Lesson Notes By Weeks and Term - Junior Secondary School 2

FIRST TERM

SUBJECT: BASIC SCIENCE

CLASS: JSS 2

REFERENCE

• Precious seed BASIC SCIENCE FOR JUNIOR SECONDARY SCHOOLS BOOK 2

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WEEK TWO

TOPIC: ADAPTATIONS���

CONTENT

• Adaptation of plants to an Aquatic Habitat
• Adaptation of Animals to Aquatic Habitat
• Adaptation of Plants to Terrestrials Habitats
• Adaptation of Animals to a Terrestrial Habitat

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Adaptation� is the ability of all living things to develop structural and behavioral features that make them to survive in their habitats. The features that make them to survive in their habitat are termed Adaptive Features. Plants and animals live in places that suit them .Their bodies are structured in a way that they can survive in their habitat. The duck has webbed feet which helps it to swim. The fish possesses gills and fins for movement.

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The lizard has specialized legs for climbing walls or trees. Also man has five digit fingers to grasp or hold things.

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Adaptation of plants to an Aquatic Habitat

Aquatic plants include the following: sea-weeds, spirogyra, water lettuce, water lilies, brown algae, etc. These plants are termed Hydrophytes. They possess the following features:

1. i)� They have chloroplast for photosynthesis.
2. ii)�Some plants possess mucilage to prevent desiccation e.g. spirogyra.

����iii) They have holdfast for attachment�

1. iv) Some plants rootlets to breathe in water
2. v) Some plants have boat-like leaves to float on water surface e.g. water lettuces
3. vi) They have hair spaces in their tissues to float on water surface

��vii) Some plants have roots to the bottom of the water.

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Adaptation of Animals to Aquatic Habitat

Aquatic animals possess the following adaptive features to live in water:

1. They have fins to move in the water�
2. They possess streamlined shape to move in water
3. �They have gills to breathe in water
4. Some animals home lateral lines to detect vibrations in water
5. Some animals possess exoskeleton to prevent dessication
6. Some of the animals borrow into the mud to protect themselves
7. Some animals have long legs to crawl on water

Adaptation of Plants to Terrestrials Habitats

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1. To a forest Habitat

1. They have thin bark for their transportation
2. They have large leaves or many leaves to increase their water loss or transportations.
3. They have chloroplasts for photosynthesis.

EVALUATION

1. Define adaptation

1. State two adaptation of animals to aquatic habitat
2. To a Desert Habitat

1. They possess thick bark to reduce their water loss(i.e. transpiration)
2. They have few or reduced leaves to reduce water loss or conserve their water
3. They have deep roots to search for water in the soil.
4. Some possess thick or succulent leaves and stem to reduce water loss e.g. Cactus.
5. They shed leaves during the dry season to protect them against water loss.

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Adaptation of Animals to a Terrestrial Habitat

Mammals adapt to the terrestrial habitat in the following ways:

1. They have a hairy skin to keep their body warm.
2. They have sweat gland to regulate the body temperature

1. They have lungs for breathing.
2. They have ear pinnae to locate direction of the sound and escape from dangers.

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EVALUATION

1. Define the term habitat.
2. What do you understand by terrestrial habitat?
3. Give three examples of marine animals.

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GENERAL EVALUATION

1. Define the term habitat.
2. What do you understand by terrestrial habitat?
3. Give three examples of marine animals.
4. List� ten animals and their� adaptive features.�
5. State the relevance of these features to these animals.

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WEEKEND ASSIGNMENT

1. Marine habitat are called----

1. Terrestrial habitat B. Fresh habitat C. Aquatic habitat D. Salt water habitat

1. Terrestrial habitat are referred to as------A. floor habitat B. land habitat C. sea habitat D. oceanic habitat.
2. Fish possesses gills and fins for ----A. jumping B. movement C. flying D. eating.
3. Duck has ---- for swimming. A. webbed feet B. finger C. flying D. nest.
4. A -------� is a type of place where plants and animals� live.

1. Habitat B. home C. trees D. aquatic

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THEORY

1. List� three animals and their� adaptive features.�
2. State the relevance of these features to these animals.

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READIND ASSIGNMENT

Precious seed BASIC SCIENCE FOR JUNIOR SECONDARY SCHOOLS BOOK 2 page 28-33