Chapter 7 Flashcards
(124 cards)
1
Q
diploid
A
two copies of every chromosome (2n), one from each parent
1
Q
rapid and effective reproduction that makes clones of the parent. any genetic variations are due to mutations or errors. prokaryotes do this (binary fission) and eukaryotes can do this too
A
asexual reproduction
1
Q
one copy of every chromosome (n=23 in people), one homolog from each pair. gametes.
A
haploid
1
Q
ori (origin)
A
region of chromosome. where replication starts
1
Q
diplontic life cycle
A
animals and plants life cycle, gametes are only haploid stage. then it fuses to form diploid in fertilization. all other stages and all cells are diploid.
1
Q
cell cycle
A
the time from one cell division to the next cell division. 2 phases in eukaryotes: interphase (long G1, S, G2) and M phase (mitosis and cytokinesis)
1
Q
metaphase
A
3rd phase of mitosis. chromosomes line up at midline (metaphase plate) of the cell
1
Q
point where genetic material is echanged between homologous chromosomes
A
chiasmata
1
Q
occurs during anaphase 1, it is a matter of chance as to which chromosomes (maternal or paternal) go to which daughter cell / gamete.
A
independent assortment
2
Q
fertilization
A
process where two haploid gamtes fuse to form a zygote during sexual reproduction
2
Q
replicates DNA. part of cell division. only occurs in S phase (synthesis)
A
replication
2
Q
interphase
A
part of cell cycle. in between rounds of mitosis. longest part. chromatin is not condensed (DNA loosely wrapped around protein histones). includes G1 (normal cell job), S (DNA replication), G2 (preparing for mitosis)
2
Q
astral microtubules
A
type of microtubules in spindle. interact with cell membrane and help keep poles apart
2
Q
4th phase of meiosis. separating homologous pairs into chromosomes that to opposite poles
A
anaphase I
2
Q
a meiosis error. if a homologous pair or chromatids do not separate at anaphase I or II. this causes aneuploidy
A
nondisjunction
3
Q
important for reproduction, growth and repair of tissues. 4 events: reproductive signal, replication, segregation and cytokinesis
A
cell division
4
Q
chromatid, sister chromatids
A
half of a chromosome. every chromosome has 2. this is a molecule of DNA. connected by centromere at center. made when chromosome is replicated in S phase
5
Q
centrioles
A
2 of these make up centrosomes. these are hollow tubes formed by microtubules
7
Q
1st phase of meiosis. can last a long time (decades in females, month in males). chromatin condenses. difference - homologous chromosomes pair up (synapsis). this forms a tetrad (4 chromatids). these homologs cross over at chiasmata
A
prophase I
9
Q
centrosome
A
in prophase, poles where chromosomes are moved to. one at each end of the cell
9
Q
chromosomes
A
condensed and compact chromatin that appear during prophase. they get wrapped tightly! composed of two chromatid
10
Q
region where chromatids are joined together
A
centromere
11
Q
cytokinesis
A
division of cytoplasm and separation of the two new cells. with a contractile ring. part of cell division. happens after mitosis in M phase
12
Q
interphase
A
long part of cell cycle. G1 (gap 1), S (DNA synthesis / DNA replicates) and G2 (gap 2)
12
minus end-drected motor protein at kinetochores. move chromosomes along microtubules towards poles by hydrolyzing ATP for energy or microtubules shortening
cytoplasmic dynein
13
centromere
region where chromatids are joined together
13
in prophase, poles where chromosomes are moved to. one at each end of the cell
centrosome
15
protein structures on centromere. microtubules attach here. important for moving chromosomes
kinetocore
16
type of microtubules in spindle. attach to kinetochore on chromatids to pull chromatids apart
kinetochore microtubules
16
anaphase I
4th phase of meiosis. separating homologous pairs into chromosomes that to opposite poles
16
error in meiosis. crossing over between non homologous chromosomes. one example of this is leukemia (if this happens in WBCs)
translocation
17
prophase I
1st phase of meiosis. can last a long time (decades in females, month in males). chromatin condenses. difference - homologous chromosomes pair up (synapsis). this forms a tetrad (4 chromatids). these homologs cross over at chiasmata
18
during sexual reproduction, two haploid gametes fuse to form this
zygote
18
crossing over
exchange of genetic information between homologous chromosomes. occurs at chiasmata
18
aneuplodiy
a meiosis error caused by nondisjunction. this is a lack or excess of chromosomes. e.g. Down syndrome (trisomy) or Turner syndrome (monosomy)
19
recombinant chromosomes
chromosomes that are part maternal and part paternal. causd by crossing over between homologous chromosomes in meiosis to increase genetic variation
20
region of chromosome. where replication starts
ori (origin)
21
meiosis
two nuclear divisions (but DNA is only replicated once). function is to go from 1 diploid cell to 4 haploid cells (2n to n). ensures each haploid has a full chromosome and generates diversity. produces gametes
22
somatic cells
body cells, not specialized for reproduction
23
this normally inhibits further progression in cell cycle (like from G1 to S). this is often inactivated in cancer cells which leads to uncontrolled cell division
retinoblastoma protein (RB)
25
2nd phase in mitosis. nuclear envelope breaks down. chromosomes (2 chromatids) attach to kinetochor microtubules
prometaphase
26
zygote
during sexual reproduction, two haploid gametes fuse to form this
28
process where two haploid gamtes fuse to form a zygote during sexual reproduction
fertilization
30
region of chromosome. where replication ends
ter (terminate)
32
division of cytoplasm and separation of the two new cells. with a contractile ring. part of cell division. happens after mitosis in M phase
cytokinesis
32
serve as poles, determine orientation of spindles. chromosomes are moved here. made of 2 hollow tubes called centrioles. duplicated in S phase in order to separate chromosomes.
centrosomes
34
5th phase of mitosis. clusters of chromosomes at either end of the cell, they decondense (to do its normal job in interphase). reform nuclear envelopes. end with 2 indentical daughter nuclei with identical genetic info
telophase
36
spindles
"machinery" that pulls chromosomes apart toward centrosome in prophase. these form between centrosomes. there are 3 types of microtubules in this: polar microtubles, astral microtubles and kinetochore microtubules
37
prometaphase I
2nd stage of meiosis. nuclear envelopre breaks down
38
cytoplasmic dynein
minus end-drected motor protein at kinetochores. move chromosomes along microtubules towards poles by hydrolyzing ATP for energy or microtubules shortening
39
mitosis
division of nucleus. how eukaryotic cells divide. chromosomes condense and wrap around proteins before this starts. chromosomes separate into 2 new nuclei using the cytoskeleton. 1 diploid cell produces 2 diploid cells. 5 phases: prophase, prometaphase, metaphase, anaphase, telophase
41
growth factors
these stimulate cell division and differentiation (become more specialized cells)
43
asexual reproduction
rapid and effective reproduction that makes clones of the parent. any genetic variations are due to mutations or errors. prokaryotes do this (binary fission) and eukaryotes can do this too
44
retinoblastoma protein (RB)
this normally inhibits further progression in cell cycle (like from G1 to S). this is often inactivated in cancer cells which leads to uncontrolled cell division
45
"machinery" that pulls chromosomes apart toward centrosome in prophase. these form between centrosomes. there are 3 types of microtubules in this: polar microtubles, astral microtubles and kinetochore microtubules
spindles
46
segregation
distribution of DNA into 2 new cells. part of cell division
48
the fusion of two specialized cells, gametes, that results in offspring with considerable genetic variation
sexual reproduction
49
gametes
specialized sexual reproductive cell (egg or sperm), form by meiosis. these are haploid. when they fuse they form a zygote which is diploid
50
anaphase
4th phase of mitosis. sister chromatids separate and are then called daughter chromosomes
52
passing this point means the cell will proceed with cell cycle and divide (no turning back). this point isin G1. this helps us prevent reproducing bad or mutated cells. cyclin and protein kinase signal this transition
restriction point (R) / G1-S transition
53
2nd stage of meiosis. nuclear envelopre breaks down
prometaphase I
54
type of microtubules in spindle. interact with cell membrane and help keep poles apart
astral microtubules
55
pair of matching chromosomes, made up of a chromosome from each of the parents
homologous pairs, homologs (individually)
56
specialized sexual reproductive cell (egg or sperm), form by meiosis. these are haploid. when they fuse they form a zygote which is diploid
gametes
56
chromatin
DNA wrapped loosely around protein histones. this is how it usually lives.
57
4th phase of mitosis. sister chromatids separate and are then called daughter chromosomes
anaphase
58
initiates cell division. part of cell division
reproduction signal
60
2 of these make up centrosomes. these are hollow tubes formed by microtubules
centrioles
61
two copies of every chromosome (2n), one from each parent
diploid
61
condensed and compact chromatin that appear during prophase. they get wrapped tightly! composed of two chromatid
chromosomes
62
chiasmata
point where genetic material is echanged between homologous chromosomes
64
1st phase in mitosis. DNA and chromosomes condense, centrosomes and spindles appear
prophase
65
metaphase I
3rd stage of meiosis, homologous pairs line up at midline
66
prometaphase
2nd phase in mitosis. nuclear envelope breaks down. chromosomes (2 chromatids) attach to kinetochor microtubules
67
exchange of genetic information between homologous chromosomes. occurs at chiasmata
crossing over
68
chromosomes that are part maternal and part paternal. causd by crossing over between homologous chromosomes in meiosis to increase genetic variation
recombinant chromosomes
70
these stimulate cell division and differentiation (become more specialized cells)
growth factors
71
restriction point (R) / G1-S transition
passing this point means the cell will proceed with cell cycle and divide (no turning back). this point isin G1. this helps us prevent reproducing bad or mutated cells. cyclin and protein kinase signal this transition
73
kinetochore microtubules
type of microtubules in spindle. attach to kinetochore on chromatids to pull chromatids apart
74
haploid
one copy of every chromosome (n=23 in people), one homolog from each pair. gametes.
74
centrosomes
serve as poles, determine orientation of spindles. chromosomes are moved here. made of 2 hollow tubes called centrioles. duplicated in S phase in order to separate chromosomes.
75
prophase
1st phase in mitosis. DNA and chromosomes condense, centrosomes and spindles appear
77
body cells, not specialized for reproduction
somatic cells
78
type of microtubules in spindle. keep poles at opposite end of the cell
polar microtubules
80
polar microtubules
type of microtubules in spindle. keep poles at opposite end of the cell
81
translocation
error in meiosis. crossing over between non homologous chromosomes. one example of this is leukemia (if this happens in WBCs)
82
genetic diversity
we get this from meiosis. processes that can lead to this: independent assortment, crossing over and translocation, and random selection
83
cell division
important for reproduction, growth and repair of tissues. 4 events: reproductive signal, replication, segregation and cytokinesis
83
reflects the nummber, size and banding pattern of an organism's condensed chromosomes. you can tell the gender (XX vs XY). e.g. humans have 23 chromosomes
karyotype
85
homologous pairs, homologs (individually)
pair of matching chromosomes, made up of a chromosome from each of the parents
86
half of a chromosome. every chromosome has 2. this is a molecule of DNA. connected by centromere at center. made when chromosome is replicated in S phase
chromatid, sister chromatids
87
the time from one cell division to the next cell division. 2 phases in eukaryotes: interphase (long G1, S, G2) and M phase (mitosis and cytokinesis)
cell cycle
88
a meiosis error caused by nondisjunction. this is a lack or excess of chromosomes. e.g. Down syndrome (trisomy) or Turner syndrome (monosomy)
aneuplodiy
89
ter (terminate)
region of chromosome. where replication ends
91
animals and plants life cycle, gametes are only haploid stage. then it fuses to form diploid in fertilization. all other stages and all cells are diploid.
diplontic life cycle
92
replication
replicates DNA. part of cell division. only occurs in S phase (synthesis)
93
we get this from meiosis. processes that can lead to this: independent assortment, crossing over and translocation, and random selection
genetic diversity
94
DNA wrapped loosely around protein histones. this is how it usually lives.
chromatin
95
sexual reproduction
the fusion of two specialized cells, gametes, that results in offspring with considerable genetic variation
97
independent assortment
occurs during anaphase 1, it is a matter of chance as to which chromosomes (maternal or paternal) go to which daughter cell / gamete.
98
division of nucleus. how eukaryotic cells divide. chromosomes condense and wrap around proteins before this starts. chromosomes separate into 2 new nuclei using the cytoskeleton. 1 diploid cell produces 2 diploid cells. 5 phases: prophase, prometaphase, metaphase, anaphase, telophase
mitosis
99
3rd stage of meiosis, homologous pairs line up at midline
metaphase I
100
distribution of DNA into 2 new cells. part of cell division
segregation
101
telophase 1
5th phase of meiosis. chromosomes gather into nuclei
102
3rd phase of mitosis. chromosomes line up at midline (metaphase plate) of the cell
metaphase
103
telophase
5th phase of mitosis. clusters of chromosomes at either end of the cell, they decondense (to do its normal job in interphase). reform nuclear envelopes. end with 2 indentical daughter nuclei with identical genetic info
105
kinetocore
protein structures on centromere. microtubules attach here. important for moving chromosomes
107
reproduction signal
initiates cell division. part of cell division
108
karyotype
reflects the nummber, size and banding pattern of an organism's condensed chromosomes. you can tell the gender (XX vs XY). e.g. humans have 23 chromosomes
109
non sex chromosomes
autosomes
110
nondisjunction
a meiosis error. if a homologous pair or chromatids do not separate at anaphase I or II. this causes aneuploidy
111
autosomes
non sex chromosomes
113
long part of cell cycle. G1 (gap 1), S (DNA synthesis / DNA replicates) and G2 (gap 2)
interphase
114
5th phase of meiosis. chromosomes gather into nuclei
telophase 1
115
two nuclear divisions (but DNA is only replicated once). function is to go from 1 diploid cell to 4 haploid cells (2n to n). ensures each haploid has a full chromosome and generates diversity. produces gametes
meiosis
116
part of cell cycle. in between rounds of mitosis. longest part. chromatin is not condensed (DNA loosely wrapped around protein histones). includes G1 (normal cell job), S (DNA replication), G2 (preparing for mitosis)
interphase
117
necrosis
cell is damaged and is starved for nutrients and oxygen so it bursts and dies
118
apoptosis
genetically programmed cell death. this happens because we want to get rid of old cells that are more prone to damage. this also happens toget rid of cells that we no longer need (webbing between fingers)
119
blebs
cells form this to break into fragments. part of apoptosis
120
caspases
enzymes that chews holes in the nuclear envelope to cause the cell to fall apart and die
121
cell is damaged and is starved for nutrients and oxygen so it bursts and dies
necrosis
122
genetically programmed cell death. this happens because we want to get rid of old cells that are more prone to damage. this also happens toget rid of cells that we no longer need (webbing between fingers)
apoptosis
123
cells form this to break into fragments. part of apoptosis
blebs
124
enzymes that chews holes in the nuclear envelope to cause the cell to fall apart and die
caspases
