Biology Test 3 questions
The phase of the cell cycle that immediately follows GI is ________ phase; this is when the cell ____________
S; replicates the DNA
During photosynthesis, electrons from ________ are used to fix _____________
chlorophyll; CO2
Which of the following describes the proper sequence of steps in the breakdown of glucose to make ATP during cellular respiration
glycolysis -> conversion of pyruvate to Acetyl-CoA -> citric acid (Krebs) cycle -> generation of the proton motive force -> oxidative phosphorylation
A cell in the G1 portin of the cell cycle
has half as much DNA as a cell in G2
A cell in the G2 portion of the cell cycle
has twice as much DNA as in a cell in G1
CAM plants only open their stomata to sequester CO2 at night. Why?
to prevent water loss
How many times does the citric acid (Krebs) cycle turn per molecule of glucose used?
two
Which wavelengths are most effective at driving photosynthesis?
blue and red
In a cross between two homozygotes, one recessive and one dominant, what percentage of their offspring would be heterozygous?
100%
After meiosis II is complete, the resulting cells are
1n and 1C
If an organism is heterozygous for two traits that are linked, how many different genotypes are possible in its gametes? Assume that no crossing over occurs
2
The haploid number of human chromosomes is
23
A man and a woman both of normal pigmentation but both have one parent who is albion. Albinism is an autosomal recessive trait. What is the probability that their first child will be an albino?
25%
In tigers, a recessive allele causes a white tiger (virtual absence of fur pigmentation). If two phenotypically normal tigers that are heterozygous at this recessive gene are mated, what percentage of their offspring are expected to be white?
25%
Down syndrom due to trisomy 21 occurs when an abnormal gamete is formed with ___ copies of chromosome 21 and thus a zygote receives 3 copies of chromosome 21. It is usually caused by _______________
2; non-disjunction
A cell with haploid number of 16 will have _______ total chromosomes, ______________ homologous pairs of chromosomes, and form ____________ tetrads during meiosis I
32; 16;16
If a mother who is an unaffected carrier for an X linked disease has a son with a father who is disease free, what is the probability that their son will express the disease
50%
The horse, equus caballus, has 32 pairs of chromosomes; the donkey (equus asinus) has 31 pairs of chromosomes. How many chromosomes would be expected in the somatic (non-gametic) tissue of the mule, which is a hybrid offspring produced when a horse and a donkey mate?
63
If Lisa belongs to blood group Type O she could not possibly have the following set of parents
AB mother and B father
The synthesis of organic carbon-containing molecules in the light-independent reactions of photosynthesis consumes
ATP, NADPH and CO2
The light dependent reactions of photosynthesis harness the energy from sunlight to make
ATP, NADPH, but NOT CO2
The g+gene is located on the X chromosome; the wild-type allele is dominant, and the mutant allele (g) is recessive. You cross a wild type male fly with a mutant female fly. Which one of the following would be expected?
All females wild type, all males mutant
Both mitochondria and chloroplasts have each of the following items except one of the items. Which item is in only one organelle but not in both organelles?
Calvin cycle
Which of the following is not a condition that is assessed during the G1 checkpoint?
Completion of DNA replication
Consider the following components of the electron transport chain that function during cellular respiration. Which is most electronegative?
Complex IV
Which of the following illuminates the proper order of progression through the cell cycle?
G1 -> S -> G2 -> M
A cell that has completely replicated its DNA bot not yet undergone division is
G2
After telophase I of meiosis, what is the chromosomal makeup of each daughter cell?
Haploid, and the chromosomes are each composed of two chromatids
Which one of the following is a completely true statement?
Iodine stains starch and when together they absorb 560nm wavelength light
When does the cell cycle checkpoint that functions during mitosis
during metaphase
Which of the following is a defining characteristic of a dominant allele?
Its phenotype is expressed even in the presence of a recessive allele
Which of the following is not part of photosynthesis
Krebs cycle
In the electron transport system that functions during cellular respiration___________ is an electron donor and __________ is the final electron acceptor
NADH; O2
During fermentation in humans, electrons from _________ are used to reduce ________ producing lactic acid
NADH; pyruvate
The Calvin cycle uses ATP and NADPH to do what
Reduce CO2 to make sugars
A plant that produces round peas is crossed with a plant that produces wrinkled peas. The F1 generation is 1/2 round and 1/2 wrinkled. What are the genotypes of the parents?
Rr x rr
How do C4 plants that are not CAM plants separate their Calvin cycle reactions from their C4 cycle reactions?
The C4 and Calvin cycles are in different cells
If one of your bacterial colonies growing on an agar plate containing ampicillin, IPTG, and X-Gal was white in color, which one of the following conclusions can you most confidently make
The cells in the colony carried plasmids lacking a functional LacZ gene
Which of the following statements about a pair or homologous chromosomes is true?
They carry the same sets of genes but not necessarily the same alleles for every gene
If Lisa belongs to blood group type AB she could NOT possibly have the following set of parents
Type AB mother and Type O father
Consider that eye color in rabbits is sex linked and that all white eyes are the recessive mutant phenotype. Two parents of unknown genotype mate. 1/4 of ALL of their offspring and 1/2 of their MALE offspring are white eyed. What are the genotypes of the parents?
X^mX, XY
Absorption spectrophotometry revealed that spinach pigments
absorb different wavelenghts of light to different extents
Where would you expect to find proton gradients in plant cells?
across the inner mitochondrial membrane and across the thylakoid membrane
A man's X-linked allele would likely pass it onto
all of his daughters
During which phase of mitosis do the sister chromatids separate
anaphase
when are sister chromatids separated from each other during mitosis
anaphase
When would you expect the levels of the S phase cyclin to peak
at the transition of G1 to S or early in S
The role of the kinetochore in mitosis is to
attach microtubules to the chromatids and move chromatids along the microtubules as they shorten
"No two gametes are genetically identical" why?
because of crossing over and independent assortment of homologs
What is the leading theory for why sexual reproduction persists in so many species?
because it generates a population of genetically diverse individuals
in the cell cycle experiments by Howard and Pelc why did they use radioactive thymidine
because it would label newly-replicated DNA
Why would you expect the % transmittance of 560nm wavelength light to increase during the course of an experiment in which starch is being digested with amylase
because the concentration of iodine-stained starch decreases
Chlorophylls absorb light in the __________ range where as carotenoids absorb light in the ____________ range
blue and red; blue and green
Rubisco is involved in which two processes
carbon fixation and photorespiration
The main difference between C4 and CAM plants is that
carbon storage and the Calvin cycle occur in different cells in C4 plants, but in the same cells in CAM plants
Which of the following happens during interphase?
centrosome duplication
Which of the following series of events is in the proper order
centrosome duplication -> prophase -> metaphase -> anaphase -> telophase
The pigments you separated by paper chromatography differed from one another in ________ and in their __________ in the relatively ___________ chromatography solvent
color; solubility; nonpolar
Which of the following does not happen during meiosis II
crossing over
Which is not produced by the light-dependent reactions of photosynthesis
glucose
Which of the following conditions would you expect to increase the rate of conversion of pyruvate to acetyl CoA (pyruvate processing)
high NAD+concentrations
A gardener crosses a red daisy with a white daisy expecting all red daisies. Instead his cross yields all pink daisies. This is likely an example of
incomplete dominance
Assume that a species of flowering plant's flower color is controlled by a single gene with only two alleles in the population and that a cross between purple-flowered plants and white flowered plants produces lavender flowered offspring. This would be an example of
incomplete dominance
One reason for genetic diversity among daughter cells in meiosis is due to crossing over, and another is due to
independent assortment of homologous chromosomes
Cyclins
interact with cyclin-dependent kinases to initiate phases of the cell cycle
The CO2 used by photosynthesis
is fixed during the Calvin cycle
Synapsis typically occurs in prophase of
meiosis I
Typically, genetically identical daughter cells result from which type(s) of cell division
mitosis but not meiosis I or meiosis II
Light with a shorter wavelength has ________ energy compared to that of a longer wavelenght
more
Paper chromatography followed by extraction and spectrophotometry revealed that spinach contains
multiple pigments
Crossing over usually contributes to genetic variation by exchanging chromosomal segments between
non-sister chromatids of homologous chromosmes
In which two processes is ATP synthase involved
oxidative phosphorylation and photosystem II
During the citric acid (Krebs) cycle, acetyl Co-A is _____________ to form ______________
oxidized; carbon dioxide
In Mendel's experiments, he observed traits of garden pea plants. Observable traits are known as the ____________ of an organism such as a pea plant
phenotype
Cyclin-dependent kinases
phosphorylate proteins that regulate the cell cycle
The electrons going through Photosystem I are taken from
photosystem II
CAM plants
produce ATP, NADPH, and glucose during the day, but 4 carbon molecules at night
CAM plants
produce ATP, NADPH, and glucose during the day, but 4-carbon molecules at night
What is the proper order of progression through mitosis
prophase -> prometaphase -> metaphase -> anaphase -> telophase
Crossing over typically occurs in
prophase of meiosis I
Which of the following describes the flow of electrons through photosystem I?
reaction center chlorophyll -> ferrodoxin -> NADPH
Pseudohypertrophic muscular dystrophy is a human disorder that causes gradual deterioration of the muscles. Boys are affected far more often than girls and are usually born to phenotypically normal parents. Especially in the psat, due to the severity of the disease, boys often died in their teens. This disorder is likely to be caused by a ___________ allele
recessive, sex linked
The concentrations of cyclin-dependent kinases ________ while concentrations of cyclins ___________ during the cell cycle
remain the same; fluctuate
If your mutant strain of Drosophila melanogaster is homozygous for an autosomal mutation which of the following would you expect regardless of whether the mutation is dominant or recessive
results of your two reciprocal parent crosses should be similar
Which of the following is not a characteristic of meiosis
same number of chromosomes per cell before and after
Meiosis II is similar to mitosis in that
sister chromatids are separated in both
At anaphase of mitosis
sister chromatids separate and migrate to opposite ends of the cell
As a reaction catalyzed by amylase progresses, the amount of _________ in the reaction ___________ so later samples mixed with iodine will be ____________ in color than earlier samples mixed with iodine
starch; decrease; lighter
A key difference between mitosis and meiosis in most species is
synapsis of homologous chromosomes occurs only in meiosis
During which phase of mitosis do chromosomes decondense and become diffuse chromatin, while nuclear envelopes (nuclear membranes) form?
telophase
How could you distinguish a cell in metaphase of mitosis from one in metaphase in meiosis II
the cell in metaphase of meiosis II will have half as many chromosomes as the cell in metaphase of mitosis
Crossing over is
the exchange of segments between the chromatids of homologous chromosomes
Where does the citric acid (Krebs) cycle take place
the mitochondrial matrix
If you close a plant's stomata for a long time, and the plant is neither a C4 nor a CAM plant, which of the following will occur?
the plant will shift from photosynthesis to photorespiration
Where do the electrons that regenerate the reaction center chlorophyll in photosystem II come from
the splitting of water
What is the purpose of fermentation?
to oxidize NADH back to NAD+ so that glycolysis can continue
Mitosis results in
two genetically identical daughter cells, each with the same number of chromosomes as the parent cell
The electrons going through photosystem II are taken from
water
the oxygen produced by photosynthesis comes from
water split by photolysis
What is cyclic phosphorylation
when electrons from photosystem I are used to generate a proton gradient for ATP production
