Photosynthesis, meiosis, mitosis, genes Flashcards
(122 cards)
1
Q
convert light energy to chemical energy as ATP and NADPH.
A
light reactions
2
Q
occur in the thylakoid membrane
A
light reactions
3
Q
uses ATP and NADPH plus CO2 to produce carbohydrates. converts carbon dioxide into metabolically active compounds
A
carbon-fixation reactions
4
Q
occur in the stroma
A
carbon-fixation reactions
5
Q
pigment molecules are arranged in light-harvesting complexes
A
antenna systems
6
Q
light energy is captured in ________ and transferred to __________
A
light harvesting complexes, reaction centers
7
Q
when a pigment molecule absorbs a photon,
A
the excited state is unstable and the energy is quickly released
8
Q
the energy released from the pigment molecule is absorbed by other pigment molecules and passed to ___
A
chlorophyll in a reaction center
9
Q
in the reaction center, the light energy is converted to _______
A
chemical energy
10
Q
excited chlorophyll å molecule (ChI+) gives an electron to an accepter
A
redox reaction, chlorophyll is oxidized to Chl+, the accepter molecule is reduced
11
Q
electron accepter is first in chain of carriers in thylakoid membrane,
A
photosynthesis transport
12
Q
ATP is formed by a chemiosmatic mechanism
A
photophosphorylation
13
Q
H+ is transported across the thylakoid membrane into the lumen, creating
A
an electrochemical gradient
14
Q
water _______ creates more H+ in the lumen and NADP+ ______ removes H+ in the stroma; contributing to the H+ gradient
A
oxidation; reduction
15
Q
high H+ concentration in the lumen drives H+ back into the stroma through
A
ATP synthase channels
16
Q
reduces NADP+ to NADPH
A
photosystem I
17
Q
produces ATP through ATP synthase
A
photosystem II
18
Q
uses photosystem I and electron transport to produce ATP instead of NADPH
A
cyclic electric transport
19
Q
3 main stages of calvin cycle
A
carbon fixation
reduction
regeneration
20
Q
CO2 incorporated in 5-carbon (RuBP) by the enzyme rubisco (6-carbon splits to 2 molecules of 3-PGA)
A
carbon fixation
21
Q
each 3-PGA gets phosphate from ATP (substrate level phosphorylation) these are reduced to NADPH and become G3P
A
reduction
22
Q
some G3P molecules make glucose, others are recycled to regenerated 5-carbon, RuBP, which is necessary for carbon fixation
A
regeneration
23
Q
(4 carbons) no photorespiration on hot days (have the advantage on hot days)
A
C4 plants
24
Q
in mosophyll cells, PEP carboxylase catalyzes the reaction of CO2 and PEP to form oxaloacetate, which is converted to malate,
- malate diffuses to bundle sheath cells, and is decarboxylated to pyruvate and CO2. pyruvate goes back to mesophyll cells to regen. PEP
- CO2 enters the calvin cycle
A
C4 plants
25
initial carbon-fixing enzyme is NOT rubisco
- ATP has to be spent to move intermediates back and forth across membrane
C4 plants
26
stomata are open at night and closed during the day to conserve water
Crassulacean acid metabolism (CAM plants)
27
in CAM plants, CO2 is fixed by PEP carboxylase and malate is stored in vacuoles
at night
28
in CAM plants, malate moves to chloroplasts and is carboxylated, the CO2 goes to Calvin cycle
during the day
29
4 events that characterize cell division
cell division signals
DNA replication
DNA segregation
cytokinesis
30
have "ori" and "ter" regions
DNA
31
in prokaryotes, ___________ are external factors: nutrient concentration and environment
cell signals
32
have 1 chromosome; occurs as DNA moves through a "replication complex" of proteins near the center of the cell
DNA replication in prokaryotes
33
"ori" regions move to opposite ends of the cell, segregating the daughter chromosomes
DNA segregation in prokaryotes
34
cell membrane pinches in; protein fibers form a ring, new cell wall material synthesize
Cytokinesis in prokaryotes
35
division may not always occur in ____
eukaryotes
36
related to the needs of the entire organism
cell division signals in eukaryotes
37
more than 1 chromosome, starts at many origins on chromosome; occurs in S in the cell cycle
DNA replication in eukaryotes
38
occurs through mitosis; separates newly replicated chromosomes into 2 genetically identical nuclei-- one copy of each chromosome in each cell
DNA segregation in eukaryotes
39
happens differently in animal and plant cells
cytokinesis in eukaryotes
40
results in reproduction of the entire single-celled organism
- begins with cell division signals, usually external factors
binary fission
41
phases a cell passes through to produce daughter cells by cell division
cell cycle
42
G1, S, G2; duration varies.
-cell nucleus is visible, typical cell function occur including replication
-everything but mitosis
interphase
43
in this phase, chromosomes are unreplicated; duration: minutes to year
- ends with signal
G1
44
in this phase, DNA replicates; sister chromatids stay together until mitosis
S phase
45
in this phase, cell prepares for mitosis by synthesizing structures that move chromatids to opposite ends
G2
46
in this phase, mitosis and cytokinesis happen; nuclear division
M phase
47
enzymes that catalyze transfer of phosphoric group from ATP to protein
- changes shape and function of the protein
protein kinases
48
controls G1 to S transition which is the restriction point (R)
- always present
Cyclin Dependent Kinases (CDK)
49
binds to CDK and changes shape (alloseric regulation), exposing active site
cyclin
50
prevents cell from leaving G1; inhibits cell cycle
retinoblastoma protein (RB)
51
catalyzes phosphorylation of RB, inactivating RB by changing shaper and no longer blocks the cell cycle
G1 cyclin-CDK
52
CDK's must be regulated to progress cycle and cell division (regulated by absence or presence of cyclins)
CDK regulation
53
centrosomes move to opposite ends of nuclear envelope; microtubules extend from centrosomes and form on the spindle
- chromosomes start out loose, but condense to be more compact and visible
-kinetichores form on chromatids to act as attachment point
prophase
54
conain motor proteins and are attachment points for microtubules
kinetichores
55
-nuclear envelope dissolves
-microtubules connect kinetichores on each sister chromatid to opposite centrosomes
prometaphase
56
contromeres line up at equator of cell, midway between the centrosomes
metaphase
57
chromatids separate
-new daughter chromosomes move toward the poles
-kinetichore microtubules shorten; centrosomes move apart
-M phase cyclin-CDK controls movement of sister chromatids
-APC activates separase
anaphase
58
separation of sister chromatids is controlled by ________
M phase Cyclin-CDK
59
protein that holds chromatids together
cohesin
60
organelles that organize the microtubules in animal cells;
-determine the differentiation of the mitotic spindle and move sister chromatids apart
centrosomes
61
separase ________ cohesin bonds
hydrolyzes
62
_________ activates separase
anaphase promoting complex (APC)
63
daughter chromosomes reach the poles
-nuclear envelopes reform, and chromosomes decondense
telophase
64
division of the cytoplasm
cytokinesis
65
vesicles from the golgi apparatus appear among the plane of cell division; fuse together to form new cell wall
cytokinesis in plants
66
cell membrane pinches between nuclei
- ring of microfilaments form; proteins contract and pinch cell in two
cytokinesis in animals
67
based on mitosis
-singe-celled organism reproduces itself with each cell cycle (some multicellular)
asexual reproduction
68
offspring are not identical to parents
-gametes are created by meiosis; each parent contributes one gamete
- gametes and offspring differ genetically from each other and parents
sexual reproduction
69
body cells not specialized for reproduction: divide by mitosis
- each __________ has homologous pairs of chromosomes with corresponding but not identical genes
-gametes contain only one set of chromosomes-- one homolog of each pair
somatic cells
70
chromosome number; one copy of each pair
haploid (n)
71
fertilization: 2 haploid gametes fuse to form
diploid zygote
72
2 copies of each chromosome
diploid (2n)
73
DNA is loose, chromosomes begin migrating to opposite poles
early prophase I; meiosis I
74
DNA condenses; the 4 chromatids from each homologous pair form a tetrad (come together)
mid-prophase I; meiosis I
75
crossovers occur between non-siser chromatids at chiasmata to form a recombinant chromosome
late prophase I-prometaphase; meiosis I
76
pairs of homologous chromosomes line up on opposite sides of metaphase plate
metaphase I; meiosis I
77
the pairs of homologous chromosomes separate to different daughter cells
anaphase I; meiosis I
78
chromosomes are at opposite ends of cell
-DNA decondenses
-cytokinesis finishes cell division
-end of meiosis I: 2 haploid cells
telophase I; meiosis I
79
chromosomes recondense after brief interphase; DNA does not replicate
prophase II; meiosis II
80
contromeres of sister chromatids line up across metaphase plates of cells
metaphase II; meiosis II
81
sister chromatids separate and move to opposite poles
- independent assortment of recombinant chromatids contribute to genetic diversity
anaphase II; meiosis II
82
chromosomes gather into nuclei and cells divide
telophase II; meiosis II
83
each of 4 cells have nucleus with haploid number of unreplicated chromosomes
products of meiosis I and II
84
exchange of genetic material between non-sister chromatids at the chiasmata
crossing over
85
crossing over results in ___________ and increases genetic variability of products
recombinant chromatids
86
hereditary determinants blend in the zygote
-once mixed, can not be separated
blending inheritance
87
hereditary determinants are distinct units (particles) that remain intact when gametes fuse
particulate inheritance
88
cross parental varieties with contrasting traits for a single character
monohybrid crosses
89
mendel's results clearly supported __________ hypothesis because ___________
particulate inheritance; you can pick out which one is different
90
the trait that occurs in F1 that is more abundant in F2
dominant trait
91
may be mutated and no longer expressed, or encode non-functional proteins
recessive alleles
92
the two copies of a gene separate during gamete formation
- each gamete receives only one copy
-mendel's work was validated because alleles of a gene segregate as chromosomes separate during Meiosis I
mendel's first law- the law of segregation
93
copies of different genes assort independently
-chromosomes segregate independently during formation of gametes, and so do any two genes located on separate chromosome pairs
mendel's second law- independent assortment
94
F1 individuals are crossed with homozygous recessive individuals
test crosses
95
cross true-breeding individuals differing in 2 characteristics
dihybrid cross
96
observable properties of an individual resulting from both genetic and environmental factors
phenotype
97
2 alleles that are the same (RR, rr)
homozygous
98
2 different alleles (Rr) one may be dominant (R) other may be recessive (r)
heterozygous
99
family trees that show the occurance of phenotypes in several generations of related individuals
pedigrees
100
pedigrees can be used to determine whether a rare allele is _______ or _______
dominant; recessive
101
every affected person has an affected parent; about 1/2 offspring of an affected parent are also affected
rare dominant allele
102
affected people can have 2 parents who are not affected; about 1/4 of children whose parents are both heterozygous
rare recessive alleles
103
alleles are neither dominant nor recessive--heterozygotes have intermediate phenotypes (F2 generation, original phenotypes "reappear"; alleles didn't "blend")
incomplete dominance
104
alleles produce phenotypes that are both present in the heterozygote
codominance
105
one allele has multiple phenotypic effects
pleiotropic
106
phenotypic expression of one gene is influenced by another gene (allele A isn't expressed unless allele B is expressed)
epistasis
107
due to both genes and environment (ex: height)
quantitative variation
108
mendel's pea characters were discrete and _____
qualitative
109
specific position on a chromosome
locus
110
the chromosomal regions that together determine such complex characters; can contain one or several genes
quantitative trait loci
111
the process by which light energy is converted to chemical energy in sugars
photosynthesis
112
when a photon hits a molecule, it can...
bounce off
pass through
be absorbed
113
uses 2 photosystems
photon hits pigment in PSII and electron is energized
energy is passed inward from pigment to pigment until it reaches reaction center
reaction center chlorophylls electron s boosted to a high energy level
noncyclic electron transport
114
2nd stage of photosynthesis
fixes CO2 into a usable form
calvin cycle
115
composed of controsomes and microtubules
mitotic spindle
116
observable physical feature (seed shape)
character
117
form of a character (round or wrinkled)
trait
118
stable, inherited changes in genetic material
mutations
119
proportion of individuals with a certain genotype that show the phenotype
penetrance
120
degree to which genotype is expressed in an individual
expressivity
121
2 nuclear divisions occur in _________
meiosis
122
