Below is a detailed scheme of work for the SS2 Biology third term. It includes the topics for each week, along with comprehensive explanations and examples to help students easily understand the concepts.
| Week(s) | Topic(s) | Content |
|---|---|---|
| Week 1 | Heredity (Genetics) | Definition of heredity, basic principles of genetics, Mendel’s experiments, laws of inheritance, and examples of inherited traits in humans and animals. |
| Week 2 | Chromosomes | Structure and function of chromosomes, types (autosomes and sex chromosomes), and their roles in heredity, with examples such as human chromosome pairs. |
| Week 3 | Variation and Evolution | Types of variation (continuous and discontinuous), causes of variation, examples of physical and genetic variations, and their role in evolution. |
| Week 4 | Different Castes of Termites and Their Roles | Explanation of termite social structure (queen, king, workers, soldiers), their roles in a colony, and examples of ecological importance. |
| Week 5 | Evolution | Definition, evidence of evolution (fossil records, comparative anatomy), and examples of evolutionary changes in organisms. |
| Week 6 | Theories of Evolution | Overview of major theories (Darwinism, Lamarckism, Modern Synthesis), their key principles, and examples of species adaptation. |
| Week 7 | Process of Development of Zygote in Flowering Plants (Continuation) | Fertilization process in plants, development stages of a zygote, and examples such as maize and pea plants. |
| Week 8 | The Fruit | Definition, types of fruits (simple, aggregate, multiple), structure of a fruit, and examples like mango, apple, and guava. |
| Week 9 | The Fruit (Continuation) | Further analysis of fruit dispersal mechanisms, adaptations for dispersal, and more examples like dandelions and coconuts. |
| Week 10 | Adaptation for Survival | Explanation of structural, physiological, and behavioral adaptations in plants and animals, with examples such as desert plants and Arctic foxes. |
| Week 11 | Revision | Comprehensive review of the term’s work and mock assessments. |
| Week 12 | Examination | Term-end evaluation to assess students’ understanding and retention. |
Detailed Explanations of Each Topic
Week 1: Heredity (Genetics)
- Heredity is the transmission of genetic traits from parents to offspring.
- Basic principles of genetics include dominant and recessive traits.
- Mendel’s experiments: Gregor Mendel used pea plants to establish the laws of inheritance.
- Examples:
- Eye color in humans (brown vs. blue).
- Blood groups (A, B, AB, O).
- Coat color in guinea pigs.
- Height in pea plants (tall vs. dwarf).
- Ear lobes in humans (attached vs. free).
- Fur color in cats (black vs. white).
Week 2: Chromosomes
- Chromosomes are thread-like structures made of DNA and proteins found in the nucleus.
- Functions:
- Carry genetic information.
- Control cell activities.
- Types:
- Autosomes (non-sex chromosomes).
- Sex chromosomes (X and Y in humans).
- Examples:
- Human chromosomes (46 total, 23 pairs).
- Fruit fly chromosomes (8 total).
- Down syndrome (caused by trisomy 21).
- XX and XY combinations in humans.
- Polyploid plants like wheat.
- Chromosome mutations in cancer.
Week 3: Variation and Evolution
- Variation: Differences between individuals of the same species.
- Types:
- Continuous (e.g., height, weight).
- Discontinuous (e.g., blood groups).
- Types:
- Causes: Genetic factors, environmental influences.
- Examples:
- Skin color.
- Fingerprint patterns.
- Beak size in birds.
- Camouflage in chameleons.
- Ear size in elephants.
- Melanin levels in skin.
Week 4: Different Castes of Termites and Their Roles
- Caste system in termites:
- Queen: Reproduction.
- King: Mates with the queen.
- Workers: Build and maintain the nest.
- Soldiers: Defend the colony.
- Examples:
- Worker termites building tunnels.
- Soldiers spraying acid on predators.
- Queens laying thousands of eggs.
- King and queen starting a new colony.
- Workers feeding the young.
- Termite colonies aerating the soil.
Week 5: Evolution
- Evolution: Gradual change in species over time.
- Evidence:
- Fossil records.
- Comparative anatomy.
- Molecular biology.
- Examples:
- Evolution of horses.
- Fossils of Archaeopteryx (link between reptiles and birds).
- Adaptive radiation in Darwin’s finches.
- Resistance to antibiotics in bacteria.
- Whale evolution from land mammals.
- Peppered moth during the industrial revolution.
Week 6: Theories of Evolution
- Key theories:
- Darwinism: Survival of the fittest.
- Lamarckism: Inheritance of acquired traits.
- Modern Synthesis: Genetic mutations drive evolution.
- Examples:
- Giraffe neck evolution.
- Finches adapting to food sources.
- Antibiotic resistance.
- Evolution of camouflage in insects.
- Fossil evidence of fish to amphibians.
- Molecular evidence of common ancestry.
