biology final exam PART 1
a maternal homologue and a paternal homologue synapse to form: - sister chromatids - a paternal pair - a tetrad - a maternal pair - a paternal pair
a tetrad
in asexual reproduction, new combinations of genes arise by - crossing over - random assortment of genes - mutation - random segregation of chromosomes into gametes - all of these
mutation
which process is absolutely necessary fro sexual reproduction to occur in a life cycle, but is not necessarily required for organisms that only reproduce asexually? - karyokinesis - meiosis - prokaryotic fission - cytokinesis - mitosis
meiosis
in comparing mitosis and meiosis, which of the following statements is true? - chromatids are present only in mitosis - both processes result in four cells - meiosis II resembles mitosis - meiosis i is more like mitosis that is meiosis II - synapis (pairing of chromosomes) occurs in both
meiosis II resembles mitosis
the main evolutionary advantage of sexual over asexual reproduction is that is produces _________ - all of the above - more variation among offspring - healthier offspring - more offspring per individual - clones of the parent
more variation among offspring
what are the possible phenotypes of the children if the mother has type A blood and the father has type AB blood? - all AB - A, B - A, B, or AB - A, B, O
A, B, or AB
which of the following are produced by meiosis? - all of the above - polar bodies - animal sperm - plant sperm - animal eggs
all of the above
during which of the following stages of meiosis do the sister centromeres separate? - metaphase II - anaphase I - metaphase I - anaphase II - telophase II
anaphase II
sister chromatids are joined at the centromere in all of the stages of meiosis listed below except: - anaphase II - metaphase I - telophase I - prophase II - metaphase II
anaphase II
the sister chromatids become separated during ___________ of meiosis - telophase I - metaphase I - anaphase II - prophase II - anaphase I
anaphase II
a pear plant with the genotype Aa can produce gametes containing: - either A or Aa - only the dominant A - only the reserve a - either A or a - either AA, Aa, and aa
either A or a
which process does not match the products? - electron transport and chemiosmosis - ATP, H2O - citric acid cycle - CO2, NADH, FADH2, ATP - formation of acetyl CoA - Acetyl CoA, CO2 - glycolysis - pyruvic acid, ATP, NADH - all of the processes match the products
electron transport and chemiosmosis - ATP, H2O
two martians fall in love and marry. one martian is homozygous for red eyes and the other is heterozygous. the recessive eye color is purple. what is the probability that they will have a child with purple eyes? - 100% - 50% - 25% - 75% - 0%
0%
during the citric acid cycle, each acetyl group entering the cycle yields: - 1 ATP, 4 NADH, and 2 CO2 - 1 ATP, 2 NADH, and 2 CO2 - 3 ATP, 2 NADH, and 1 CO2 - 4 ATP, 2 NADH, and 1 CO2 - 1 ATP, 2 NADH, and 4 CO2
1 ATP, 2 NADH, and 2 CO2
what are the predicted phenotypes of the male children from the union of a woman who is heterozygous for hemophilia and a man who has normal blood clotting characteristics? - all normal - 3 normal : 1 hemophilia - 1 hemophilia : 1 normal - 1 hemophilia : 3 normal - all hemophilias
1 hemophilia : 1 normal
what are the predicted phenotypes of the female children from the union of a woman who is heterozygous for hemophilia and a man who has normal blood clotting characteristics? (use punett square) - all carriers - 3 normal : 1 carrier - 1 normal : 1 carrier - 1 hemophilia : 2 normal : 1 carrier - all hemophiliacs
1 normal : 1 carrier
two martians fall in love and marry. one martian is homozygous for red eyes and the other is heterozygous. the recessive eye color is purple. what is the possibility that the alien couple will have a child that is heterozygous for eye color? - 1 - 1/2 - 1/4 - 3/4 - 0
1/2
a brilliant zoologist examines an intestine cell from a crayfish and counted 200 single chromosomes. what was the chromosome count of the eggs the crayfish was carrying? - 100 paired chromosomes - 50 single chromosomes - none of the above - 100 single chromosomes - 200 paired chromosomes
100 single chromosomes
glycolysis yields a net energy profit of __________ ATP molecules per molecule of glucose - 0 - 1 - 2 - 4 - 6
2
in a human cell at prophase I, there are ______ tetrads - 32 - 92 - 64 - 46 - 23
23
what is the probability that 2 lizards that are heterozygous for stripes on their tails (Ss) will produce an offspring that is homozygous for no stripes(ss)? - 100% - 50% - 25% - 12.5% - 0%
25%
the height of pea plants from a cross between parent plants heterozygous for height, in which tall is dominant would be: - all short - all tall - 1 tall : 2 short - 2 short : 2 tall - 3 tall : 1 short
3 tall : 1 short
an completely dominant gene controls the color of chickens so that BB produces black, Bb produces a slate-gray color called blue, and bb produces splashed white. a second gene controls comb shape, with the dominant gene R producing a rose comb and r producing a single comb. if a pure-breeding black chicken with a rose comb is mated to a splashed white chicken with a single comb in the F2 generation, what fraction of the offspring will be blue with rose comb? - 9/16 - 3/8 - 3/16 - 1/8 - 1/16
3/8
dogs have a diploid chromosome number of 78. how many chromosomes do their gametes have? - 39 - 156 - 78 - 234 - none of the above
39
in the Kreb's acid cycle, two acetyl CoA molecules are metabolized to: - 2 CO2 + 2 ATPs + 2 NADPH + 2 FADH - 4 CO2 + 6 NADH + 2 FADH2 + 2 ATP - fructose-1, 6-bisphosphate - glucose + 2 CO2 + 2 NADH + 2 FADH2 + 2 ATPs - 2 G3P`
4 CO2 + 6 NADH + 2 FADH2 + 2 ATP
a lizard with a striped tail is crossed with one having a spotted head, producing normal looking ( no stripes or spots) lizard progeny. what progeny would be expected to be produced by mating these progeny with each other, if the genes conferring stripes and spots were on different chromosomes? - equal numbers of normal, striped, spotted, and striped and spotted - 3 striped : 1 spotted - 9 striped and spotted : 3 spotted : 3 striped : 1 normal - 9 striped : 3 spotted : 1 striped or spotted - 9 normal : 3 striped : 3 spotted : 1 striped and spotted
9 normal : 3 striped : 3 spotted : 1 striped and spotted
what are the possible phenotypes of the children if the mother genotype is heterozygous A for blood type and the father is heterozygous B? - all AB - A, B - A, AB - A, B, O - A, B, AB, O
A, B, AB, O
in glycolysis, glucose receives two phosphate groups from ______________, thus forming fructose-1, 6-bisphosphate - ADP - ATP - a bisphosphate group - fructose-1, 6-bisphosphate - PGAL
ATP
which of the following represents the possible genotype(s) resulting from a cross between an individual homozygous (BB) and one heterozygous (Bb) individual? - BB and Bb - BB, Bb, and bb - BB only - Bb only - bb only
BB and Bb
which of the following represents the possible genotypes resulting from a cross between two individuals that are heterozygous (Bb)? - BB and Bb - BB, Bb, and bb - BB only - Bb only - bb only
BB, Bb, and bb
a type of degenerative disease of the nervous system caused by a lethal dominant allele is - Huntington's disease - Tay Sachs disease - Cystic fibrosis - achondroplasia - none of the above
Huntington's disease
in glycolysis, fructose-1, 6-bisphosphate splits, forming two molecules of: - ADP - citric acid - PGAL - glucose - acetyl CoA
PGAL
what are the possible genotypes of a female child from the union of a woman who is heterozygous for hemophilia and a man who has normal blood clotting characteristics? - X^HX^H or X^HX - XX or X^HX - X^HY^H - Hh - none of the above
XX or X^HX
the physical location of a particular gene on a chromosome is called: - an allele - a locus - a trait - a chromatid - none of the above
a locus
aerobic respiration is classified as: - a synthesis reaction - a hydrolysis reaction - a redox process - a polymerization reaction - an anabolic process
a redox process
mating an individual expressing a dominant phenotype, but whose genotype is unknown, with an individual expressing the corresponding recessive phenotype is an example of: - a heterozygous cross - an F1 cross - an F2 cross - a parental cross - a test cross
a test cross
which process is a transition from glycolysis to the Kreb Cycle? - conversion of PGAl to pyruvic acid - acetyl CoA formation - regeneration of reduced NAD+ - oxidative phosphorylation - substrate level phosphorylation
acetyl CoA formation
catabolic reactions: - are generally exergonic - usually produces ATP - are part of metabolism - may produce monosaccharides from polysaccharides - all of the above
all of the above
decarboxylations: - occur as part of the citric acid cycle - produce CO2 that is then exhaled via breathing - involve the removal of a carbon dioxide from a substance - are one type of general reaction that occurs during aerobic respiration - all of the above
all of the above
which of the following molecules can be used as a substrate for cellular respiration? - glucose - fats - proteins - polysaccharides - all of the above
all of the above
why is color-blindness more common in males than in females? - because females would have to receive two copies of the recessive color blindness gene to actually express the trait - because a male only needs to receive the recessive gene from his mother to be color-blind - because color-blindness is an X-linked trait - all of the above - none of the above
all of the above
__________ are alternative forms of a gene that govern the same feature, such as eye color, and occupy corresponding positions on homologous chromosomes - alleles - loci - homozygous - coupled traits - none of the above
alleles
mendel's principle of segregation states that: - alleles from one parent mask the expression of alleles from the other parent - alleles separate from each other before forming gametes - hybrids will express a phenotype intermediate between the two parental phenotypes - true-breeding parents produce offspring of the same phenotype - different loci separate from each other
alleles separate from each other before forming gametes
the type of genetic testing in which a sample of the fluid surrounding the baby is analyzed for a genetic disorder is called - chorionic villi sampling - amniocentesis - ultrasound - fetoscopy - none of the above
amniocentesis
`if a pure-breeding, long-tail cat (LL) is crossed with a pure-breeding cat with no tail (rumpy, ll) and a cat with a short tail (stumpy) is produced, the simplest explanation is - a mutation - an X linked gene - an incompletely dominant gene - a lethal gene - chromosomal aberration
an incompletely dominant gene
homologous chromosomes separate during : - metaphase I - anaphase II - anaphase I - metaphase II - telophase I
anaphase I
in humans assume that brown eyes are dominant and blue eyes are recessive. if two brown eyed individuals have a child with blue eyes that means: - both parents are heterozygous for brown eyes - both parents are heterozygous for eye color - there is a 1/4 chance that their second child will have brown eyes - there is a 50/50 chance that their second child will have blue eyes - none of the above
both parents are heterozygous for eye color
if a child has an AB type, the parents - must both have different blood types - must be A and B. but not AB - must be be AB - can be any blood type - can have different blood types, but neither can be blood type O
can have different blood types, but neither can be blood type O
in an experiment, mice were fed glucose containing a small amount of radioactive oxygen. the mice were closely monitored, and a few minutes later radiocative oxygen atoms showed up in - carbon dioxide - NADHH - ATP - oxygen - none of the above
carbon dioxide
cell respiration is most accurately described as a ____________ process - anabolic - catabolic - digestive - endergonic - fermentative
catabolic
the splitting of molecules into smaller components is referred to as: - anabolism - metabolism - catabolism - redox - photosynthesis
catabolism
most of the ATP made during cellular respiration occurs during a process known as - substrate level phosphorylation - pyruvic acid ----> acetyl CoA - chemiosmosis - fermentation - glycolysis
chemiosmosis
crossing over mixes up __________ - zygotes - alleles - gametes - chromosomes
chromosomes
one product of the initial (first) reaction of the Krebs Cycle is: - ATP - NADH - citric acid - oxaloacetate - acetyl-CoA
citric acid
select the processes that are matched with the incorrect amount of ATP produces by that process per glucose molecule - glycolysis --- 2 ATP (net) - citric acid cycle --- 4 ATP - electron transport chain --- 32 ATP - alcohol fermentation --- 0 ATP - lactate fermentation --- 0 ATP
citric acid cycle --- 4 ATP
breeding a yellow dog with a brown dog produced puppies with both yellow and brown hairs intermixed. this is an example of: - variegation - codominance - incomplete dominance - epistasis - a polygenic trait
codominance
susan, a mother with type B blood has a child with type O blood. she claims that Craig who has type A blood is the father. he claims he cannot possibly be the father. further blood tests ordered by the judge reveal that Craig is AA. the judge rules that - susan is right and craig must pay child support - craig is right and doesn't have to pay child support - susan cannot be the real mother of the child; there must have been an error made at the hospital - it is impossible to reach a decision based on the limited data available - none of these
craig is right and doesn't have to pay child support
the sources of genetic variation during meiosis are: - crossing-over and the random assortment of maternal and paternal chromosomes - random pairing of tetrads - crossing-over and random pairing of tetrads - random pairing of tetrads and random assortment of maternal and paternal chromosomes - random pairing of tetrads and mutations
crossing-over and the random assortment of maternal and paternal chromosomes
in eukaryotes, glycolysis occurs in the: - mitochondrial innere membrane - lysosomes - Golgi complex - cytosol - mitochondrial matrix
cytosol
a gene that affects, prevents, or masks the expression of a gene at another locus is a ___________ - recessive - dominant - epistatic - codominant - plieotropic
epistatic
fermentation is essentially glycolysis plus an extra step in which pyruvic acid is reduced to form lactic acid or alcohol and carbon dioxide. this last step - removes poisonous oxygen from the last environment - extracts more energy from glucose - enables the cell to recycle NAD+ - inactivates pyruvic acid - extracts no ATP from pyruvic acid
extracts no ATP from pyruvic acid
select the anaerobic pathway: - oxidative respiration - citric acid cycle - electron transport chain - fermenation - none of these choices are anaerobic
fermentation
four of the five answers listed below concern cells with two chromosome sets. select the exception. - zygote - diploid - skin cells - somatic cells - gamete
gamete
mendel verified true-breeding pea plants for certain traits before undertaking his experiments. the term "true-breeding" refers to: - genetically pure lines - organisms that have a high rate of reproduction - organisms that will produce identical copies of themselves upon reproduction - organisms that are heterozygous for a given trait - organisms that are hemizygous for all possible traits
genetically pure lines
when blood glucose levels decrease (as between meals) what reserves will be used first? - glycogen - lipids - proteins - steroids - amino acids
glycogen
which of the following metabolic pathways is common to all cells? - photosynthesis - electron transport chain - citric acid cycle - glycolysis - none of the above
glycolysis
which process does not match the location in skeletal muscle? - glycolysis --- mitochondria - formation of acetyl coenzyme A --- cytosol - citric acid cyle --- mitochondria - all of the processes are matched to the correct location
glycolysis --- mitchondria
a chemist has discovered a drug that blocks the enzyme aldolase. he wants to use the drug to kill bacteria in people with infections. the reason he cannot do this is because - bacteria are anaerobes that don't need to undergo glycolysis - glycolysis produces so little ATP that the drug will have little effect - human cells also undergo glycolysis, so the drug might also poison them - glycolysis can occur without the actions of enzymes - actually, the drug will have little effort on the bacteria
human cells also undergo glycolysis, so the drug might also poison them
which of the following is not one of the stages of the cell respiration? - glycolysis - formation of acetyl CoA - hydrolysis - citric acid cycle - electron transport
hydrolysis
crossing over is one of the most important events in meiosis because - the number of chromosomes allotted to each daughter cell must be halved - it produces new arrays of alleles on chromosomes - homologous chromatids must be separated into different daughter cells - all of these
it produces new arrays of alleles on chromosomes
genes that tend to be inherited together are said to be: - associated - related - similar - linked - alleles
linked
glucose is converted into glycogen primarily in the - brain - blood - pancreas - spleen - liver
liver
the man that devised a diagram predicting a genetic cross was ___________ - rober punnet - rex punnet - rodriquez punnet - reed punnet - none of the above
none of the above
substrate level phosphorylation - requires the presence of oxygen - requires the presence of NADH - occurs during glycolysis - produces most of the ATP during aerobic respiration - is not part of cellular respiration
occurs during glycolysis
the term "dominant" means that - both alleles can be expressed in a hybrid - all members of the F2 generation of a hybrid cross exhibit the dominant phenotype - one allele can mask the expression of another in a hybrid - the dominant phenotype shows up 100% of the offspring in all generations - the dominant phenotype is more beneficial than the recessive phenotype
one allele can mask the expression of another in a hybrid
mating a true-breeding pink rose plant with a true-breeding rose plant will produce: - plants with pink, red, and white roses - only plants with pink roses - plants with red or white roses in a 3:1 ratio - plants with white or red roses in a 3:1 ratio - none of the above
only plants with pink roses
the regeneration molecule in the Krebs Cycle is - pyruvic acid - acetyl CoA - fructose bisphosphate - oxaloacetic acid - citric acid
oxaloacetric acid
in aerobic respiration, the electrons associated with the hydrogen atoms in glucose are transferred to: - carbon in a series of steps - oxygen in a series of steps - NADH in a series of steps - the mitochondrial membranes - hydrogen ions
oxygen in a series of steps
how would you rid your muscles of the painful lactic acid build-up after strenuous exercise? - participate in light exercise while breathing deeply - lay in a hot tub with the remote control - cry.... while eating ice cream - alternate heat and ice while eating tons of chocolate - do nothing, it will go away in a month or so
participate in light exercise while breathing deeply
the physical appearance of an organism for a given trait is termed; - genetics - dominance - synapsis - genotype - phenotype
phenotype
which of the following is not a location where meiosis occurs? - human ovary - plant ovary - human testes - dog ovary - plant root tip
plant root tip
a particular gene that controls seed coat color in peas also determines the susceptibility of these peas to a particular disease. this situation is referred to as: - variegation - additive dominance - codominance - pleiotropy - incomplete dominance
pleiotropy
the additive effect of two or more genes on a single phenotype character is called - epistasis - multifactoral - polygenic inheritance - pleiotropy - multiple alleles
polygenic inheritance
homologous chromosomes synapse or pair during: - anaphase II - anaphase I - prophase II - telophase II - prophase I
propase I
crossing over usually occurs in which of the following stages of meiosis? - metaphase I - prophase I - interphase - telophase II - anaphase II
prophase I
in glycolysis, a six-carbon glucose molecule is converted to two three-carbon molecules of: - pyruvic acid - acetate - coenzyme A - oxaloacetic acid - citric acid
pyruvic acid
during aerobic respiration, oxygen is : - formed - reduced - oxidized - catobolized - decarboxylated
reduced
NADH and FADH2 are the products of: - decarboxylation reactions - reduction reactions - glycolysis - formation of acetyl coenzyme A - chemiosmosis
reduction reactions
four of the five answers listed below are characteristics of meiosis. select the exception. - involves the divisions - reduces the number of chromosomes - occurs in the gonads - produces haploid cells - results in producing genetically identical cells
results in producing genetically identical cells
meiosis functions in ________ - none of the above - asexual reproduction of single-celled eukaryotes - growth and tissue repair in multicelled species - asexual reproduction of single celled eukaryotes and growth and tissue repair in multicelled species - sexual reproduction
sexual reproduction
which of the following reproductive strategies would allow the most rapid adaptation to a changing environment? - switching between sexual and asexual reproduction - asexual reproduction - simultaneous sexual and asexual reproduction - neither strategy is more adaptive that any other - sexual reproduction
sexual reproduction
which of the following steps in the Kreb's cycle directly produces a molecule of ATP? - citric acid ---> isocitrate - isocitrate ---> ketoglutamic acid - fumaric acid ---> malic acid - succinate ---> fumaric acid - malic acid ---> oxaloacetic acid
succinate ---> fumaric acid
in peas, Mendel found that tall plants and yellow peas are dominant. the phenotype for a pea plant with the genotype TTtt would be: - heterozygous - Ty - short with yellow peas - tall with green peas - tall with yellow peas
tall with green peas
in peas, Mendel found that tall plants and yellow peas are dominant. the phenotype for a pea plant with the genotype TtYy would be: - heterozygous - tall with yellow peas - short with yellow peas - tall with green peas - short with green peas
tall with yellow peas
lactic acid production in muscle cells is - temporary - due to oxygen deficiency - an NAD regenerator - temporary and due to oxygen deficiency - permanent and due to oxygen deficiency
temporary and due to oxygen deficiency
a glucose molecule that is metabolized via aerobic respiration has been completely broken down and released as CO2 by the end of: - fermentation - the electron transport chain - glycolysis - ATP synthesis in the mitochondria - the citric acid cycle
the citric acid cycle
the transfer of electrons from glucose to oxygen during aerobic respiration takes place in a stepwise fashion through a number of intermediates rather than by direct transfer. this is because: - it is chemically impossible to transfer electrons directly from glucose to oxygen - the chemical intermediates donate some of their electrons in order to increase the electron pool - the energy of the electrons can be used to make ADP - the energy of the electrons can be used to make ATP - none of the above
the energy of the electrons can be used to make ATP
the chemical reaction illustrated in the figure is: *insert picture* - the first step in the citric acid cycle - the energy producing step of glycolysis - fermentation - part of the electron transport chain - none of the above
the energy producing step of glycolysis
when molecules are broken up in respiration - the heat produced in used to drive biological reactions - the oxygen in the compounds that are broke apart is used . as an energy source - the energy released in respiration is channeled into molecules of ATP - ATP is converted into ADP - ADP is released as a waste product
the energy released in respiration is channeled into molecules of ATP
the sex of a human is determined by: - the number of chromosomes - the number of autosomes - the presence of only one X chromosome - the number of sex chromosomes - the presence of Y chromosome
the presence of Y chromosome
the role of the oxygen molecules required to aerobic respiration is: - to accept the low energy electrons at the end of the electron transport chain - to form ATP - to produce CO2 - to store high energy electrons to pass to complex 1 of the electron transport chain - to accept electrons directly from either NADH or FADH2
to accept the low energy electrons at the end of the electron transport chain
Ubiquinol or Coenzyme Q: - transfers electrons - oxidizes glucose - is the ultimate source of energy in the citric acid cycle - tranfers phosphate to ATP - reduces glucose
transfers electrons
considering only glycolysis and the conversion of pyruvic acid molecules to acetyl CoA molecules, how many NADH molecules will be produced form one glucose molecule? - one - two - three - four - five
two
oxidative decarboxylation of two pyruvic yields: - two glucose molecules - two ATP + four CO2 + tow NADH - two PGAL - two acetyl groups + two CO2 - one fructose-1, 6-bisphosphate
two acetyl groups + two CO2
if a child belonged to blood type O, he or she could not have been produced by which set of parents - type A mother and type B father - type A mother and type O father - type AB mother and type O father - type O mother and type O father
type AB mother and type O father
in another experiment mice were allowed to breath oxygen gas laced with radioactive oxygen. in this experiment the radioactive oxygen atoms quickly showed up in - carbon dioxide - NADH - water - glucose - ethanol
water
four of the five answers listed below are characteristics of polar bodies. select the exception. - are produced during meiosis - have no known biological function - dumping places for excess genetic material - will serve as gametes if something happens to the egg
will serve as gametes if something happens to the egg
the principle of independent assortment is not true for: - incomplete dominance - mutations - heterozygous - homozygous - x-linked genes
x-linked genes
four of the five answers listed below are haploid cells. select the exception. - egg - spore - gametophyte - sperm - zygote
zygote
an animal with a diploid number of 36 chromosomes will have ______ chromosomes in its gametes and ________ chromosomes in its somatic cells - 36 ; 72 - 36 ; 18 - 36 ; 36 - 18 ; 36 - 18 ; 18
18 ; 36
meiosis typically results in the production of - 4 diploid cells - 1 triploid cell - 2 diploid cells - 2 haploid cells - 4 haploid cells
4 haploid cells
if a parent cell has 16 chromosomes and undergoes meiosis, the resulting cells will have how many chromosomes? -64 - 8 - 32 - 4 - 16
8
a human bone marrow cell in prophase of mitosis contains 46 chromosomes. how many chromatids does it contain altogether? - 46 - 46 or 92 depending on when during prophase you look - 92 - 23 - 23 or 46 depending on when during prophase you look
92
identify the locations in exhibit 12.3 where sperm are produced - A and B - A and C - B and D - B and C
A and C
identify the locations in exhibit 12.3 where ova are produced - A and B - A and C - A and D - B and D
B and D
mature nerve cells, which don't undergo cell division are arrested in _______ of the cell cycle - cytokinesis - G1 phase - G2 phase - metaphase - S phase
G1 phase
when do chromosomes appear slightly? - G2, metaphase, anaphase - G1 - G2 - S - G1, anaphase, telophase
G1, anaphase, telophase
interphase is the part of the cell cycle when ______ - mitosis proceeds - a cell ceases to function - the spindle forms - a cell grows and duplicates its DNA
a cell grows and duplicates its DNA
to prevent disastrous consequences, the eukaryotic cell cycle is controlled by - helper viruses - environmental signals - a very detailed rigid genetic program - a series of cell cycle checkpoints - the mitochondria
a series of cell cycle checkpoints
a picture of a dividing pigeon cell taken through a microscope shows that the cell contains 7 chromosomes, each consisting of 2 chromatids. this picture has been taken during - metaphase of mitosis - all of the above - G2 of the cell cycle - S phase of the cell cycle - prophase of mitosis
all of the above
the functions of mitotic cell division in the life cycles of an organism may include - growth - replacement of older cells - all of the above - asexual reproduction - repair of injured tissues
all of the above
through meiosis - alternate forms of genes are shuffled - offspring are provided with new gene combinations - the diploid chromosome number is reduced to haploid - parental DNA is divided and distributed to forming gametes - all of these
all of these
crossing over - alters the composition of chromosomes and results in new combinations of alleles being channeled into the daughter cells - involves nucleoli - involves breakages and exchanges being made between sister chromatids - generally results in binary fission - all of the above
alters the composition of chromosomes and results in new combinations of alleles being channeled into the daughter cells
homologous chromosomes - have genes for the same characteristics (even though the alleles may not be the same) - pair up during meiosis - are the same size - are in pairs, one chromosome of each pair from the father and one from the mother - are all of these
are all of these
which does not produce variation? - genetic recombination of alleles - asexual reproduction - crossing over - random alignment of chromosomes during meiosis - sexual reproduction
asexual reproduction
mitosis and cytoplasmic division function in _______ - growth and tissue repair in multicelled species - asexual reproduction of single-celled eukaryotes and growth and tissue repair in multicelled species - asexual reproduction of single-celled eukaryotes - gamete formation in bacteria and archaeans
asexual reproduction of single-celled eukaryotes and growth and tissue repair in multicelled species
cells from advanced malignant tumors often have very abnormal chromosomes and an abnormal number of chromosomes. what might explain the association between malignant tumors and chromosomal abnormalities? - transformation introduces new chromosomes into cells - cell cycle checkpoints are not in place to stop cells with chromosomes abnormalities - all of the above are true - cancer cels are no longer density-dependent - cancer cells are no longer anchorage-dependent
cell cycle checkpoints are not in place to stop cells with chromosomes abnormalities
cytokinesis in plant cell mitosis occurs by the formation of a(n) - golgi complex - cell plate - cell wall - mitotic spindle - aster
cell plate
the essence of meiosis is that - cells are formed that receive two members of each pair of homologous chromosomes - cells are formed that receive one member of each pair of homologous chromosomes - cells are formed that receive two copies of each member of each pair of homologous chromosomes - cells are formed that receive one copy of each member of each pair of homologous chromosomes - none of these occur
cells are formed that receive one member of each pair of homologous chromosomes
which does NOT occur in prophase I of meiosis? - condensation of chromatin - cytokinesis - formation of groups of four chromatids - crossing over - homologue paring
cytokinesis
a zygote contains the ________ complement of chromosomes - diploid - tetraploid - polypoid - haploid - none of the above
diploid
which of the following is most probable at a metaphase I alignment? - all paternal chromosomes are on the same side - all maternal chromosomes are on the same side - each side has a mixture of maternal and paternal chromosomes - all maternal chromosomes are on one side, all paternal are on the other - all of these are equally probable
each side has a mixture of maternal and paternal chromosomes
which of the following events does not occur in prophase II? - condensation of chromatin into chromosomes - formation of a new cell membrane - formation of the spindle - none of the above - removal of the nuclear membrane
formation of a new cell membrane
which of the following events does not occur in prophase? - removal of the nuclear membrane - formation of the spindle - none of the above, since all the events occur in prophase - formation of a new cell membrane - condensation of chromatin into chromosomes
formation of a new cell membrane
in intervals of interphase, G stands for _____ - genome - growth - gap - gene
gap
meiosis _______ the parental chromosome number - mixes up - halves - maintains - doubles
halves
each of the cells formed during telophase I is - ready to be fertilized - tetraploid - diploid - haploid - in synapsis
haploid
a cell in G2: - is in cytokinesis - has twice the amount of DNA present in a telophase nucleus - lacks a visible nuclear membrane - has visibly distinct chromosomes - is in mitosis
has twice the amount of DNA present in a telophase nucleus
which of the following is one of the very important differences between mitosis and meiosis? - interphase occurs only in mitosis - chromosomes align midway between spindle poles only in meiosis - sister chromatids separate only in meiosis - DNA is replicated only in mitosis - homologous chromosomes pair up only in meiosis
homologous chromosomes pair up only in meiosis
asexually produced daughter cells are - different from each other - different from the mother cell - identical to each other - identical to each other and identical to the mother cell - identical to the mother cell
identical to each other and identical to the mother cell
cyclin dependent kinase is ______ - an enzyme that attaches phosphate groups to other proteins - all of the above - the enzyme that catalyzes the attachment of chromosomes to microtubules - inactive, or turned off in the presence of cyclin - present only during the S phase of the cell cycle
inactive, or turned off in the presence of cyclin
most cells spend the majority of their lives in ______ - metaphase - prophase - telophase - anaphase - interphase
interphase
only _____ is not a stage of mitosis - interphase - prophase - metaphase - anaphase - telophase
interphase
the chromosomal DNA is duplicated in _______ of meiosis - prophase II - prophase I - metaphase I - interphase - anaphase II
interphase
the image of the chromosomes of an individual organism is called a: - kinetochore - karyotype - centromere - centriole - chromosome plot
karyotype
the spindle attaches to the chromosomes at the ________ - centrosome - contractile ring - centromere - centriole - kinetochore of the centromere
kinetochore of the centromere
the kinetochore serves which of the following functions? - kinetochores anchor spindle fibers to the centrioles - kinetochores attach to microtubules during mitosis - kinetochores regulate the length of the cell cycle - kinetochores are the site of DNA synthesis - kinetochores are involved in cytokinesis
kinetochores attach to microtubules during mitosis
besides the ability of some cancer cells to overproliferate, what else could logically result in a tumor? - none of the above - inability of chromosomes to meet at the metaphase plate - lack of appropriate apoptosis - changes in the order of cell cycle stages - inability to form spindles
lack of appropriate apoptosis
the correct number of chromosomes is maintained during sexual reproduction by: - meiosis, which reduces the chromosome number by half - replication of chromosomes twice during meiosis - mitosis, which maintains the original chromosome number - a process by which one half of the chromosomes in gametes are removed - chromosome doubling in the newly formed zygote`
meiosis, which reduces the chromosome number by half
if a child more strongly resembles the maternal grandmother than the maternal grandfather, the explanation could be due to random chromosome alignment during the mother's - telophase I - metaphase II - prophase I - metaphase I - anaphase II
metaphase I
the chromosomes align at the midpoint of the spindle during _______ - metaphase - anaphase - interphase - telophase - cytokinesis - prophase
metaphse
a culture of mouse cells is treated with a chemical that interferes with the activity of microfilaments. which of the following will probably be affected the most? - pairing of chromosomes in S phase - cytokinesis - joining of the sister chromatids at the centromere - mitosis - chromosomes duplication
mitosis
the _____ is responsible for the separation of the chromosomes during _____ of mitosis - centromere ; telophase - mitotic spindle ; anaphase - kinetochore ; prophase - cell wall ; anaphase - flagellum ; metaphase
mitotic spindle ; anaphase
how many mature eggs are produced from a single initial cycle? - four - two - three - one - eight
one
the mature ovum is produced by maturation of the - oogonium - oocyte - secondary polar body - polar body I - none of these
oocyte
under favorable conditions, during which phase of meiosis with the chromosomes appear as packets for four chromatids? - prophase I - anaphase II - telophase II - metaphase II
prophase I
sexual reproduction: - produces genetic clones and requires less tissue differentiation than asexual reproduction - results in new combinations of genetic traits - leads to uniform characteristics in a population - produces genetic clones - requires less tissue differentiation than asexual reproduction
results in a new combination of genetic traits
which of the following events does not occur during meiosis I? - crossing over between homologous chromosomes - separation of homologous chromosomes - DNA exchange - separation of sister chromatids - pairing of homologous chromosomes
separation of sister chromatids
movement of the chromosomes during anaphase would be most affected by a drug that prevents - shortening of microtubules - elongation of microtubules - nuclear envelope breakdown - formation of a cleavage furrow
shortening of microtubules
copies of chromosomes linked together at their centromeres at the beginning of meiosis are appropriately called what kind of chromatids? - daughter - sister - homologous - mother - none of these
sister
during meiosis II - sister chromatids of each chromosome are separated from each other - homologous chromosomes separate - homologous chromosomes pair up - cytokinesis results in the formation of a total of two cells - sister chromatids exchange parts
sister chromatids of each chromosome are separated from each other
if meiosis did not occur in sexually reproducing organisms, - the zygote would be haploid - gametes would be haploid - the chromosome number would double in each generation - mitosis would be sufficient - eggs would be diploid but sperm would be haploid
the chromosome number would double in each generatio
a cell is in metaphase if: - the nuclear envelope is clearly visible - none of the above - the chromosomes are visible as thread-like structures - the chromosomes are aligned on the equatorial plane of the cell - the chromosomes are separated into distinct groups at opposite poles of the cell
the chromosomes are aligned on the equatorial plane of the cell
after mitosis, the chromosome number of a descendant cell is ____ the parent's cell - one half of - doubled compared to - the same as - rearranged compared to
the same as
a duplicated chromosome has ________ chromatids - three - one - four - two
two