Mitosis and Meiosis

Question 1

What are the two types of cell division?

Answer 1

Mitosis and meiosis

Question 2

What is a metacentric chromosome?

Answer 2

x shaped chromosomes with the centromere in the middle so that the two arms of the chromosomes are almost equal

Question 3

what is an acrocentric chromosome?

Answer 3

A chromosome in which the centromere is located quite near one end of the chromosome

Question 4

• Label the following diagram with: sister chromatids, non sister chromatids, non homologous chromosomes, homologous chromosomes

Answer 4

there

Question 5

In a human, how long does mitosis last in the cell cycle?

Answer 5

2 hours

Question 6

how long does g1 last

Answer 6

11 hours

Question 7

how long does s phase last

Answer 7

7 hours

Question 8

how long does g2 last

Answer 8

4 hours

Question 9

describe the different phases of the cell cycle

Answer 9

interphase, prophase, metaphase, anaphase, telophase

Question 10

What part is interphase?

Answer 10

Interphase is the phase of the cell cycle in which a typical cell spends most of its life. During this phase, the cell copies its DNA in preparation for mitosis. - everything except mitosis

Question 11

what phases are in mitosis

Answer 11

prophase, metaphase, anaphase and telophase

Question 12

what happens to the chromosomes in prophase of mitosis?

Answer 12

the chromosomes condense and become visible

Question 13

what happens to the centrosomes in prophase of mitosis?

Answer 13

they move apart toward opposite poles and generate new microtubules

Question 14

what happens to the nucleoli in prophase of mitosis?

Answer 14

they begin to disappear

Question 15

*what is a microtubule?

Answer 15

Microtubules are filamentous intracellular structures that are responsible for various kinds of movements in all eukaryotic cells.

Question 16

in metaphase of mitosis what happens to the chromosomes?

Answer 16

the chromosomes align on the metaphase plate with sister chromatids facing opposite poles

Question 17

in anaphase of mitosis what happens to the centromeres

Answer 17

they divide

Question 18

in anaphase of mitosis what happens to the sister chromatids once the centromeres have been divided?

Answer 18

the sister chromatids move to opposite poles

Question 19

what happens to the nuclear membranes and nucleoli in telophase of mitosis

Answer 19

they reform

Question 20

what happens to the spindle fibres during telophase of mitosis

Answer 20

they disappear

Question 21

what happens to the chromosomes in telophase of mitosis

Answer 21

they uncoil and become a tangle of chromatin

Question 22

*what happens during cytokinesis in an animal cell

Answer 22

a cleavage furrow forms and the cells divide

Question 23

*what happens during cytokinesis in a plant cell

Answer 23

a cell plate forms between the cells and they divide

Question 24

what is the problem with sex

Answer 24

only half the genes are transmitted from each parent so each individual is less efficient at passing its genome to the next generation, problem compounded when you have two sexes

Question 25

what is the main advantage of sex

Answer 25

the main advantage is the shuffling of genes, providing variation from which selection can act

Question 26

list all the stages of meiosis haha this might be a long ting

Answer 26

meiosis 1- prophase 1 - leptotene, zygotene, pachytene, diplotene, diakineses. metaphase 1, anaphase 1, telophase 1. INTERKINESIS meiosis 2 - prophase 2, metaphase 2, anaphase 2, telophase 2

Question 27

list the stages of prophase 1

Answer 27

leptotene, zygotene, pachytene, diplotene, diakinesis

Question 28

what happens to the chromosomes and chromatids in leptotene of prophase 1 in meiosis

Answer 28

they thicken and become visible but the chromatids remain invisible

Question 29

what happens to the centromeres in leptotene of prophase 1 of meiosis

Answer 29

the centromeres begin to move towards opposite poles

Question 30

what happens to the chromosomes in zygotene of prophase 1 of meiosis

Answer 30

the homologous chromosomes enter synapsis and the synaptonemal complex forms

Question 31

what happens to synapsis in pachytene of prophase 1 of meiosis

Answer 31

synpasis is complete baby!!!

Question 32

what is special that occurs in pachytene of prophase 1 of meiosis

Answer 32

crossing over

Question 33

what occurs in crossing over in pachytene

Answer 33

genetic exchange between non-sister chromatids of a homologous pair occurs

Question 34

what happens to the synatonemal complex in diplotene of prophase 1 of meiosis 1

Answer 34

the synaptenemal complex dissolves

Question 35

what can you see in diplotene in terms of chromatids

Answer 35

a tetrad of four chromatids is visible

Question 36

crossover points appear as what in diplotene of prophase 1 in meiosis 1

Answer 36

crossover points appear as chiasmata, which hold non sister chromosomes together

Question 37

in which stage does meiotic arrest occur in many species

Answer 37

prophase 1 of meiosis 1

Question 38

what happens to the chromatids in diakinesis of prophase 1

Answer 38

they thicken and shorten

Question 39

what happens at the end of prophase 1

Answer 39

the nuclear membrane breaks down and the spindle begins to form