GCSE Biology Reproduction & DNA questions by topic

Complete the sentences about reproduction.

1. (a)Sexual reproduction involves the fusion of male and female __________.[1]
2. (b)Asexual reproduction produces genetically __________ offspring.[1]
3. (c)Meiosis produces __________ gametes from one cell.[1]
4. (d)At fertilisation, the full chromosome number is __________.[1]

Complete the DNA base-pairing table.

1. (a)Complete all four pairings.[4]

State one advantage and one disadvantage of asexual reproduction.

1. (a)One advantage.[2]
2. (b)One disadvantage.[2]

A DNA sample contains 22% guanine.

1. (a)Calculate the percentage of cytosine.[1]
2. (b)Calculate the percentage of adenine.[1]

This question is about how organisms reproduce.

1. (a)What fuses together in sexual reproduction?[1]
2. (b)What is a clone?[1]
3. (c)Name the type of cell division that makes gametes.[1]
4. (d)State one advantage of a population showing variation.[1]

A short section of one DNA strand reads: A – T – C – G. Give the sequence on the complementary strand.

1. (a)The base paired opposite the first A.[1]
2. (b)The base paired opposite the T.[1]
3. (c)The base paired opposite the C.[1]
4. (d)The full complementary sequence, in order.[1]

Describe meiosis and explain its importance in sexual reproduction.

1. (a)Describe what meiosis produces.[3]
2. (b)Explain why fertilisation restores the chromosome number.[2]
3. (c)State one other thing meiosis contributes.[1]

Compare sexual and asexual reproduction, and explain why the malaria parasite uses both.

1. (a)Give three differences.[3]
2. (b)Explain the benefit of using both strategies.[3]

Describe the structure of DNA.

1. (a)Describe the overall shape and building blocks.[3]
2. (b)State the base-pairing rules.[2]

A student claims mutations are always caused by radiation and always harmful. Assess this claim.

1. (a)Assess both parts of the claim.[4]
2. (b)State the correct summary of mutation effects.[1]

A chimpanzee body cell contains 48 chromosomes.

1. (a)How many chromosomes are in a chimpanzee sperm cell?[1]
2. (b)Describe what happens during meiosis.[2]
3. (c)Explain how fertilisation restores the body-cell number.[1]
4. (d)Explain why meiosis, not mitosis, is needed here.[1]

An analysis of a DNA sample shows it contains 18% thymine.

1. (a)State the percentage of adenine.[1]
2. (b)State the combined percentage of guanine and cytosine.[1]
3. (c)Calculate the percentage of guanine.[2]
4. (d)Explain the base-pairing rule your working relies on.[2]

(Higher) Explain how a gene in the nucleus results in a protein in the cytoplasm.

1. (a)Write a full explanation.[6]

A farmer’s entire asexually propagated banana crop is destroyed by a single fungal disease.

1. (a)Explain why one disease could destroy the whole crop.[3]
2. (b)Explain how sexual reproduction could help future crops.[3]

(Higher) A mutation changes one base in the gene for a digestive enzyme. Explain how this could change the person’s ability to digest food.

1. (a)Write a full causal chain.[6]

A student says: “Gametes are just small body cells.” Explain what is wrong with this statement.

1. (a)Explain the differences.[5]

Evaluate the statement: “Sexual reproduction is better than asexual reproduction.”

1. (a)Assess with evidence from both sides and reach a judgement.[6]

The Human Genome Project read the entire human genome.

1. (a)State what the term genome means.[2]
2. (b)Describe three ways this knowledge helps medicine.[3]
3. (c)Give one reason why a patient might decline a genome-based test.[1]