Cell Cycle

Question 1

What part of the cell cycle exists at the early embryonic phase

Answer 1

DNA synthesis (S phase)

Question 2

What regulates movement through cell cycle

Answer 2

Cyclins or CDK

Question 3

G0 Gap )

Answer 3

Not actively replicating and has left the cell cycle. Happens in specialized cell once they differentiate they stay here. Some enter and leave and some never enter

Question 4

Labile cells

Answer 4

Cell always in the cell cycle

Question 5

Stable cells

Answer 5

Cells usually in G0 but can enter cell cycle

Question 6

Permanent cells

Answer 6

Cells that do not enter the cell cycle

Question 7

Interphase

Answer 7

Grow and develop in order to divide. Consists of Gap 1, S phase, Gap 2

Question 8

Gap 1

Answer 8

Rapid cell growth, increase organelles, proteins and biosynthesis

Question 9

S phase

Answer 9

DNA synthesis

Question 10

G2 phase

Answer 10

Rapid growth and protein synthesis, has 2x DNA and must be checked for DNA damage before going to the next phase

Question 11

M phase

Answer 11

Nuclear division (Prophase, prometaphase, metaphase, anaphase, telophase)

Question 12

G1 checkpoint

Answer 12

Regulated by G1/S cyclins. Must have enough materials to pass

Question 13

G2/M checkpoint

Answer 13

Check for DNA damage. Regulated by p53

Question 14

Metaphase checkpoint

Answer 14

Make sure chromosomes aligned before anaphase

Question 15

Aplasia cutis congenita

Answer 15

Focal or widespread absence of skin. Caused by mutation that caused by p21 mediated G1/S phase cell cycle transition delay so skin can not grow

Question 16

Epitheliogenesis imperfecta

Answer 16

Absence of focal areas of skin. Happens in many species see in the limbs or oral mucosa as well as other places. See other anomalies that accompany it.

Question 17

Canine mammary tumors

Answer 17

Most frequent tumor in intact female dogs, certain breeds more susceptible. See problems in p53, BRCA1 and 2 and others

Question 18

p53

Answer 18

Most frequently mutated gene in human neoplasia. See mutations in this in dogs with many types of cancer as well. Facilitates DNA repair or triggers apoptosis

Question 19

Defects in p53

Answer 19

Can result in failure to arrest cycle at G1/S or to activate apoptosis on genetically abnormal cells

Question 20

Chronic kidney disease

Answer 20

Bid deal in old cats. Pathologically there is chronic tubulointerstitial inflammation and fibrosis

Question 21

TGF-B1

Answer 21

Activates genes that induce ECM production (fibrosis). Induces epithelial cells to turn to fibrous cells. Induce apoptosis at high concentration. Causes G2/M arrest in kidney through p21