SS3 Biology Scheme of Work for Third Term

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.

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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:
  1. Eye color in humans (brown vs. blue).
  2. Blood groups (A, B, AB, O).
  3. Coat color in guinea pigs.
  4. Height in pea plants (tall vs. dwarf).
  5. Ear lobes in humans (attached vs. free).
  6. 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:
  1. Human chromosomes (46 total, 23 pairs).
  2. Fruit fly chromosomes (8 total).
  3. Down syndrome (caused by trisomy 21).
  4. XX and XY combinations in humans.
  5. Polyploid plants like wheat.
  6. 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).
• Causes: Genetic factors, environmental influences.
• Examples:
  1. Skin color.
  2. Fingerprint patterns.
  3. Beak size in birds.
  4. Camouflage in chameleons.
  5. Ear size in elephants.
  6. 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:
  1. Worker termites building tunnels.
  2. Soldiers spraying acid on predators.
  3. Queens laying thousands of eggs.
  4. King and queen starting a new colony.
  5. Workers feeding the young.
  6. Termite colonies aerating the soil.

Week 5: Evolution

• Evolution: Gradual change in species over time.
• Evidence:
  • Fossil records.
  • Comparative anatomy.
  • Molecular biology.
• Examples:
  1. Evolution of horses.
  2. Fossils of Archaeopteryx (link between reptiles and birds).
  3. Adaptive radiation in Darwin’s finches.
  4. Resistance to antibiotics in bacteria.
  5. Whale evolution from land mammals.
  6. 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:
  1. Giraffe neck evolution.
  2. Finches adapting to food sources.
  3. Antibiotic resistance.
  4. Evolution of camouflage in insects.
  5. Fossil evidence of fish to amphibians.
  6. Molecular evidence of common ancestry.