Cell Cycle and mitosis

Question 1

steps of the cell cycle

Answer 1

CELL CYCLE: sequences of events that lead to cell growth and division

G0= when the cell is not replicating
G1 - growth 1, cell grows to accommodate new genetic information
S - synthesis, cell duplicates DNA in preparation for mitosis
G2 - growth 2, cell grows again for there to be enough cytoplasm for both daughter cells
M - mitosis, cell divides into two genetically identical diploid cells
(G1→G2 = interphase)

Question 2

steps of mitosis

Answer 2

prophase→metaphase→anaphase→telophase

Question 3

what happens during prophase

Answer 3

loose DNA or chromatin in the nucleus is super coiled into chromosomes. The nucleus disintegrates and the chromosomes are then released into the cytoplasm. The chromosomes then exist as sister chromatids. Centrioles move to either pole of the cell and spindle fibers begin to form.

Question 4

what happens during metaphase

Answer 4

spindle fibers attach themselves to the centromeres of the sister chromatids, aligning them at the equator of the cell.

Question 5

what happens during anaphase

Answer 5

the spindle fibers pull apart the sister chromatids, splitting them at the centromeres. The chromosomes are moved to either pole, and the spindle fibers begin to disintegrate.

Question 6

what happens during telophase

Answer 6

nuclear envelopes form around the chromosomes on either side, creating two nuclei. A nuclear membrane prepares to split the cytoplasm.

Question 7

what happens during cytokinesis

Answer 7

this is not actually part of mitosis, but occurs directly after. During cytokinesis the cytoplasm of the cell is split creating two genetically identical diploid cells (each 2n). Inside of either nucleus, the chromosomes go back to existing as chromatin or loose DNA.

Question 8

what is chromatin

Answer 8

loose DNA in the membrane

Question 9

what are chromosomes

Answer 9

supercoiled DNA

Question 10

what are chromatids

Answer 10

chromosomes existing as sister chromatids

Question 11

what are genetically identical diploid cells

Answer 11

• parental cell with 2N chromosomes, 2 daughter cells with 2N chromosomes
• cells with the same DNA and genetic makeup who also contain the same amount of chromosomes

Question 12

why are centrioles (centrosomes)

Answer 12

-organelle, tube like structure, involved in the formation of spindle fibers

Question 13

what are spindle fibers

Answer 13

direct chromosome movement

Question 14

what are centromeres

Answer 14

-constriction points that divides the chromosomes into 2 sections

Question 15

when does a cell divide

Answer 15

• during asexual reproduction
• during development or growth
• during repair

Question 16

what cells divide by the cell cycle and MITOSIS

Answer 16

-somatic cells

Question 17

what is mitosis

Answer 17

production of 2 new haploid daughter cells from one diploid parental cell
-daughter cells are genetically identical to parental cell (same number of chromosomes and same genes)

Question 18

what are homologous chromosomes

Answer 18

-2 identical chromosomes, one maternal and one paternal

Question 19

are sex cells homologous

Answer 19

nah, X and Y aren’t the same brah

Question 20

what happens during interphase

Answer 20

(precedes mitosis) chromosomes replicate

Question 21

how many chromosomes are there

Answer 21

46 chromosomes