Question 1
Unit 2 style
Which event in meiosis results in independent assortment of chromosomes?
- Crossing over in prophase I
- Random orientation of homologous pairs in metaphase I
- Separation of sister chromatids in anaphase II
- Replication of DNA before meiosis I
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Question 2
Unit 2 style
What is the function of the cortical reaction in fertilisation?
- To digest a path through the zona pellucida
- To fuse the nuclei of the sperm and egg
- To prevent more than one sperm entering the egg
- To provide energy for the movement of the sperm
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Question 3
Unit 2 style
Define the term locus. Explain why two genes on the same chromosome may not be inherited independently.
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Question 4
Unit 2 style
Explain how meiosis produces genetically different gametes.
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Question 5
Unit 2 style
The domestic cat has a haploid number of 19 chromosomes. Calculate the number of different combinations of chromosomes that can occur in the gametes of one cat because of independent assortment alone. Show your working.
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Question 6
Unit 2 style
Describe how a mammalian sperm cell is adapted for its function.
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Question 7
Unit 2 style
Describe the events that take place from the time a sperm reaches the zona pellucida of an egg until a zygote forms.
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Question 8
Unit 2 style
Describe how fertilisation takes place in a flowering plant, from the arrival of a pollen grain at the stigma.