimum. This reduces the heat loss from the body of snow leopard.
4) The snow leopard has big feet to spread the weight on snow and prevent it sinking into soft snow.
FORESTS (OR GRASSLANDS)
A large area of land covered mainly with trees and plants is called a forest. And a large area of grass covered land used for grazing is called grassland.
There are few trees or places for animals to hide in grassland habitats. Due to this, speed is important for the animals which live in grassland habitats(so that they can run away from their enemies).
Adaptation in Lion
The lion is a carnivorous animal which eats only the meat (or flesh) of other animals . The lion lives in a forest habitat. The lion is adapted to the forest habitat in the following ways:
1) The lion is a strong, fast and agile animal which can hunt and kill its prey like deer.
2)The lion has long, strong and sharp claws in its front legs to catch its prey. The lion can withdraw (pull in) the claws inside the toes so that they do not become worn out and blunt.
3) The lion has eyes in front of its head which enable it to have a correct idea of the location of its prey. This helps it in catching the prey.
4. The lion is light brown in colour. The light brown colour helps the lion to hide in dry grassland (without being noticed) when it hunts for prey.
Adaptation in Deer
The deer is a herbivorous animal which eats only the plant material as food. Deer is another animal which lives in forest habitat. The deer is adapted to the forest habitat in the following ways:
1) The deer has eyes on the sides of its head which enable it to see in all directions at the same time. The all round vision of deer helps it to see animals like lion (which kill it), in all the area around it.
2) The deer has big ears for good hearing. The big ears help the deer to hear the movements of predators (like lion) very easily.
3)The deer is fast and agile animal. The speed of deer helps it to run away from the predators which try to catch it.
4) The deer has brown colour. The brown colour of deer helps it to hide in dry grasslands without being noticed by lion, etc.
5. The deer has strong teeth for chewing hard plant stems of the forest.
SOME AQUATIC HABITATS
The habitats having water all around are called aquatic habitats. The important aquatic habitats are :Oceans,Ponds, Lakes and Rivers.
Ocean water contains a lot of salts dissolved in it, so ocean water is very salty. Ocean is not a fresh water habitats.
On the other hand ponds, lakes and rivers are called fresh-water habitat.
A very large area of sea is called ocean.
The adaptations in animals living in water are about their movement in water for breathing.
Some of the adaptations in animals living in the aquatic habitats like ocean (or sea) are as follows:
1) Many sea-animals have streamlined bodies to help them move in sea-water easily. For
example: The fish living living in the sea habitat have streamlined body shapes.
Some sea-animals like squids and octopus do not have streamlined body shape. But when squids and octopus move in sea-water, they make their body shape streamlined.Such animals stay deeper in the ocean near the sea-bed and catch any prey that moves towards them.The streamlined shape of sea animals is an adaptation for swimming in water.
2 Most of the sea-animals have gills which enable them to use oxygen dissolved in water for breathing.So, the presence of gills in sea-animals is an adaptation for breathing inside the water.Dolphins and whales breathe in air through nostrils (called blowholes) which are located on the upper parts of their heads. Dolphins and whales breathe in air through blowholes when they swim near the surface of water. After breathing in air, they close the blowholes with flaps and dive into the sea. Dolphins and whales can stay inside water for long time without breathing. The presence of nostrils in dolphins and whales is an adaptation for breathing.
2. PONDS, LAKES AND RIVERS
The plants which grow in water are called aquatic plants.
The three types of aquatic plants:
1) Some aquatic plants which float on the surface of water are water.
For example: water-lettuce and water hyacinth.
(b)Some aquatic plants are partly submerged in water .
1)The roots of partly submerged plants are fixed in the soil below water at the bottom of pond, lake or river.
2) The stems of such plants grow up to the surface of water while the leaves and flowers float on the surface of water.
The two examples of aquatic plants which are partly submerged in water are water lily and lotus.
(3) Some aquatic plants are completely submerged in water
The roots of submerged plants are also fixed in the soil below water at the bottom of pond, lake or river. All the parts of such plants (including stem, branches and leaves) grow under water.
The two examples of completely submerged aquatic plants are Hydrilla and Vallisneria.
Adaptations in Aquatic Plants (or Water Plants)
Some of the adaptations in aquatic plants are given below:
1. The aquatic plants have very short and small roots whose main function is to hold the plant in place. All the parts of an aquatic plant are surrounded by water, so an aquatic plant can absorb water and dissolved minerals directly from the surface of their stems, branches and leaves. Since the aquatic plants do not have to depend on their roots to obtain water and dissolved minerals, their roots are very short and small.
2. The stems of aquatic plants are soft, hollow and light, having large spaces filled with air. The aquatic plants do not need strong stems because the surrounding water of a pond, lakes ,river keeps them up.
3.The submerged aquatic plants have narrow and thin ribbon-like leaves which bend in the flowing water of rivers and streams and hence do not obstruct the flow of water. In some
plants, the leaves are highly divided so that water can easily flow through them without damaging them. The thin leaves of submerged plants also allow the minerals to pass into them easily. The floating leaves of partly submerged plants are quite broad but flexible. The leaves of floating plants are, however, similar
to those of land plants.
Animals Adapted to Live in Water and on Land
The animals like frog have ponds as their habitat.Frogs are found in shady, damp conditions near ponds. Frogs can live inside water as well as on land, near the pond. Frogs spend most of their time on land but come back to water to lay their eggs. Frogs are adapted to
live life in water as well as on land in the following ways:
1)Frogs have webbed back feet which help them to swim in water (webbed feet are formed from thin skin between toes and work like paddles for swimming). This adaptation helps the frogs to live life in water.
2 Frogs have strong back legs for hopping (jumping) and catching their prey. This adaptation helps the frogs to live life on land.
Adaptations are very, very slow changes which take place in the bodies of organisms over thousands of years There are, however, some changes which can occur in organisms over a short period of time to help them to adjust to some sudden changes in their environment.
For example : If we live in the plains and suddenly go to a high mountain region, we may experience difficulty in breathing for a few days. This is because the air is very thin at the “high altitude” on the mountain due to which we have to breathe faster so as to obtain sufficient oxygen. After some days however, small changes occur in our body due to which our body adjusts to the new environment of thin air on mountain.We say that our body has acclimatised (or got used) to the mountain environment.
The process of becoming accustomed to a different environment (such as high altitude of mountains) over short periods is called acclimatisation. The changes which take place in the body of an organism during acclimatisation are temporary and can be reversed. On the other hand, the changes which take place during adaptation are permanent and cannot be reversed.