10.1 bio

Question 1

order and events of cell cycle

Answer 1

G1- growth and normal cellular functions, preparation for replication of DNA

S- DNA replication occurs

G2- Cell continues to grow, produces more organelles, proteins, and membranes in preparation for division

M- DNA divides, than the cytoplasm divides

(G0- Cell leaves the cell cycle to rest or differentiate)

Question 2

examples and roles stimulatory proteins (growth factors, cyclins, cdks)

Answer 2

Growth factors—small proteins that circulate in the bloodstream—stimulate signals inside cells that cause G1-phase cyclin concentrations to rise.

The cyclins bind to the appropriate CDKs, which then phosphorylate other proteins to drive the cell cycle into S phase.

CDK-cyclin complexes signal the cell to duplicate its DNA.

Question 3

examples and roles of inhibitory proteins (p53)

Answer 3

if DNA is damaged, the p53 protein will stop cell cycle progression until the damage is repaired.

Question 4

Definitions and examples of proto-oncogenes and tumor suppressor genes

Answer 4

Proto-oncogenes are normal genes that promote cell growth and division, while tumor suppressor genes normally act to inhibit cell growth and prevent uncontrolled cell division.