TERM – 2ND TERM
WEEK EIGHT
Class: Senior Secondary School 1
Age: 15 years
Duration: 40 minutes of 5 periods each
Date:
Subject: Biology
Topic: ADAPTATION
SPECIFIC OBJECTIVES: At the end of the lesson, pupils should be able to
- Explains the meaning of adaptation.
- Discuss the effects of availability of water on adaptive modification
iii. Describe the structural Adaptation of a fish
- Describe the structural Adaptation of a tadpole
INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers,
demonstration, videos from source
INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, picture
INSTRUCTIONAL PROCEDURES
PERIOD 1-2
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PRESENTATION
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TEACHER’S ACTIVITY
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STUDENT’S
ACTIVITY
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STEP 1
INTRODUCTION
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The teacher introduces adaptation and explain the effects of availability of water on adaptive modification
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Students pay
attention
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STEP 2
EXPLANATION
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Teacher guide students to draw a fish and discuss it's structural Adaptation
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Students pay
attention and
participate
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STEP 3
DEMONSTRATIO
N
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Teacher guide students to draw a tadpole and discuss it's structural Adaptation
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Students pay
attention and
participate
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STEP 4
NOTE TAKING
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The teacher writes a summarized
note on the board
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The students
copy the note in
their books
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NOTE
ADAPTATION
Adaptation refers to the process of adjusting to new conditions or modifying oneself to better fit a different environment, situation, or circumstance. It can apply to various contexts, such as biology, literature, or technology.
Effects of availability of water on adaptive modification
The availability of water significantly influences adaptive modifications in organisms and ecosystems:
- Physiological Changes: Organisms may undergo physiological adaptations to cope with varying water availability. This includes adjustments in metabolic processes, osmoregulation, and water retention mechanisms.
- Structural Modifications: Plants can undergo structural changes such as altering leaf morphology, developing specialized tissues for water storage, or modifying root systems based on water availability. In animals, structural adaptations like efficient water-conserving excretory systems may evolve.
- Behavioral Adjustments: The availability of water often prompts behavioral adaptations. Species may change their feeding habits, migration patterns, or daily activities in response to water scarcity or abundance.
- Reproductive Strategies: Water availability plays a crucial role in reproductive adaptations. Species may adjust their breeding seasons, mating behaviors, and offspring survival strategies based on the timing and availability of water resources.
- Ecosystem Dynamics: Changes in water availability can lead to modifications in ecosystem structures and functions. Shifts in species composition, trophic interactions, and energy flow within ecosystems may occur as a result of water-related adaptations.
Structural Adaptation of fish
Fish exhibit various structural adaptations that enhance their survival in aquatic environments:
- Body Shape: Fish have streamlined bodies that reduce drag in water, allowing for efficient swimming. Different species may have body shapes suited to their specific habitats, such as fusiform (torpedo-shaped) for fast swimming or laterally compressed for maneuverability in tight spaces.
- Fins: Fins are specialized structures for movement and stability. Dorsal fins provide stability, while pectoral fins aid in steering and stopping. Caudal (tail) fins vary in shape and size, contributing to different swimming styles, from powerful propulsion to precise maneuvering.
- Gills: Gills are respiratory organs that extract oxygen from water. Fish have gill arches with filaments that provide a large surface area for efficient oxygen exchange. Some species have adapted gill structures to thrive in specific water conditions, like those with low oxygen levels.
- Scales:.Fish scales protect the skin from injuries and pathogens. They also reduce friction, aiding in streamlined movement. The type of scales can vary, such as cycloid or ctenoid, providing flexibility and protection.
- Lateral Line System: The lateral line is a sensory system consisting of small, fluid-filled canals along the fish's body. It detects changes in water pressure, helping fish navigate, locate prey, and avoid obstacles.
Structural Adaptation of tadpole
Tadpoles undergo structural adaptations during metamorphosis, transforming into frogs. This process involves the development of hind limbs, reabsorption of the tail, changes in respiratory structures (gills to lungs), and modifications in the digestive system to accommodate a shift from herbivorous to carnivorous diet.
EVALUATION: 1. Define adaptation
- Describe how the availability of water affect adaptive modification.
- Discuss the structural Adaptation of a fish
CLASSWORK: As in evaluation
CONCLUSION: The teacher commends the students positively
