mitosis

Question 1

genome

Answer 1

complete set of genetic material in a cell

Question 2

exceptions to individual’s cells having same genome

Answer 2

sperm/egg and cells that lack DNA

Question 3

karyotype

Answer 3

individual’s full set of chromosomes

Question 4

chromosome

Answer 4

1 continuous strand of DNA + associated protein

Question 5

chromosome structure

Answer 5

linear in eukaryotes

circular in prokaryotes + other structural differences

Question 6

how many pairs in humans

Answer 6

22 pairs autosomal chromosomes, 1 pair sex

Question 7

gene

Answer 7

segment of DNA that often codes for a specific protein -> certain function

Question 8

what are a point on genes called

Answer 8

locus

Question 9

what determines protein

Answer 9

order of nucleotides

Question 10

allele

Answer 10

diff. versions of a gene that code for the same trait

Question 11

diploid cells have what and what is 2n in humans

Answer 11

full set of pairs of homologous chromosomes
2n=46

Question 12

haploid cells have what

Answer 12

only have each of one chromosome

Question 13

what are haploid and what is n in humans

Answer 13

human sperm and egg (also some entire organisms)
n=23

Question 14

why do cells need to divide

Answer 14

reproduction, growth/development, normal tissue renewal

Question 15

what must cell do before any division

Answer 15

grow, duplicate DNA (interphase)

Question 16

what are identical copies referred to as

Answer 16

chromatids

Question 17

where is vast majority of cell life spent

Answer 17

interphase or in non dividing state - lots of variation in amount of division

Question 18

mitosis cell division in eukaryotes does what

Answer 18

makes a copy of the cell, with same amount of DNA (splits identical chromatids)

Question 19

what does meiosis do in eukaryotes and why

Answer 19

splits up chromatids AND homologous chromosomes (1/2 DNA) for sexual reproduction

Question 20

what is used in asexual reproduction

Answer 20

mitosis

Question 21

downside of sexual reproduction

Answer 21

takes energy to produce eggs/sperm and find mate

Question 22

advantage of sexual reproduction

Answer 22

increases genetic diversity and generates new combos of alleles

Question 23

where are chromosomes normally condensed

Answer 23

only during division

Question 24

before cell division, interphase does what

Answer 24

produces copies of each chromosome (sister chromatids)

Question 25

what joins sister chromatids

Answer 25

cohesion proteins

Question 26

how does mitosis divide the nucleus

Answer 26

by dividing sister chromatids to two daughter nuclei w/ identical # of chromosomes and genes/alleles

Question 27

what usually follows

Answer 27

cytokinesis which divides cytoplasm into two daughter cells

Question 28

what structures to watch during mitosis

Answer 28

chromatids, centrosomes/cytoskeleton, nuclear envelope

Question 29

how to be able to pull apart chromatids

Answer 29

cytoskeleton - organized by centrosomes in animals and other eukaryotes

Question 30

when are chromosomes replicated

Answer 30

interphase

Question 31

how to access chromatids

Answer 31

dissolve nuclear membrane

Question 32

prophase (first step)

Answer 32

chromosomes condense and early spindle apparatus (structural elements) begin to form

Question 33

prometaphase (second step)

Answer 33

nuclear envelope disintegrates and chromosomes attach to spindle apparatus (microtubules contact at kinetochores)

Question 34

metaphase (third step)

Answer 34

chromosomes line up along center of cell with one chromatid on each side of center (metaphase plate)

Question 35

anaphase (fourth step)

Answer 35

sister chromatids pulled apart into daughter chromosomes and are pulled to opposite poles of spindle apparatus (now considered separate chromosomes)

Question 36

telophase (last step)

Answer 36

reversal of first two steps (chromosomes uncoil, structural elements go back to normal, nuclear membrane reforms)

Question 37

cytokinesis

Answer 37

cleavage furrow forms (if animal cell) of contractile proteins actin and myosin (ring causes plasma membrane to pinch in)

Question 38

spindle apparatus

Answer 38

microtubules attached to kinetochores (middle protein complexes) of each chromatid push/pull chromosomes into position at metaphase plate

Question 39

what happens to microtubules once cohesions cleaved

Answer 39

kinetochore microtubules shorten, pulling chromosomes towards centrosomes (anaphase)

Question 40

what do plant cells use for cytokinesis (diff. b/w animal cells)

Answer 40

cell plate uses spindle microtubules to direct vesicles w/ cell wall components

Question 40

what do motor proteins do

Answer 40

motor proteins on overlapping non-kinetochore microtubules push two ends of cell apart

Question 41

what does bacteria use instead of mitosis

Answer 41

binary fission that has circular chromosomes and no nucleus

Question 42

will pass G1/S checkpoint if

Answer 42

cell size is adequate, sufficient nutrients, social signals present, DNA undamaged

Question 43

will pass G2/M checkpoint if

Answer 43

chromosomes have replicated properly, DNA is undamaged, activated M phase-promoting factor (MPF) is present

Question 44

will phase M-phase checkpoints if

Answer 44

chromosomes have attached to spindle apparatus, chromosomes have properly segregated and MPF is absent

Question 45

how can stimulation control mitosis

Answer 45

by signals from other cells and/or by signals from within the cell (ex. MPF which initiates cell division can be injected to jumpstart division for cell in interphase)

Question 46

what is MPF composed of

Answer 46

cyclin and Cdk

Question 47

when does cyclin concentration peak and what is it

Answer 47

MPF's cyclin (regulatory protein) concentration peaks at end of interphase/beginning of M phase

Question 48

what is Cdk

Answer 48

kinase that phosphorylates multiple proteins involved in onset of cell division (to start M phase)

Question 49

what does MPF do

Answer 49

initiate mitosis

Question 50

what else regulates G1 checpoint

Answer 50

cyclin/kinase dimer: other cells can produce growth factors, a form of social signals b/w cells stimulate cyclin and E2F production which results in release of E2f and passes checkpoint leading to DNA duplication