Chapter 2: Mitosis and Meiosis

Question 1

viruses DO NOT

Answer 1

contain DNA

Question 2

an organisms DNA and genes are organized into

Answer 2

structures called chromosomes

Question 3

in eukaryotes genetic continuity of genetic material involves

Answer 3

mitosis and meiosis

Question 4

define chromatin

Answer 4

uncoiled chromosomes

Question 5

prokaryotic cells include

Answer 5

bacteria and archaea

Question 6

eukaryotic cells include

Answer 6

protists, plants, fungi, animals

Question 7

what allowed scientists to see the cell in its highly organized structure?

Answer 7

electron microscopy

Question 8

cell components which are directly or indirectly involved with genetic processes are

Answer 8

nucleolus

ribosome

centriole

Question 9

the nucleolus contains

Answer 9

• rRNA synthesized and initially asembled

- nucleolus organizer region (NOR)

Question 10

the NOR are portions of

Answer 10

DNA that encode for rRNA

Question 11

the smooth ER is the

Answer 11

site of lipid synthesis

Question 12

the rough ER is the site of

Answer 12

protein synthesis

Question 13

centrioles are

Answer 13

cytoplasmic bodies found in centrosomes

Question 14

centrioles organize

Answer 14

spindle fibers

Question 15

spindle fibers are composed of

Answer 15

microtubules consisting of tubulin protein

Question 16

chromosomes exists as _____ _____ in diploid organisms.

Answer 16

homologous pairs

Question 17

a metacentric chromosome has the centromere located in the ______ of the chromosome.

Answer 17

middle

Question 18

a submetacentric chromosome has the centromere located in the ______ of the chromosome.

Answer 18

between the middle and the end

Question 19

a acrocentric chromosome has the centromere located in the ______ of the chromosome.

Answer 19

close to the end

Question 20

a telacentric chromosome has the centromere located in the ______ of the chromosome.

Answer 20

at the end

Question 21

the haploid number is

Answer 21

-half of diploid number

Question 22

the haploid number constitutes

Answer 22

genome of species

Question 23

what is a karyotype?

Answer 23

number and visualization of chromosomes in a cell

Question 24

what is ploidy?

Answer 24

the number of sets of homologous chromosomes in the genome of a cell or an organism

Question 25

homologous chromosomes have identical

Answer 25

locus

Question 26

which type of chromosomes are not always homologous?

Answer 26

sex-determining chromosomes

Question 27

what is karyokinesis?

Answer 27

genetic material evenly divided into two nuclei

Question 28

what is cytokinesis?

Answer 28

cytoplasmic division

Question 29

the cell cycle is composed of

Answer 29

interphase and mitosis

Question 30

interphase is composed of

Answer 30

G1, S, G2

Question 31

S phase occurs in

Answer 31

nucleus where DNA is duplicated

Question 32

G1 and G2 occurs in

Answer 32

cytoplasm

Question 33

G0 phase is a point where

Answer 33

cells withdraw from cell cycle and enter a non-dividing but metabolically active state (happens in G1)

Question 34

most of the cell cycle is in

Answer 34

interphase

Question 35

the average human completes the cell cycle in

Answer 35

about 16 hours

Question 36

what are the discrete stages of mitosis

Answer 36

``` prophase prometaphase metaphase anaphase telophase ```

Question 37

describe what happens during prophase

Answer 37

chromosomes coil up and condense; centrioles divide and move apart

Question 38

describe what happens during prometaphase

Answer 38

chromosomes move to metaphase plate of cell due to spindle fibers bonding to kinetochores and moving the chromosomes

Question 39

what is cohesion?

Answer 39

a protein complex that holds sister chromatids together

Question 40

what enzyme degrades cohesion?

Answer 40

separase

Question 41

what is shugoshin?

Answer 41

"guardian spirit" that protects cohesion at the centromere while chromosomes are lining up on the metaphase plate

Question 42

describe what happens during metaphase

Answer 42

centromeres of chromosomes are aligned at the metaphase plate

Question 43

describe what happens during anaphase

Answer 43

disjunction occurs; chromosomes migrate to opposite poles

Question 44

what are the 3 things that need to happen for disjunction to be successful?

Answer 44

1. shugoshin is degraded 2. cohesion is cleaved 3. sister chromatids are pulled to opposite ends of the cells

Question 45

describe what happens during telophase

Answer 45

- chromosomes uncoil - nuclear envelope reforms - spindle fibers disappear - nucleolus reforms

Question 46

division of the cytoplasm is known as

Answer 46

cytokinesis

Question 47

what do kinases serve as?

Answer 47

"master control" molecules

Question 48

what binds with kinases?

Answer 48

cyclins

Question 49

what two proteins activate cellular activity

Answer 49

kinases and cyclin

Question 50

the 3 major checkpoints are checked by? where do these checkpoints occur?

Answer 50

- master control molecules (kinases) | - G1, G2, M

Question 51

meiosis maintains

Answer 51

genetic continuity from gen. to gen.

Question 52

meiosis gives rise to genetic variation by

Answer 52

crossing over independent assortment

Question 53

meiosis I is known as the

Answer 53

reductional division

Question 54

meiosis II is known as the

Answer 54

equational division

Question 55

where does crossing over occur?

Answer 55

chiasma (prophase I)

Question 56

what is terminalisation?

Answer 56

when centromeres attach to spindles and nuclear envelope breaks down

Question 57

disjunction is when

Answer 57

half of each tetrad is randomly pulled to opposite poles

Question 58

spermatogenesis begins with

Answer 58

spermatogonium germ cell

Question 59

the spermatogonium becomes

Answer 59

primary spermatocyte

Question 60

primary spermatocyte undergoes mitotic division and produces

Answer 60

haploid secondary spermatocytes

Question 61

secondary spermatocytes undergo

Answer 61

meiosis II

Question 62

oogenesis begins with

Answer 62

oogonium

Question 63

the oogonium enlarges and becomes the

Answer 63

primary oocyte

Question 64

what are the two characteristics to the meiotic division that produce daughter cells during oogenesis?

Answer 64

- receive equal amounts of genetic material | - do NOT receive equal amounts of cytoplasm

Question 65

what receives the bulk of cytoplasm?

Answer 65

the secondary oocyte

Question 66

what is a polar body?

Answer 66

cell with little to no cytoplasm

Question 67

secondary oocyte undergoes secondary division and produces

Answer 67

an ootid and a 2nd polar body

Question 68

secondary division is completed

Answer 68

after fertilization

Question 69

human chromosome 1 is made up of how many nucleotides and genes?

Answer 69

-about 250 million nucleotides 2,000 genes