Crossing-over of parts of chromosomes:
a. has no effect on genetic linkage
b. usually decreases the number of genetic combinations
c. can increase the number of genetic combinations
Crossing-over resulting in the inheritance of altered chromosomes by children occurs:
a. during mitosis
b. during meiosis
c. both a and b
For the first question:
c. can increase the number of genetic combinations
Crossing-over during meiosis allows for the exchange of genetic material between homologous chromosomes, leading to new combinations of genes in the resulting gametes. This increases genetic diversity in the offspring.
For the second question:
b. during meiosis
Crossing-over occurs during meiosis, specifically in prophase I, where homologous chromosomes align and exchange segments. This process does not occur during mitosis, where the chromosome structure remains intact.
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