Chapter 12

Question 1

What is cytokinesis?

Answer 1

Cytoplasm of the cell divides into two distinct daughter cells

Question 2

General def of mitosis

Answer 2

Production of somatic cells ; daughter cells are genetically identical to parent cell

Question 3

General def of meiosis

Answer 3

Production of gametes(egg and sperm) ; daughter cells have half the amount of genetic material as parent cell.

Question 4

Chromosome

Answer 4

Structure consisting of DNA and associated proteins that carries and transmits genetic information ; unreplicated=single DNA strand, replicated=2 sister chromatids

Question 5

Interphase G1

Answer 5

Cell grows ; cellular metabolic activity is high ; organelles are duplicated

Question 6

Interphase S

Answer 6

DNA duplicates

Question 7

Interphase G2

Answer 7

Ensures errors have not been made during DNA replication ; final prep for cell division ; beginning organization of spindle

Question 8

What happens if too many errors have been made?

Answer 8

Guardian proteins are then responsible for preventing the cell cycle from moving forward until the error is corrected

Question 9

G0 checkpoint

Answer 9

Cell cycle arrest

Question 10

G1 checkpoint

Answer 10

Cellular contents, excluding the chromosomes, are duplicated

Question 11

S checkpoint

Answer 11

Each of 46 chromosomes are duplicated by cell

Question 12

G2 checkpoint

Answer 12

Cell “double checks” the duplicated chromosomes for error, making any needed repairs

Question 13

Phases of mitosis

Answer 13

Interphase, prophase, prometaphase, metaphase, anaphase, telophase

Question 14

MPF

Answer 14

Maturation-promoting factor ; cyclin-cdk complex that triggers a cell to move past the G2 checkpoint into M phase

Question 15

What do growth factors do?

Answer 15

Stimulate other cells to divide

Question 16

PDGF

Answer 16

Platelet-derived growth factor ; made by platelets and is required for division of cultured fibroblasts

Question 17

Anchorage dependence

Answer 17

To divide they must be attached to a substratum ; require a surface

Question 18

Density-dependent inhibition

Answer 18

Crowded cells will stop dividing ; cells for, a single layer ; cells divide to fill a gap and then stop

Question 19

Two types of cancer cell defects

Answer 19

Makes proteins required for cell growth active active when they shouldn’t be ; prevents tumor suppressor genes from shutting down the cell type

Question 20

Metastasize

Answer 20

Travel to other parts of the body to form a new tumor