Lab 6

Question 1

What is Mitosis?

Answer 1

-nuclear division that occurs in
* (1) occurs in the body (somatic) cells;
* (2) results in two daughter cells because there is only
one round of division
* (3) keeps the chromosome number constant (same as
the parent cell)

Question 2

Mitosis occurs only in

Answer 2

eukaryotic cells

Question 3

the major purpose of mitosis is

Answer 3

for growth and to replace worn-out cells

Question 4

The duration of cell division

Answer 4

10% time of cell cycle

Question 5

The cell cycle

Answer 5

G1+S+G2+M+C

Question 6

Interphase

Answer 6

G1+S+G2

Question 7

Cell division

Answer 7

M+C

Question 8

Eukaryotic cell division occurs in

Answer 8

2 different stages

Question 9

Mitosis divides the cells

Answer 9

nucleus

Question 10

CYTOKINESIS divides the cells

Answer 10

cytoplasm

Question 11

Before cell division, each chromosome is copied during which phase?

Answer 11

S phase

Question 12

Each chromosome consists of two identical

Answer 12

“sister” chromatids

Question 13

When the cell divides, the chromatids separate. Each daughter cell gets one chromatid, so they have the

Answer 13

same number of chromosomes as the parent cell

Question 14

what are the 5 stages of mitosis?

Answer 14

• Prophase
• Prometaphase
• Metaphase
• Anaphase
• telophase

PPMAT

Question 15

Interphase

Answer 15

Chromatin is condensing into chromosomes

Question 16

Prophase

Answer 16

• Duplicated chromosomes are
  visible.
• Nucleolus is disappeared.

*Nuclear membrane begins to
dissolve.

Question 17

Prometaphase

Answer 17

• Nuclear membrane has completely dissolves

Question 18

Metaphase

Answer 18

Centromeres of duplicated chromosomes are aligned at the metaphase plate (center of fully formed spindle)

Question 19

Anaphase

Answer 19

Sister chromatids part and become daughter chromosomes that move toward the spindle poles

Question 20

Telophase

Answer 20

• At each pole of the cell a full set of chromosomes gather together.
• A membrane forms around each set of chromosomes to create two new nuclei

Question 21

Mitosis in animal cells

Answer 21

Formation of asters with centrioles and of a
cleavage furrow are distinctive features

Question 22

Mitosis in Plant cells

Answer 22

Cytokinesis involves the formation of a cell plate
* Spindle apparatus has centrosome, but no centriole

Question 23

what is meiosis?

Answer 23

involves an additional round of chromosome separation, also called “reduction division”

• Occurs in gametes (sex cells)
• Result is a set of haploid (n) cells from a single
  diploid (2n) cell

Question 24

Diploid

Answer 24

Having the full chromosome number

Question 25

Haploid

Answer 25

Having half the full chromosome number

Question 26

What are homologous chromosomes?

Answer 26

matching pairs of chromosomes that carry genes for same traits.

Question 27

What are sister chromatids?

Answer 27

identical copies of chromosome made during the S phase of interphase, must have same allele forms

Question 28

how many processes of division are in meiosis?

Answer 28

2

Question 29

what is meiosis 1?

Answer 29

involves nearly identical phases as mitosis (prophase I, metaphase I, anaphase I, telophase I) but bivalents are paired during metaphase (crossing-over).

Question 30

What is Meiosis 2?

Answer 30

involves a second round of division (prophase II, metaphase II, anaphase II, telophase II), but the sister chromatids of each chromosome are separated during anaphase II. * result in four haploid(n) cells.

Question 31

what happens during prophase I of meiosis ?

Answer 31

each chromosome (pair of sister chromatids) pairs with its homologue to form a bivalent. * this pairing of homologous chromosomes is called synapsis

Question 32

what happens during synapsis?

Answer 32

the four chromatids exchange homologous segments of genetic material (alleles) in a process called crossing-over * produces new genetic combinations

Question 33

know this

Answer 33

2n=6 MITOSIS 2n=6 Diploid 2n=6 MEIOSIS I n=3 Haploid

Question 34

Gametogenesis

Answer 34

Formation of haploid gametes from diploid cells by the process of meiosis

Question 35

Fusion of haploid sperm (n) and haploid egg (n) (created by meiotic division) during _______ produces a diploid zygote (2n).

Answer 35

fertilization

Question 36

Somatic cells

Answer 36

*These create all tissues and organs of the adult. *They can only undergo mitosis.

Question 37

Germline Cells

Answer 37

*The final differentiated form of these cells are mature gametes: the sperm and egg. *These cells undergo mitosis until gametogenesis, then undergo meiosis.