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The ability of living organisms to adjust themselves to their surroundings is called adaptation. Adaptations are the changes in structure or behaviour of an organism that will allow the organism to survive in that habitat.

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Habitat is the immediate surroundings of an organism. It is the place that is natural for the life and growth of the organism. 

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Characteristics: 1 Mark each
Aquatic animals have gills to breathe under water.
Aquatic animals have streamlined body for effective navigation in water.

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Types of forests: 1 Mark each.
There are three types of forests -  tropical forests, temperate forests and boreal forests.
Tropical forests, also known as rainforests, are the forests which exist between the equator and the two tropics. The temperature in these forests is moderate (20^oC to 34^oC). They receive rainfall throughout the year. Different types of flora and fauna exist in these forests.

Temperate forests exist in Northeast Asia, North America, and Central Europe. Temperature ranges between -30^oC to 30^oC. Rainfall is received throughout the year. Summer season is demarcated from the winter season. The trees that grow here are deciduous.
Boreal forests, also known as Taiga forests, are scattered over many places including China, Canada, Russia, Northern Japan etc. They exist in cold regions ( -50^oC to 30^oC) and have coniferous trees.

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Types of habitat: 1 Mark each.
There are three types of aquatic habitat - Freshwater, marine, and coastal.
1. Freshwater habitat: These habitats consist of the water bodies filled with fresh water, like rivers, lakes, ponds, streams etc.The water has very less amount of salts dissolved in it.
2. Marine habitat: Aquatic habitats where the water has a high content of salt are known as marine habitats. Oceans and seas are examples of marine habitats. The marine habitat has a lot more organisms in it than the freshwater habitats. Organisms like corals, shelled animals, sponges, jellyfish, sharks and many others are found in this habitat.
3. Coastal habitat: This is the habitat formed in the place where land meets the sea. Estuaries are formed in these areas, and trees like mangroves can be found here.

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Element: 1 Mark each.
$\begin{array}{ccc}\text{S.No}& \text{Element}& \text{Feature}\\ 1& \text{Bacteria}& \text{Biotic}\\ 2& \text{Dog}& \text{Biotic}\\ 3& \text{Humidity}& \text{Abiotic}\\ 4& \text{Temperature}& \text{Abiotic}\\ 5& \text{Water}& \text{Abiotic}\end{array}$

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Types: 1 Mark
Definition: 1 Mark
The two main types of habitats are terrestrial and aquatic habitat.
Terrestrial habitat is any habitat that is found on land, like forests, grasslands, deserts, and shorelines.
Aquatic habitat is a habitat that is wholly or partially submerged in water. Most animals that live in an aquatic habitat cannot go on land.

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Adaptations: 1 Mark each
The three adaptive features of a desert plant are:

1) Leaves are reduced to spines to reduce the surface area of the leaf.

2) Leaves have a thin waxy coating to prevent loss of water through transpiration.

3) Roots are thin and extensive to search for moisture in the soil efficiently.

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Habitats: 1 Mark each 

$\begin{array}{ccc}\text{S.No}& \text{Animal}& \text{Habitat}\\ 1& \text{Frogs}& \text{Terrestrial and aquatic}\\ 2& \text{Dogs}& \text{Terrestrial}\\ 3& \text{Corals}& \text{Aquatic}\\ 4& \text{Dolphins}& \text{Aquatic}\\ 5& \text{Monkeys}& \text{Terrestrial}\end{array}$

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Characteristic + explanation: 1 Mark each
All living things exhibit certain characteristics of life that non-living things don't. For example, 
Any 5:
1. Living things require food
Living things require food to survive and grow. Food makes the body grow faster and gives energy to the body to help it perform the life activities.
2. Living things exhibit growth
All living things take in food to obtain energy. That energy is used for growth. Organisms increase in height, weight etc. to exhibit growth. Living organisms have different stages of growth in their life.
3. Living things perform respiration
Respiration is the process of breathing in oxygen and giving out carbon dioxide. Respiration takes place in every cell and is called as cellular respiration. Oxygen is necessary to break food and produce energy from it. Different animals possess different organs for respiration.
4. Living things excrete
The process of eliminating wastes from the body is called excretion. Plants eliminate harmful waste substances in the form of secretions such as resins and gums. Animals excrete their wastes in the form of ammonia or urea or uric acid, carbon dioxide and certain salts.
5. Living things move
All living organisms move at some point or another. Even plants, which are stationary, exhibit movement in the form of roots growing towards the earth or the stems bending towards sunlight.
6. Living things respond to stimuli
Stimulus is the change in the immediate environment of a living organism. Every living thing responds in some way or the other to stimuli. Plants respond to environmental stimuli like sunlight by growing their stems towards it.
7. Living things Reproduce
All living things reproduce. Some animals lay eggs, while others reproduce by giving birth to young ones.
8. Living things Die
All living things must die one day or the other. As an organism grows, it undergoes many changes during its lifetime. Finally, it dies after its lifetime is over.