QUESTION 5 (6 marks)
Meiosis ensures that a wide range of genetic combinations occurs during the formation of gametes. The diagrams show two processes that occur during meiosis.
Describe the two processes shown in the diagrams and how they contribute to genetic variation in gametes.
Name and description of process 1:
Name and description of process 2:
QCAA guide · typeset solution
QCAA sample response and mark allocation
5 Crossing over: When segments of maternal and paternal
• for crossing over
chromosomes are exchanged during the process of meiosis,
- provides the name of the process
resulting in chromosomes containing DNA from each parent
[1 mark]
— new genetic combinations are produced at the
- describes the process [1 mark]
chromosome level.
- states how the process contributes to
Independent assortment: Maternal and paternal
genetic variation in gametes [1 mark]
chromosomes do not separate together; instead, each
• for independent assortment
haploid gamete cell will contain a mixture of chromosomes
- provides the name of the process
from each parent, providing new genetic combinations.
[1 mark] - describes the process [1 mark] - states how the process contributes to genetic variation in gametes [1 mark]
QCAA sample response and marking criteria reproduced from the official guide.
Compare your working with the guide above.