Cht 12 The Cell Cycle

Question 0

Gap 1 phase

G1

Answer 0

Growth of the cell and synthesis of cytoplasmic organelles
Interphase
G1 checkpoint: good to go on if not then goes to G0

Question 1

Cell cycle

Answer 1

Events that occur in a cell from the time it is formed by mitosis, until it divides into 2 daughter cells.
G1, S, G2, M, C

Question 2

Synthesis

S

Answer 2

DNA replication

Interphase

Question 3

Gap 2 phase

G2

Answer 3

Synthesis of structure involved in the cell division
(ex. Microtubules)
Interphase

Question 4

Mitosis

M

Answer 4

Mitosis= karyokinesis “chromosomes splitting”
Chromosomes condense and separate into 2 nuclei.
Interphase, prophase, metaphase, anaphase, telophase

Question 5

Cytokinesis

C

Answer 5

“Cell splitting” the cytoplasm separates into 2 cells

Question 6

Chromosome

Answer 6

A strand of DNA that has wound up tightly (causing it to be visible in the microscope) (X)

Question 7

Centromere

Answer 7

Constricted region of the chromosome with associated proteins
(X dot in the middle) use to count the number of chromosomes

Question 8

Sister chromatids

Answer 8

2 identical copies of the same chromosome (XX)

Question 9

Homologous chromosome

Answer 9

Chromosomes that are the same length
Centromeres in the same location
Carry genes for the same traits (eye color, blood type)
One from dad. One from mom

Question 10

Interphase (5)

Answer 10

• No condensation of the chromatin.
• Can’t tell the number of chromosomes in the cell by looking thru microscope.
• Nuclear envelope present.
• Nucleolus present at nucleoplasm organizer region.
• Centrosomes paired side-by-side (not found in plants)

Question 11

Prophase (5)

Answer 11

• Chromatin condenses into chromosomes.
• Chromosomes massed in center of cell.
• Nuclear envelope disappears.
• Nucleolus disappears.
• Spindle fibers (microtubules) forming. Attach to kinetochores (proteins) of each sister chromatid that push and pull chromosomes into place.

Question 12

Metaphase (2)

Answer 12

Chromosomes are fully condensed.

Chromosomes lined up at the metaphase plate by the spindle fibers (1X1).

Question 13

Anaphase (1)

Answer 13

Spindle fibers push and pull sister chromatids to separate poles of the cell.

Question 14

Telophase (5)

Answer 14

Two nuclei are forming. 
Chromosomes unwind into chromatin. 
Nuclear envelopes reappear. 
Nucleoli reappear. 
Spindle fibers break down.

Question 15

Karyokinesis

Answer 15

Notice that the nucleus has first divided into two.

Question 16

Cytokinesis

Answer 16

The cytoplasm then divides into two daughter cells, each with one nucleus.
Animal cells pinch in two. (Cleavage furrow)
Plant cells grow a new cell wall from cell plate.

Question 17

Mitosis results in…

Answer 17

2 daughter cells with the same number of chromosomes as the original parents cell. Somatic (body) cells are the result.