Cell Division

Question 1

When a cell is not dividing, each chromosome exists in a single copy called a

Answer 1

chromatid

Question 2

When the cell is preparing to divide, each chromosome must be replicated so that it contains –

Answer 2

2 chromatids (sister chromatids)

Question 3

each chromosome has a compressed region

Answer 3

centromere

Question 4

When the chromosomes replicate the – stay attached to each other at the centromere

Answer 4

sister chromatids

Question 5

mitosis occurs in most cells except for –, –, –

Answer 5

gametes and mature never and muscle cells in animals

Question 6

during G1, the parent cell is growing larger and is adding – and replicating –

Answer 6

cytoplasm, organelles

Question 7

first gap phase of the cell cycle

Answer 7

G1 stage

Question 8

phase of DNA synthesis when the chromosomes are all being replicated

Answer 8

S stage

Question 9

Once – is complete, each chromosome will consist of 2 sister chromatids connected at the centromere

Answer 9

S stage

Question 10

second gap phase

Answer 10

G2

Question 11

During G2 the cell will continue to – and make final preparations for cell division

Answer 11

grow in size

Question 12

mitosis occurs in this phase

Answer 12

M

Question 13

division of the cytoplasm at the end of the M phase is

Answer 13

cytokinesis

Question 14

interphase = G1, S, G2

Answer 14

preparation for cell division

Question 15

examples of cells that lose the ability to undergo the cell cycle and thus cannot divid

Answer 15

mature human nerve and muscle cells

Question 16

cells without the ability to divide are in the – phase where division will never resume

Answer 16

G0

Question 17

chromosomes are located in the –

Answer 17

nucleus

Question 18

prior to division, the chromosomes are not condensed and thus are –

Answer 18

not visible

Question 19

leaving the chromosomes in an uncondensed state makes it easier to copy the DNA but makes the chromosomes very –

Answer 19

stringy and fragile

Question 20

once the DNA is replicated, the chromosomes must condense so that they are not – as they are divided up into the two daughter cells

Answer 20

broken

Question 21

chromosome condensation occurs, making the chromosome visible

Answer 21

prophase

Question 22

During prophase, the – present in the cello replicate and move to opposite ends of the cell

Answer 22

centrioles

Question 23

When the centrioles reach the poles of the cell, they begin to produce –

Answer 23

spindle apparatus

Question 24

the spindle apparatus consist of spindle fibers that radiate outward forming –

Answer 24

asters

Question 25

spindle fibers are made of -- that will ultimately attach to each chromosome at the kinetochore

Answer 25

microtubules

Question 26

kinetochore (protein structure) appears at the -- of each chromosome

Answer 26

centromere

Question 27

nuclear envelope and lamina is broken down by phosphorylation of the nuclear pore proteins and lamins

Answer 27

prometaphase

Question 28

once the -- breaks down, the spindle microtubules will attach to the chromosomes by binding to the kinetochore

Answer 28

nucleus

Question 29

chromosomes align down the center of the cell

Answer 29

metaphase

Question 30

there is a checkpoint in this phase

Answer 30

metaphase

Question 31

centromere spits, allowing each chromatid to have its own centromere

Answer 31

anaphase

Question 32

during anaphase, the chromatids can be separated and are pulled towards

Answer 32

opposite poles

Question 33

chromatids are moved to opposite poles by -- of the kinetochore microtubules

Answer 33

depolymerization

Question 34

nuclear pore proteins and lamina are dephosphorylated in this phase because the spindle apparatus is no longer needed

Answer 34

telophase

Question 35

during telophase, the -- and -- reform around each set of chromosomes

Answer 35

nuclear envelope and lamina

Question 36

in animal cells, a -- forms that pinches the cells apart from each other

Answer 36

cleavage furrow

Question 37

in plant cells, a -- made of cellulose divides the two daughter cells

Answer 37

cell plate

Question 38

the end result of mitosis, is two daughter cells ready to begin -- of their cell cycle

Answer 38

interphase

Question 39

crossing over occurs in

Answer 39

prophase I

Question 40

crossing over = homologous pairs of chromosomes associate and twist together in --

Answer 40

synapsis

Question 41

the result of crossing over is two replicated chromosomes or a total of four chromatids called a

Answer 41

tetrad

Question 42

T or F: crossing over can occur in more than one location and can unlink genes that were previously linked on the same chromosome

Answer 42

true

Question 43

crossing over is an important source of genetic diversity, creating combinations of -- that were not seen previously

Answer 43

alleles

Question 44

in metaphase of mitosis, chromosomes align -- down the center of the cell

Answer 44

single file

Question 45

in metaphase I of meiosis, the chromosomes align as -- down the center of the cell

Answer 45

pairs

Question 46

law of independent assortment

Answer 46

the alignment of each member of the homologous pair during metaphase I is random giving a unique combination of maternal and paternal alleles

Question 47

during anaphase I, -- will separate from each other and be pulled to the poles of the cells

Answer 47

homologous pairs

Question 48

the separation during anaphase I is referred to as --

Answer 48

disjunction

Question 49

at the end of telophase I, each daughter cell is genetically unique and contains -- number of the chromosomes of the parent cell

Answer 49

half

Question 50

at the end of telophase I, the chromosomes are still in their -- form, consisting of two chromatids

Answer 50

replicated

Question 51

-- split the chromatids present in the daughter cells produced during meiosis I

Answer 51

meiosis II

Question 52

the events in this phase does not occur in all species

Answer 52

prophase II

Question 53

metaphase II

Answer 53

chromosomes align down the center of the cell

Question 54

anaphase II

Answer 54

sister chromatids are separated and move toward the poles of the cell

Question 55

telophase II

Answer 55

nuclear envelopes reform and cytokinesis occurs to produce daughter cells

Question 56

at the end of meiosis II, each daughter cell has a -- copy of each chromosome

Answer 56

single