Reproduction

Question 1

the cell cycle: 4 stages

Answer 1

G1, S, G2, M
interphase = G1, S, and G2
G0 stage is for cells that are not actively dividing

Question 2

G1 stage

Answer 2

cell creates organelles and increases in size

restriction point must be reached before going to S phase (eg DNA must be complementary)

Question 3

S stage

Answer 3

genetic material replicated so that each daughter cell gets identical copies
chromosome turns into 2 daughter chromatids bound at the centromere
ploidy does not change!

Question 4

G2 stage

Answer 4

cell checks to ensure that there are enough organelles and cytoplasm to divide
also checks DNA replication to avoid passing on an error to daughter cells

Question 5

mitosis

Answer 5

prophase, metaphase, anaphase, telophase

ends with cytokinesis

Question 6

p53

Answer 6

protein which controls G1/S checkpoint aka restriction point for DNA quality control
if there has been damage to the DNA, the cell cycle goes into arrest until DNA can be repair

Question 7

cyclins and CDKs

Answer 7

cyclins and cyclin dependent kinases
molecules responsible for the cell cycle
concentrations of cyclins increase and decrease during specific stages
cyclins bind to CDKs to create an activated CDK-cyclin complex which will phosphorylate transcription factors

Question 8

transcription factors

Answer 8

mediated by CDK-cyclin complex during different stages

promote transcription of genes required for the next stage of the cell cycle

Question 9

meiosis I

Answer 9

reductional division

homologous chromosomes are separates, generating haploid (n) daughter cells from diploid (2n) parent cells

Question 10

meiosis II

Answer 10

equational division
separation of sister chromatids
daughter cells remain haploid (n)

Question 11

crossing over

Answer 11

during prophase I of meiosis I, chromatids of homologous chromosomes may break at the point of contact and exchange equivalent pieces of DNA

Question 12

Mendel’s law of independent assortment

Answer 12

inheritance of one allele has no effect on the likelihood of inheriting certain alleles for other genes
explained by crossing over/recombination

Question 13

Mendel’s law of segregation

Answer 13

anaphase I of meiosis I
two homologous chromosomes are separated and their distribution to the two intermediate daughter cells is random with respect to the parent cell

Question 14

SRY

Answer 14

sex-determining region Y
gene on the Y chromosome
codes for a transcription factor that initiates testis differentiation and the formation of male gonads