Eukaryotic Cell Cycle

Question 1

Interphase

Answer 1

in between when the cells are dividing

Question 2

G1

Answer 2

cell growth and differentiation

-fully maturing to be what the cell is supposed to be

Question 3

G0

Answer 3

• non-dividing stage
• doing the job it is supposed to do
• most of the time cells are in this phase
• only re-enter the cycle when we need more cells
• -nerve cells are forever in this stage
• -cancer cells never go into this stage

Question 4

S

Answer 4

Synthesis of DNA; chromosomes are duplicated

-at the end of this stage we will have 46 duplicated chromosomes

Question 5

G2

Answer 5

Cell growth

-making more of everything for when the cell divides into two, so there is enough for both cells

Question 6

Mitosis

Answer 6

Equal division of the genetic material

-division of 1 diploid(2n) cell into 2 diploid(2n) cells

Question 7

diploid cells

Answer 7

have two copies of every gene

-homologous pairs of all the chromosomes

Question 8

What are the 4 stages to Mitosis Division?

Answer 8

1. Prophase
2. Metaphase
3. Anaphase
4. Telophase

Question 9

Prophase

Answer 9

• Chromosomes condense
• spindles form
• centrioles go to opposite poles
• the nuclear envelope breaks down
• spindles attach to kineticore of each chromosome
• -begin to guide them to the center or equator of the cell

Question 10

centrioles

Answer 10

proteins that guide spindles

Question 11

Metaphase

Answer 11

• Chromosomes line up ate the equator of the cell

- -there is no order to the line up

Question 12

Anaphase

Answer 12

• Chromosomes separate
• Spindles elongate- elongating the cell
• 46 unduplicated chromosomes are pulled towards the centrioles on different sides of the cell

Question 13

Telophase

Answer 13

• begins when chromosomes reach centrioles
• chromosomes are released from the spindles
• chromosomes uncoil/uncondense
• new nuclear envelope is formed

Question 14

Cytokinesis

Answer 14

• division of cytoplasm (dividing everything else up)
• micro-filaments pinch off the cells
• 2 daughter cells with the same number of chromosomes as the parent cell (diploid/2n)

Question 15

Meiosis (Meiotic Cell Division)

Answer 15

• Key to sexual reproduction
• production of sperm / eggs
• 1 diploid(2n) cell dividing into 4 haploid(n) cells
• 2 rounds of division (Meiosis I and Meiosis II)
• involves genetic recombination

Question 16

Genetic Recombination

Answer 16

• cross over of homologous chromosomes
• trades some genes, different alleles
• -random on each chromosome, but must trade the same gene type
• increases genetic variability

Question 17

Meiosis I Phases

Answer 17

• Seperates homologous chromosomes into 2 haploid(n) daughter cells
  1. Prophase I
  2. Metaphase I
  3. Anaphase I
  4. Telophase

Question 18

Prophase I

Answer 18

• Chromosomes condense
• nuclear envelope breaks down
• homologous chromosomes line up together
• recombination occurs
• spindles form and attach to chromosomes at the kinetochore

Question 19

Metaphase I

Answer 19

• Chromosomes line up at the equator

- -homologous pairs will stay together

Question 20

Anaphase I

Answer 20

• Homologous pairs separate to opposite sides
• -sister chromatids stay together
• pulled be spindle microtubles

Question 21

Telophase

Answer 21

• spindles disappear
• nuclear envelope reforms
• cytokinesis occurs
• 2 daughter cells have 1 of each chromosome pair (duplicated)
• -haploid(n)

Question 22

Meiosis II

Answer 22

-separates sister chromatids to 2 haploid(n) daughter cells

Question 23

Prophase II

Answer 23

• Chromosomes re-condense
• nuclear envelope breaks down
• spindle reforms and attaches to chromosomes at the kineticore

Question 24

Metaphase II

Answer 24

-Chromosomes line up at the equator of the cell

Question 25

Anaphase II

Answer 25

• Chromosomes separate
• Chromosomes are pulled towards the centriole
• Spindle elongates- elongating the cell

Question 26

Telophase II

Answer 26

• begins when chromosomes reach centrioles
• chromosomes released from tubules
• -uncoil-uncondense
• new nuclear envelope fromed

Question 27

Cytokinesis of Meitosis

Answer 27

• 4 daughter cells with 1 copy of each chromosomes

- -haploid (n)