Cell Division and Cell Cycle

Question 1

prokaryote and single celled euk - reproduction

Answer 1

binary fission

Question 2

what do multicellular euk divide for? (4-5)

Answer 2

• tissue growth
• damage tissue repair
• mitosis: reproduction
• meiosis: requires specialized cells = GERM cells
  -> specialized division to produce sex cells = GAMETES

Question 3

what is G0?

Answer 3

some cells never leave interphase - stop dividing

Question 4

G1, S, G2, M steps

Answer 4

G1: cell grows, normal metabolism, organelles duplicated, prep for S (if needed)
S: DNA replication, chromosome duplication (S=synthesis)
G2: cell grows, prepares for mitosis, DNA is “pseudo-4N”
M: mitosis (karyokinesis): prophase, prometaphase, metaphase, anaphase, telophase, cytokinesis

Question 5

what is karyokinesis?

Answer 5

division of a cell nucleus during mitosis

Question 6

which ones keep growing throughout G1, S, G2?
(protein/RNA/DNA)

Answer 6

protein and RNA
(DNA only replicates during S phase)

Question 7

homologous chromosomes are from?

Answer 7

one from mother
one from father

Question 8

total # of diff alleles for any given gene is?

Answer 8

> 1
NOT related to number of copies of that allele found in genome

Question 9

what happens in prometaphase?

Answer 9

chromosomes start to try to align

Question 10

which specific proteins (2) whose activity fluctuates during cell cycle STOP cell cycle to make assessment (CHECKPOINTS)?

Answer 10

• cyclins
• cyclin-dependent kinases

Question 11

purpose of checkpoints

Answer 11

• energy and resources are saved (don’t want damaged copy)
• internal control - through internal signals (ex. kinetochores not attached to spindle fibers, delay anaphase) - can be corrected
• external control (ex. growth factors, food)

Question 12

checkpoints (4)

Answer 12

1. G1 checkpoint: (before S phase)
   - cell growth
   - environment
2. S checkpoint (during S phase)
   - DNA replication
3. G2 checkpoint (entering mitosis)
   - DNA replication
   - environment
   - cell growth
4. Metaphase checkpoint (exit mitosis)
   - are chromosomes aligned on spindle?

Question 13

mass of cell must ___ to provide material for daughter cells

Answer 13

double

Question 14

how to preserve info while making it variable?

Answer 14

meiosis

Question 15

sexual reproduction: (2 steps)

Answer 15

1. production of special reproductive cells, or gamete (1n)
2. fusion of gametes (fertilization) - zygote (2n)

Question 16

gametes produced in specialized tissues (diploid germ cells) through ____ (2n -> n) cell division = meiosis

Answer 16

reductional

Question 17

what is relationship of germ cell to gametes?

Answer 17

precursor

Question 18

vertical gene transfer means?

Answer 18

genetic info from parent -> offspring

Question 19

horizontal gene transfer?

Answer 19

DNA moves between organelles in one organism (mitochondrial DNA -> nucleus)

Question 20

which organisms have life cycle with sporophyte and gametophyte?

Answer 20

plants and some algae

Question 21

which organisms can live as a haploid multicellular organism for a while?

Answer 21

plants and some algae
most fungi and some protists

Question 22

which organisms can make gametes through mitosis?

Answer 22

plants and some algae
most fungi and some protists

Question 23

number of possible new combinations of chromosomes for a species is 2^n

what is n?

Answer 23

n = haploid # of chromosomes for species

Question 24

pseudo 2n during?

Answer 24

start of meiosis II, end of meiosis I

Question 25

difference between meiosis I and meiosis II

Answer 25

meiosis I - chromosome segregation
meiosis II - chromatid segregation

Question 26

isogamy meaning

Answer 26

same gamete size

Question 27

anisogamy meaning

Answer 27

diff gamete sizes

Question 28

hermaphrodite meaning

Answer 28

both sets of reproductive organs

Question 29

monoecious meaning

Answer 29

like hermaphrodites but only for plants

Question 30

sexually polymorphic meaning

Answer 30

either male/female/other sexes

Question 31

parthenogenesis

Answer 31

some lizards produce diploid eggs asexual

Question 32

plants: hermaphrodites vs monoecious

Answer 32

hermaphrodite: male and female parts in same flower
monoecious: separate male and female flowers in same plant