Topic 4-2

Question 1

what is the purpose of meiosis?

Answer 1

to produce gametes for sexual reproduction

Question 2

most _______ cells are diploid cells

Answer 2

eukaryotic

Question 3

why is it necessary to reduce the number of chormosomes in each cell during meiosis?

Answer 3

so that you don’t double the number of chromosomes with each generation

Question 4

a mature haploid male or female germ cell

Answer 4

gametes

Question 5

what are the three main stages of the cell cycle in a meiotic cell?

Answer 5

• interphase
• meiosis I
• meiosis II

Question 6

meiosis I is known as the __________ division phase

Answer 6

reductional

Question 7

meiosis II is known as the _________ division phase

Answer 7

equatorial

Question 8

during late prophase I, homologous chromosomes pair up and DNA arms ‘crossover’, forming:

Answer 8

chiasmata

Question 9

what is the chiasmata?

Answer 9

the location at which the chromosome arms link to exchange genetic info

Question 10

the close pairing of homologous chromosomes during meiosis I

Answer 10

synapsis

Question 11

closely associated four sister chromatids of two homologous chromosomes

Answer 11

tetrad

Question 12

why does “crossing over” occur during meiosis I

Answer 12

helpful for generating genetic variation in newly formed gametes

Question 13

what is interkinesis?

Answer 13

interphase II, a period of rest between telophase I and prophase II

Question 14

unlike mitosis, the daughter cells in meiosis are:

Answer 14

genetically variable

Question 15

what is the purpose of the cohesin rings around the chiasmata?

Answer 15

hold homologous pairs of chromosomes together

Question 16

what is the purpose of the cohesin rings around the centromeres?

Answer 16

hold sister chromatids together

Question 17

the protein that protects the sister chromatid cohesin

Answer 17

shugoshin

Question 18

what is the main purpose of shugoshin?

Answer 18

prevents the separation of sister chromatids during anaphase I

Question 19

what are the three genetic consequences of meiosis?

Answer 19

1) results in 4 daughter cells that are genetically variable
2) results in 4 daughter cells that hav half the number of chromosomes
3) daughter cells contain about half of the cytoplasm and half of the organelles