mitosis and meiosis

Question 1

What are the 4 stages of the cell cycle?

Answer 1

first growth phase (growth and normal metabolic roles), synthesis phase (DNA replication), second growth phase (growth and preparaion of mitosis), mitotic phase (prophase, metaphase, anaphase and telophase)

Question 2

what are the 7 stages of mitosis?

Answer 2

interphase, prohpase, prometaphase, metaphase, anaphase, telophase, cytokensis

Question 3

describe interphase

Answer 3

mitosis stage 1

chromosomes duplicate, and the copies remain attached to each other

Question 4

describe prophase

Answer 4

mitosis stage 2

in the nucleas chromosomes condense and become visible. In the cytoplasm the spindle forms

Question 5

described prometaphase

Answer 5

mitosis stage 3

the nuclear membrane breaks apart, and the spindle starts to interact with the chromosomes

Question 6

describe metaphase

Answer 6

mitosis stage 4

the copied chromosomes align in the middle of the spindle

Question 7

described anaphase

Answer 7

mitosis stage 5

chromosomes separates into two genetically identical groups and move to opposite ends of the spindle

Question 8

describe telophase

Answer 8

mitosis stage 6
nuclear membranes form around each of the two sets of chromosomes, the chromosomes begin to spread out and the spindle begins to break down

Question 9

described cytokinesis

Answer 9

final stage of mitosis
the cell splits into two daughter cells, each with the same number of chromosomes. In humans, such cells have two copies of 23 chromosomes and are called diploid.

Question 10

what is meiosis

Answer 10

a specific form of cell division, which is used in the formation of gametes. It is a two stage process, resutling in four haploid cells.

Haploid- when a cell has half the usual number of chromosomes
Diploid- when a cell has paired chromosomes

Question 11

What are the 8 stages of meiosis?

Answer 11

prophasse 1, metaphase 1, anaphase 1, telophase 1 and cytokinesis, prophase 2, metaphase 2, anaphase 2, telophase 2 and cytokinesis

Question 12

describe meiosis prophase 1

Answer 12

the chromosomes condense, and the nuclear envelope breaks down. crossing-over occurs

Question 13

describe meiosis metaphase 1

Answer 13

pairs of homologous chromosomes move to the equator of the cell

Question 14

describe meiosis anaphase 1

Answer 14

homologous chromosomes move to the opposite poles of the cell

Question 15

describe meiosis telophase 1 and cytokinesis

Answer 15

chromosomes gather at the poles of the cells. the cytoplasm divides

Question 16

describe meiosis prophase 2

Answer 16

a new spindle forms around the chromosomes

Question 17

described meiosis metaphase 2

Answer 17

chromosomes line up at the equator

Question 18

describe meiosis anaphase 2

Answer 18

centromeres divides. chromatids move to the opposite poles of the cells

Question 19

describe meiosis telophase 2 and cytokinesis

Answer 19

a nuclear envelope forms around each set of chromosomes. the cytoplasm divides

Question 20

three causes of genetic variation

Answer 20

aside from mutations, genetic variation can arise from:

independent assortment of chromosomes

crossing over

random fertilization

Question 21

mitosis is an important process for…?

Answer 21

growth, replacement, regeneration

Question 22

what is the microtubule organising centre?

Answer 22

centrosomes

Question 23

what do the microtubules attach to?

Answer 23

the centromere/kinetochore

Question 24

what is crossing over and when does it occur?

Answer 24

the swapping of genetic information at the chiasmata during prophase 1

Question 25

what does meiosis result in?

Answer 25

4 haploid daughter cells