CH 12

Question 1

Cell division

Answer 1

-The continuity of life is based on the reproduction of cells

Question 2

Genome

Answer 2

can consist of a single DNA molecule or a number of DNA molecules

Question 3

Chromosomes

Answer 3

-a cellular structure consisting of one DNA molecule and associated protein molecules

Question 4

Chromatin

Answer 4

-a complex of DNA and protein that condenses during cell division

Question 5

Somatic cells

Answer 5

-nonreproductive cells
-have two sets of chromosomes

Question 6

Gametes

Answer 6

-reproductive cells–sperm and egg
-have half as many chromosomes as somatic cells

Question 7

Sister chromatids

Answer 7

-joined copies of the original chromosome

Question 8

Centromere

Answer 8

-the narrow “waist” of the duplicated chromosome, where the two chromatids are most closly attached

Question 9

Mitosis

Answer 9

-the division of the genetic material in the nucleus

Question 10

Cytokinesis

Answer 10

-division of the cytoplasm

Question 11

Miotic (M) phase

Answer 11

-mitosis and cytokinesis

Question 12

Interphase

Answer 12

-cell growth and copying of chromosomes in preparation for cell division

Question 13

Interphase three phases

Answer 13

-G1 phase (“first gap”)
-S phase (“synthesis”)
-G2 phase (“second gap”)

Question 14

5 phases of mitosis

Answer 14

-prophase
-prometaphase
-metaphase
-anaphase
-telophase

Question 15

Mitotic spindle

Answer 15

-structure made of microtubules that controls chromosome movement during mitosis

Question 16

Centrosome

Answer 16

-microtubule-organizing center
-replicates during interphase

Question 17

Kinetochores

Answer 17

-protein complexes associated with centromeres

Question 18

Metaphase plate

Answer 18

-a plane midway between the spindle’s two poles

Question 19

Cleavage

Answer 19

-process of cytokinesis in animal cells

Question 20

Cleavage furrow

Answer 20

-a shallow grove on the cells surface

Question 21

Cell plate

Answer 21

-formed during cytokinesis

Question 22

Binary fission

Answer 22

-a type of cell division where prokaryotes (bacteria and archaea) reproduce

Question 23

Origin of replication

Answer 23

-site where the replication of a DNA molecule begins

Question 24

Cell cycle control system

Answer 24

-directs the sequential events of the cell cycle
-like a clock

Question 25

Checkpoints

Answer 25

-cell cycle stops until a go-ahead signal is received

Question 26

Cyclins & Cyclin-dependent kinases (Cdks)

Answer 26

-regulatory protein involved in cell cycle control

Question 27

MPF (maturation-promoting factor)

Answer 27

-a cyclin-Cdk complex that triggers a cell’s passage past the G2 checkpoint into the M phase

Question 28

G0 phase

Answer 28

-If the cell does not receive the go-ahead signal, it will exit the cycle, switching into a nondividing state

Question 29

Growth factors

Answer 29

-released by certain cells and stimulate other cells to divide

Question 30

Density-dependent inhibition

Answer 30

-crowded cells will stop dividing

Question 31

Anchorage dependence

Answer 31

-the requirement that a cell must be attached to a substratum in order to initiate cell division

Question 32

Transformation

Answer 32

-process by which a cell acquires the ability to divide indefinitely

Question 33

Benign tumor

Answer 33

-when abnormal cells remain only at the original cite and forms a lump

Question 34

Malignant tumor

Answer 34

-invades surrounding tissues and spreads

Question 35

Metastasis

Answer 35

-the spread of cancer cells to locations distant from their original sites