ch 10 exam 3

Question 1

What is Mitosis?

Answer 1

an identical copy of the parent is created
- Produces diploid cells (somatic, body cells)

Question 2

What is the cell cycle?

Answer 2

stages through which a cell passes from one cell division
to the next

Question 3

What is chromatin?

Answer 3

unraveled
form of chromosomes

Question 4

What are histones?

Answer 4

any of a group of basic proteins found in chromatin.

Question 4

What are chromosomes?

Answer 4

Chromatin wraps around histone proteins when division is about to occurs.
(This forms chromosomes)

Question 5

What is the characteristic number of chromosomes in humans?

Answer 5

46

Question 5

What are nucleosomes?

Question 6

What is diploid?

Answer 6

Somatic cells (body cells)
- a cell or nucleus contains two
sets of chromosomes.

Question 7

What is haploid?

Answer 7

Sex cells (gametes, sperm and egg)
-a cell or nucleus has only a single set of chromosomes

Question 8

Before cells can undergo mitosis, what two things must happen?

Answer 8

it must go interphase, to grow and produce proteins necessary for division.

S phase-the cell duplicates its chromosomes and ensures its systems are ready for cell division.

Question 9

What is Interphase? What are the steps and what happens in each step?

Answer 9

Interphase – Most of a cell’s life is spent in this phase

-G1 phase - Growth and normal metabolism

-S phase - DNA replicates and histone proteins are synthesized

-G2 phase - Protein synthesis increases in preparation for division

-M Phase- mitosis and cytokinesis

Question 10

What happens in mitosis?

Answer 10

prophase, prometaphase, metaphase, anaphase,
and telophase

Question 11

What happens in cytokinesis?

Answer 11

division of the cell cytoplasm to form two cells

Question 12

What is apoptosis?

Answer 12

programmed cell
death

Question 13

What happens during: Prophase?

Answer 13

-Chromosomes compact

• Duplicated chromosomes consist of a pair of identical sister chromatids

 Nuclear envelope begins to break down and nucleolus disappears

 Mitotic spindles form

Question 14

What is the mitotic spindle?

Answer 14

separates duplicated chromosomes

Question 15

What happens during: Prometaphase?

Answer 15

Begins when nuclear envelope
breaks down

-Chromosomes move toward cell’s midplane

-Cohesins dissociate from sister chromatid arms,
freeing them from one another

Question 16

What happens during: Metaphase?

Answer 16

All the cell’s chromosomes align
at the cell’s metaphase plate

Question 17

What happens during: Anaphase?

Answer 17

Begins as sister chromatids
separate into separate chromosomes that move toward opposite poles

Question 17

What happens during: Telophase?

Answer 17

Telophase - Chromosomes arrive at the poles and return to interphase-like conditions

 Chromosomes decondense by partially uncoiling

 A new nuclear envelope forms around each set of chromosomes

 Spindle microtubules disappear and nucleoli reorganize

Question 18

What is a cleavage furrow?

Answer 18

deepens and separates the cytoplasm (animal and fungal cells)

Question 19

How many cells result from mitosis? Are they haploid or diploid? Are they identical or not?

Answer 19

-2
-diploid
-yes

Question 20

Why is cytokinesis different in plants?

Answer 20

they have a cell wall so they use a cell plate to separate

Question 21

How many chromosomes do bacteria have?

Answer 21

1

Question 21

What do we call prokaryotic cell division / mitosis?

Answer 21

binary fission

Question 22

What is the region where the chromosome attaches to the inside of the cell membrane?

Question 23

What is the origin of replication?

Answer 23

a sequence from where replication starts and any piece of foreign DNA is linked to this sequence.

Question 24

What are plasmids?

Answer 24

dna in cytoplasm

Question 25

What is metastasis?

Answer 25

where the site of cancer spreads

Question 25

What are chromatids?

Answer 25

one of the two identical halves of a chromosome (/)

Question 26

What are homologous chromosomes (homologous pairs)?

Answer 26

paired chromosomes X

Question 26

What is the region of a chromosome that joins sister chromatids?

Answer 26

centromere

Question 27

What is Meiosis?

Answer 27

in organisms that reproduce sexually, sperm and egg have reduced chromosome number and zygote has full set  Produces haploid cells (gametes)

Question 28

What is the haploid number in humans?

Answer 28

23

Question 29

What is “crossing over”?

Answer 29

enchanging DNA

Question 29

What is synapsis?

Answer 29

the fusion of chromosome pairs at the start of meiosis.

Question 30

What is “independent assortment”?

Answer 30

the allele a gamete receives for one gene does not influence the allele received for another gene.

Question 31

What happens during: Meiosis I?

Answer 31

Homologous chromosomes align side by side, which results in association of four chromatids - Synapsis occurs (XX)

Question 32

What happens during: Meiosis II?

Answer 32

-Prophase 2 – chromosomes condense and nuclear membrane begins to break down -Metaphase 2 – sister chromatids meet at the equator -Anaphase 2 – sister chromatids separate -Telophase 2 – sister chromatids have reached opposite ends of the poles - Cytokinesis – cytoplasm divides

Question 33

How many cells result from meiosis? Are they haploid or diploid? Are they identical or not?

Answer 33

-4 -haploid cells -no

Question 34

What is spermatogenesis? Oogenesis?

Answer 34

- the process by which sperm cell production occur -“Oogenesis is the process of formation of female gametes.”