Section A: Understanding Genetics
- Define the term 'Gene'. Where is it located?
- Differentiate between Genotype and Phenotype with an example.
- What do you refer to as 'Dominant' and 'Recessive' traits?
- Define Heterozygous and Homozygous conditions with symbols.
- What is a 'Trait'? Give two examples of human traits.
- How is the genetic contribution of male and female parents equal in the offspring? (23 + 23
chromosomes).
- Variation is lesser in asexual reproduction. Why?
- State Mendel's Law of Dominance.
- What is the Law of Segregation (Purity of Gametes)?
Section B: Monohybrid Cross
- Give reason: Why did Mendel select the Garden Pea for his experiments? (3 points).
- If a pure Tall plant (TT) is crossed with a pure Dwarf plant (tt), what will be the height of the
plants in F1 generation?
- What happens when F1 plants (Tt) are self-pollinated? Show with a Punnett square.
- What is the Phenotypic and Genotypic ratio of a standard monohybrid cross?
- If 100 plants are produced in F2 generation of a monohybrid cross, how many are expected to be
dwarf? (25).
- Why do we not see any dwarf plants in the F1 generation?
Section C: Sex Determination
- What are Autosomes? How many pairs are there in humans?
- Differentiate between X and Y chromosomes. (Size, gene content - optional, basic diff is sex
determination).
- "The sex of the child is determined by the father." Justify this statement with a flowchart.
- Why is the probability of having a male child 50%?
- What would happen if the sperm carries an X chromosome?
Section D: Variation
- Why is variation important for a species?
- How does sexual reproduction lead to variation? (Crossing over, random union).
- Does the father's blood group affect the child's dominance traits? (Briefly explain inheritance).
- What are acquired traits? Are they inherited? (No).
- Give one example of an inherited trait and one of an acquired trait.
