W1-L7-cell replication

Question 1

why appropriate cell division?

Answer 1

could lead to cell death
mutation to oncogenes and tumour suppressor genes or aneuploid
chromosomes instability
perturbation of protein lvls in cell cycle
contact inhibition growth

Question 2

what is a cell cycle?

Answer 2

orderly sequence of events in which a cell duplicates its content and divides into 2
aka duplication division and coordination

Question 3

why is mitosis the most vulnerable period of the cell cycle?

Answer 3

cells more easily killed by irradiation, heat shock and chemicals
DNA damage cannot be repaired
Genes transcription silenced
metabolism slowed?

Question 4

phases of a cell cycle

Answer 4

M phase (division) and interphase (duplication)

Question 5

eukaryotic cells cycle stages

Answer 5

M phase- mitosis takes place
G0- cells is not dividing but carry out its function-dismantled of cell cycle machinery
G1- decision point to enter cell cycle
S phase-synthesis of DNA and protein
G2-decision point to enter mitosis

Question 6

s-phase

Answer 6

protein synthesis and replication of organelles

Question 7

protein synthesis

Answer 7

translation initiation and elongation increased

capacity also increased

Question 8

replication of organelles

Answer 8

e.g. centrosomes, mitochondria and Golgi body replicates

note that mitochondria should coordinate its DNA replication

Question 9

function of centrosome and life cycle in mitosis

Answer 9

MTOC or mitotic spindle

protrudes out of centrioles nucleating sites

Question 10

what are mitosis 6 stages

Answer 10

prophase, pro-metaphase, metaphase, anaphase, telophase, cytokinesis

Question 11

chromatin condensation

Answer 11

shortened region of DNA double helix-2nm

Question 12

what happens during prophase 1 and 2

Answer 12

condensation of chromosomes