Cell Cycle - Lab 5

Question 1

Most Somatic cells:

Answer 1

Divide for growth and repair.

Question 2

The stages that a cell passes through from the time it is formed until it divides is called:

Answer 2

The cell cycle

Question 3

The cell cycle includes two main phases:

Answer 3

Interphase and Mitotic/meiotic

Question 4

Interphase:

Answer 4

The longest phase in the cell cycle

Question 5

Mitotic and meiotic

Answer 5

Somatic cell and germ cell
the M-phase

Question 6

Interphase stages:

Answer 6

G1 phase (gap 1)
S phase (synthesis phase)
G2 phase (gap 2)

Question 7

In the G1 phase, the cell is:

Answer 7

Growing in size

Question 8

In the S phase, the cell:

Answer 8

Replicates/duplicates its DNA and replicate the centriole.

Question 9

Duplicated chromosomes are held together by a structure called:

Answer 9

centromere

Question 10

In the G2 phase, the cell is:

Answer 10

Undergoes routine metabolism and continues to grow

Question 11

Microscopic appearance of the Interphase stage of
the animal and plant Cells (metabolic active cell):

Answer 11

Chromatin is dispersed
one or more nucleus is evident
transparent nuclear membrane

Question 12

M phase:

Answer 12

Mitosis or meiosis

Question 13

Mitosis

Answer 13

somatic cell

Question 14

Meiosis

Answer 14

germ cell

Question 15

Types of division that take place during mitosis

Answer 15

Cytokinesis and karyokinesis
(Cytoplasmic division and nucleus division)

Question 16

Mitosis is divided into 4 stages:

Answer 16

Prophase
metaphase
anaphase
telophase

Question 17

Prophase + light microscopic characteristics:

Answer 17

Longest phase of mitosis
Duplicate centioles move towards opposite poles of the cell (not seen by LM)
Chromosomes shorten and thicken (seen by LM)
nuclear membrane and nucleolus disappear. (seen
by LM)
Mitotic spindle start to from by the microtubules asters of
the centrioles

Question 18

Metaphase stage:

Answer 18

Condensed chromosomes line up along the equator by their centromeres to the spindle fibers

Question 19

Anaphase:

Answer 19

Chromosomes separate from each other (Break at centromere) and pulled towards opposite poles of the cell.

Question 20

Telophase

Answer 20

separated chromosomes start to form clear new nuclei in the newly formed daughter cell.
Spindle fibers disappear
Cytokinesis occurs

Question 21

Animal Cell cytokinesis:

Answer 21

Cell membrane pinches in
*Cleavage furrow & Contractile ring

Question 22

Plant Cell cytokinesis:

Answer 22

New cell wall Golgi vesicles form between two
nuclei to form the 2 new daughter cells separated by cell wall.
*Cell wall Golgi vesicles. -> Cell plate

Question 23

G0 phase:

Answer 23

cellular state outside of
the replicative cell cycle.
Resting phase.

Question 24

Cells that may stay in the G0 stage temporarily and
then inter the mitosis stage again are called:

Answer 24

quiescent cells

Question 25

Cells that may stay in the G0 stage permanently and
don’t inter the mitosis stage again are called:

Answer 25

senescent cells undergoing ageing and DNA damage

Question 26

meristem

Answer 26

Embryonic tissue where mitosis is occurring.

Question 27

elongation zone

Answer 27

Cells are long rectangles.
they are not undergoing mitosis.

Question 28

Onion root-tip cells have a cell cycle of:

Answer 28

24-hours (approximately)

Question 29

Mitosis can be studied in:

Answer 29

Onion or garlic root tip, animal cells of
tadpole tail, Fish blastula and epithelial cells of Fish
gills

Question 30

Stain used in the onion root tip experiment: (mitosis)

Answer 30

Acetocarmine

Question 31

The mitotic index is:

Answer 31

a measure of the growth
rate of a cell population

Question 32

The mitotic index may be elevated during

Answer 32

Normal growth
cancer cells
Cellular repair (wound healing)

Question 33

To calculate mitotic index

Answer 33

Cells in mitosis/total cells

Question 34

Materials used in onion root tip experiment:

Answer 34

Microscope with 40x, 100x, and 400x.
Prepared microscope slide of an onion root tip.
Worksheet for mitosis and mitotic index.