3.3.2 to 3.3.4

Question 1

tetrad (bivalent)

Answer 1

4 homologues chromatids OR 2 homologous chromosomes

Question 2

crossing over

Answer 2

creates new combinations of alleles that weren’t present in either original chromosome

Question 3

reduction division

Answer 3

daughter cells contain only half of the chromosomes that were present in the parent cell

Question 4

random orientation

Answer 4

when the pairs of homologous chromosomes move to opposite poles, each chromosome can end up at either pole

Question 5

genetic variation

Answer 5

the raw material on which natural selection acts

Question 6

how is genetic variation increased by?

Answer 6

• original source=mutations

further increase by meiosis in 2 individuals AND alleles form 2 organisms=combine in novel ways

also sexual reproduction, allows existing variations shuffled into endless new factors

Question 7

independent assortment

Answer 7

in random orientation, where allele inherited for 1 gene won’t affect the allele inherited for another

Question 8

2^n

Answer 8

the number of possible chromosome combinations in the gametes, where n is the haploid number of chromosomes