UMN BIOL 1009 Midterm 2 Study Questions
What is the probability that a male will inherit an X-linked recessive allele from his father?
0%
The centimorgan (cM) is a unit named in honor of Thomas Hunt Morgan. To what is it equal?
1% frequency of recombination between two genes
If a heterozygous plant is allowed to self-pollinate, what proportion of the offspring will also be heterozygous?
1/2
Michelle and Keith are apparently normal, but their daughter was born with alkaptonuria, an inherited metabolic disorder. If alkaptonuria is like most other human hereditary disorders, the probability of their next child being born with alkaptonuria is _____.
1/4
If there are 20 chromatids in a cell, how many centromeres are there?
10
If each parent can produce 100 genetically distinct gametes, how many genetically distinct offspring can two parents produce?
10,000
Cinnabar eyes is a sex-linked recessive characteristic in fruit flies. If a female having cinnabar eyes is crossed with a wild-type male, what percentage of the F1 males will have cinnabar eyes?
100%
Substrate-level phosphorylation accounts for approximately what percentage of the ATP formed directly by the reactions of glycolysis?
100%
Two true-breeding stocks of pea plants are crossed. One parent has red, axial flowers and the other has white, terminal flowers; all F1 individuals have red, axial flowers. The genes for flower color and location assort independently. If 1,000 F2 offspring resulted from the cross, approximately how many of them would you expect to have red, terminal flowers?
190
In a particular plant, leaf color is controlled by gene locus D. Plants with at least one allele Dhave dark green leaves, and plants with the homozygous recessive dd genotype have light green leaves. A true-breeding dark-leaved plant is crossed with a light-leaved one, and the F1 offspring is allowed to self-pollinate. The predicted outcome of the F2 is diagrammed in the Punnett square shown in the figure below, where 1, 2, 3, and 4 represent the genotypes corresponding to each box within the square. Which of the boxes marked 1-4 correspond to plants with a heterozygous genotype?
2 and 3
The enzyme polynucleotide phosphorylase randomly assembles nucleotides into a polynucleotide polymer. You add polynucleotide phosphorylase to a solution of ATP, GTP, and UTP. How many artificial mRNA 3 nucleotide codons could possibly be made?
27
A part of an mRNA molecule with the following sequence is being read by a ribosome: 5' CCG-ACG 3' (mRNA). The anticodon loop of the first tRNA that will complement this mRNA is
3' GGC 5'
Two true-breeding stocks of pea plants are crossed. One parent has red, axial flowers and the other has white, terminal flowers; all F1 individuals have red, axial flowers. The genes for flower color and location assort independently. Among the F2 offspring, what is the probability of plants with white axial flowers?
3/16
What would be the sequence of the DNA molecule made by replication of the DNA molecule shown below?
5' TCCGGAA 3'
The nucleotide sequence of the coding strand of a DNA molecule is shown below. What will be the nucleotide sequence of the RNA molecule made from this segment of DNA? 5' TTTAAGG 3'
5' UUUAAGG 3'
Which of the following statements is TRUE?
5' and 3' untranslated regions (UTRs) are parts of exons, but do not code for proteins.
The nucleotide sequence of the template strand of a DNA molecule is shown below. What will be the nucleotide sequence of the RNA molecule made from this segment of DNA? 5' ATGCGTA 3'
5'UACGCAU 3'
Human blood groups are governed by three alleles, A, B, and O. A and B are codominant and O is recessive to both. If a woman with type O blood is expecting a child. Her husband is type A. Both the woman's father and her husband's father had type B blood. What is the probability that the child will have type O blood?
50%
In werewolves (hypothetically), pointy ears (P) are dominant over round ears (p). The gene is on the X chromosome. (Sex determination in werewolves is the same as for "other" humans.) A certain female werewolf has pointy ears even though her father had round ears. What percentage of her sons will have round ears if she mates with a werewolf with round ears?
50%
Radish flowers may be red, purple, or white. A cross between a red-flowered plant and a white-flowered plant yields all-purple offspring. The part of the radish we eat may be oval or long, with long being the dominant characteristic. If true-breeding red long radishes are crossed with true-breeding white oval radishes, which of the following phenotypic ratios would be expected in the F2 generation?
6:3:3:2:1:1
In humans, male-pattern baldness is controlled by an autosomal gene (= a gene that is found on a chromosome other than an X or Y chromosome) that occurs in two allelic forms. Allele Hndetermines nonbaldness, and allele Hb determines pattern baldness. In males, because of the presence of testosterone, allele Hb is dominant over Hn. If a man and woman both with genotype HnHb have a son, what is the chance that he will eventually be bald?
75%
During translation (polypeptide elongation), charged tRNAs enter the ribosome at the
A site
A particular triplet of bases in the coding strand of a gene is TTT. If an mRNA is made from this gene, the anticodon on the tRNA that will bind the codon on the mRNA is
AAA
Four genes (A, B, C, and D) are on the same chromosome. The recombination frequencies are as follows: A-B: 19%; B-C: 14%; A-C: 5%; B-D: 2%; A-D: 21%; C-D: 16%. Based on this information, which sequence of genes is correct?
ACBD
In a mitochondrion, if the matrix ATP concentration is high, and the intermembrane space proton concentration is too low to generate sufficient proton-motive force, then
ATP synthase will hydrolyze ATP and pump protons into the intermembrane space.
The nitrogenous base adenine is found in all members of which group?
ATP, RNA, and DNA
The oxygen consumed during cellular respiration is involved directly in which process or event?
Accepting electrons at the end of the electron transport chain
Transfer RNAs, or tRNAs
All of these answers are correct.
Which of these statements is FALSE?
At sexual maturity, ovaries and testes produce diploid gametes by meiosis.
Which of the following statements about repressor proteins is FALSE?
Binding of a corepressor stabilizes repressor proteins in their inactive shape
Which step in in the figure shown below is a redox reaction?
C
In the reaction shown below CH4 + 2 O2 → CO2 + energy + 2 H2O
CH4 is the reducing agent and O2 is the oxidizing agent
A spaceship is designed to support animal life for a multiyear voyage to the outer planets of the solar system. Plants will be grown to provide oxygen and to recycle carbon dioxide. If the power fails and the lights go dark, what will happen to CO2 levels?
CO2 will rise as a result of both animal and plant respiration.
Which of the following is a protein maintained at constant levels throughout the cell cycle that requires cyclin to become catalytically active?
Cdk
Which of the following statements is TRUE?
DNA is transcribed and RNA is translated
A biochemist isolates, purifies, and combines in a test tube a variety of molecules needed for DNA replication. When she adds some DNA to the mixture, replication occurs, but each DNA molecule consists of a normal strand paired with numerous segments of DNA a few hundred nucleotides long. What has she probably left out of the mixture?
DNA ligase
What is the basis for the difference in how the leading and lagging strands of DNA molecules are synthesized?
DNA polymerase can join new nucleotides only to the 3' end of a growing strand.
To view and analyze human chromosomes as a cell is dividing, which of the following is/are required?
DNA stain and a light microscope
Physically, what are different alleles?
Different alleles are different DNA sequences found at the same locus (location) on homologous chromosomes.
Sturtevant provided genetic evidence for the existence of four pairs of chromosomes in Drosophila in which of these ways?
Drosophila genes cluster into four distinct groups of linked genes.
E. coli cells grown on 15N medium are transferred to 14N medium and allowed to grow for two more generations (two rounds of DNA replication). DNA extracted from these cells is centrifuged. Which of the samples shown in the figure below shows the density distribution of DNA you would expect in this experiment?
E
The figures show a diploid nucleus with four chromosomes. There are two pairs of homologous chromosomes, one long and the other short. One haploid set is symbolized as black and the other haploid set is gray. The chromosomes in the unlettered circle have not yet replicated. What is the correct chromosomal condition for one daughter nucleus at telophase of mitosis?
E
Which of the following is true of a species that has a chromosome number of 2n = 16?
Each cell has eight homologous pairs.
A certain (hypothetical) organism is diploid, has either blue or orange wings as the consequence of one of its genes on chromosome 12, and has either long or short antennae as the result of a second gene on chromosome 19, as shown in the figure below. A female with a paternal set of one orange allele of the wing color gene and one long allele of the antennae length gene and a maternal set comprised of one blue allele of the wing color gene and one short allele of the antennae length gene is expected to produce which of the following types of eggs after meiosis?
Each egg has a one-fourth chance of having either blue long, blue short, orange long, or orange short combinations.
Queen Victoria was a carrier of a recessive sex-linked allele for hemophilia. Which of the following possibilities could explain the presence of the hemophilia allele in her genotype?
Either her mother was a carrier or her father had hemophilia.
When electrons move closer to a more electronegative atom, what happens?
Energy is released and the more electronegative atom is reduced
Which of the following statements about RNA processing is FALSE?
Exons are cut out before mRNA leaves the nucleus.
Why are individuals with an extra chromosome 21, which causes Down syndrome, more numerous than individuals with an extra chromosome 3 or chromosome 16?
Extra copies of the other chromosomes are probably fatal to the developing embryo.
A particular cell has half as much DNA as some other cells in a mitotically active tissue. The cell in question is most likely in
G1
Measurements of the amount of DNA per nucleus were taken on a large number of cells from a growing fungus. The measured DNA levels ranged from 3 to 6 picograms per nucleus. In which stage of the cell cycle did the nucleus contain 6 picograms of DNA?
G2
A sexually reproducing animal has two unlinked genes, one for head shape (H) and one for tail length (T). Its genotype is HhTt. Which of the following genotypes is possible in a gamete from this organism?
HT
If a mother is heterozygous for a recessive sex-linked trait and her husband has the dominant allele, which one of the following is true about the probabilities for their children?
Half of their sons will have the recessive trait.
A woman is red-green color-blind. What can we conclude, if anything, about her father?
He is red-green color-blind.
A man who can roll his tongue and a woman who cannot roll her tongue have a son who can roll his tongue (R = can roll tongue; r = can't roll tongue). The son is curious about whether his father is homozygous or heterozygous for the tongue-rolling trait. Which of the following facts would allow him to know?
His father's mother cannot roll her tongue.
Which of the following happens at the conclusion of meiosis I?
Homologous chromosomes are separated.
In the figure, which number represents the point in the cell cycle during which the chromosomes are replicated?
II
Pairs of homolgous chromosomes are aligned at the equator of the spindle; alignment determines independent assortment during which of the following stages of meiosis: I. Prophase I V. Prophase II II. Metaphase I VI. Metaphase II III. Anaphase I VII. Anaphase II IV. Telophase I VIII. Telophase II
II
In the figure, the latter part of mitosis is represented by which numbered part(s) of the cycle?
IV
What happens to the short RNA "primers" that primase synthesizes and that are extended by DNA polymerase III during DNA replication?
In E. coli, DNA polymerase I removes the RNA primers and fills in the resulting gaps with deoxyribonucleotides
Which of the following is a true statement about sexual vs. asexual reproduction?
In sexual reproduction, individuals transmit 50% of their genes to each of their offspring.
Which of the following statements describes the eukaryotic chromosome?
It consists of a single linear molecule of double-stranded DNA plus proteins.
What is the role of DNA ligase during DNA replication?
It joins DNA fragments together.
A given organism has 46 chromosomes in its somatic cells. We can therefore conclude which of the following?
Its gametes must have 23 chromosomes.
Which of the following statements about the genetic code is TRUE?
Mitochondrial genes use a slightly different genetic code than nuclear genes.
What is meant by the statement that "the genetic code is redundant"?
Most amino acids are specified by more than one codon.
Human blood groups are governed by three alleles, A, B, and O. A and B are codominant and O is recessive to both. Which of the following matings cannot produce a child with blood type O? The letters refer to blood types (phenotypes).
O x AB
Why are there concerns about using increased telomerase activity to slow down the aging process?
One concern is that increasing telomerase activity could increase cancer rates.
Why did the F1 offspring of Mendel's classic pea cross always look like one of the two parental varieties?
One phenotype was completely dominant over another.
The absorption spectrum for chlorophyll a and the action spectrum for photosynthesis are not identical to each other. Why are they not identical?
Other pigments absorb light in addition to chlorophyll a.
_____ is usually less severe than _____, and _____ species have been observed in plants, fish, amphibians, and even mammals.
Polyploidy ... aneuploidy ... polyploid
Which of the following statements best describes the termination of transcription in prokaryotes?
RNA polymerase transcribes through the terminator sequence, causing the polymerase to separate from the DNA and release the transcript.
Successful passage through the M phase checkpoint allows for what to occur?
Separase enzyme cleaves cohesins and allows chromatids to separate.
X-linked genes differ from Y-linked genes in which of the following ways?
Sons and daughters have equal probabilities in inheriting a recessive allele of an X-linked gene from their mother, but only sons can inherit rare Y-linked genetic disorders from their father.
Which of the following relationships is correct?
Spindle fibers attach to the kinetochore; the kinetochore attaches to the centromere.
Which of the following best describes how chromosomes move toward the poles of the spindle during mitosis?
The chromosomes are "reeled in" by the contraction of spindle microtubules, and motor proteins of the kinetochores move the chromosomes along the spindle microtubules.
Which of the following statements is true of linkage?
The closer two genes are on a chromosome, the lower the probability that a crossover will occur between them.
Mendel accounted for the observation that traits which had disappeared in the F1 generation reappeared in the F2 generation by proposing that
The correct answer is: traits can be dominant or recessive, and the recessive traits were obscured by the dominant ones in the F1.
Which statement describes the functioning of photosystem II?
The electron vacancies in P680+ are filled by electrons derived from water.
In comparing DNA replication with transcription, which of the following is true only of DNA replication?
The entire template molecule is represented in the product.
Map units on a linkage map cannot be relied upon to calculate physical distances on a chromosome for which of the following reasons?
The frequency of crossing over varies along the length of the chromosome.
Cystic fibrosis, which is usually lethal before the age of reproduction, is a homozygous recessive trait. Why do cases continue to arise, even though people with the disease rarely live to reproduce?
The harmful allele "hides" within heterozygous individuals, and one-fourth of the offspring of two heterozygotes would be afflicted.
The difference between ATP and the nucleoside triphosphates used during DNA synthesis is that
The nucleoside triphosphates have the sugar deoxyribose; ATP has the sugar ribose.
Pea plants are tall if they have the genotype TT or Tt, and they are short if they have genotype tt. A tall plant is mated with a short plant. Which outcome below would indicate that the tall parent plant was heterozygous?
The ratio of tall offspring to short offspring is 1:1.
Chromatids are separated from each other.
The statement is true for mitosis and meiosis II.
In an experiment, DNA is allowed to replicate in an environment with all necessary enzymes, dATP, dCTP, dGTP, and radioactively labeled dTTP (3H thymidine) for several minutes and then switched to nonradioactive medium. It is then viewed by electron microscopy and autoradiography. The figure shown below represents the results. The grains in the figure represent radioactive material within the replicating eye. Which of the following is the most likely interpretation?
There are two replication forks going in opposite directions.
What is the reason that linked genes are inherited together?
They are located close together on the same chromosome.
Which of the following statements is true about protein synthesis in prokaryotes?
Translation can begin while transcription is still in progress.
Which of the following statements about translation is TRUE?
Translation of an mRNA begins at an AUG codon mRNA molecules are read by the translation machinery in the 5' to 3' direction. The 5' and 3' UTRs of an mRNA molecule are not translated.
The drawings below show a single pair of homologous chromosomes as they might appear during various stages of either mitosis or meiosis. Which diagram(s) represent anaphase II of meiosis?
V only
Centromeres of sister chromatids disjoin and chromatids separate during which of the following stages of meiosis: I. Prophase I V. Prophase II II. Metaphase I VI. Metaphase II III. Anaphase I VII. Anaphase II IV. Telophase I VIII. Telophase II
VII
A genetic defect in humans results in the absence of sweat glands in the skin. Some men have this defect all over their bodies, but in women it is usually expressed in a peculiar way: A woman with this defect typically has small patches of skin with sweat glands and other patches without sweat glands. In women, the pattern of sweat-gland distribution can best be explained by _____.
X chromosome inactivation
Red-green color blindness is a sex-linked recessive trait in humans. Two people with normal color vision have a color-blind son. What are the genotypes of the parents?
XCXc and XCY
Which of the following intermediary metabolites enters the citric acid cycle and is formed, in part, by the removal of a carbon (CO2) from one molecule of pyruvate?
acetyl CoA
The movement of protons that occurs during transfer of electrons through the electron transport chain is an example of
active transport
Drosophila (fruit flies) usually have long wings, but mutations in the BT gene can result in bent wings and mutations in the VG gene can result in vestigial wings. If a homozygous bent wing fly is mated with a homozygous vestigial wing fly, which of the following offspring would you expect? Note that flies that have one wild-type allele and one mutant allele of the BTgene are represented by +bt, and flies that have one wild-type allele and one mutant allele of the VG gene are represented by +vg.
all +bt +vg heterozygotes
Which of the following statements about pre-mRNAs (primary mRNAs) is correct?
all of these answers are correct
Translation of mRNA
almost always begins at an AUG codon, which specifies methionine
When the ribosome reaches a stop codon on the mRNA, no corresponding tRNA enters the A site. If the translation reaction were to be experimentally stopped at this point, which of the following would you be able to isolate?
an assembled ribosome with a polypeptide attached to the tRNA in the P site
A "Barr body" is
an inactive X chromosome
Cells that have a number of chromosomes different from the normal number for their species are known as _____.
aneuploid
When a person has Down syndrome, he or she has an extra chromosome 21. Therefore, Down syndrome is a kind of _____ and results from _____.
aneuploidy ... nondisjunction of chromosome 21 during meiosis I
Mitotic spindles
are formed from centrosomes
Cells in G0
are typically less likely to go into S phase than cells in G1 are
In a series of mapping experiments, the recombination frequencies for four different linked genes of Drosophila were determined as shown in the figure below. What is the order of these genes on a chromosome map?
b-rb-cn-vg
The formation of hydrogen bonds between complementary nucleotides is known as
base pairing
During translation, the role of release factors is to
bind the mRNA stop codon in the A site of the ribosome, causing release of the completed polypeptide
In photosynthetic cells, synthesis of ATP by the chemiosmotic mechanism occurs during
both photosynthesis and respiration.
Which of the following processes do NOT occur during S phase?
breakdown of the nuclear envelope
Redox reactions
can result in a transfer of electrons can result in a change in electron sharing in covalent bonds
Experiments with cohesins have found that
cohesins are protected from cleavage at the centromere during meiosis I.
The pairs of nucleotides that interact to join together two DNA strands are known as
complementary nucleotides
The "polyA" tail that is added to the 3' end of eukaryotic mRNA molecules
consists of a string of adenosine ribonucleotides
Which of the following is a protein synthesized at specific times during the cell cycle that associates with a kinase to form a catalytically active complex?
cyclin
Regulation of the cell cycle occurs at specific checkpoints that are controlled by synthesis and degradation of proteins called
cyclins
Certain molecules (polypeptides, mRNAs and other molecules) become unevenly distributed in egg cells and, consequently, in the two daughter cells formed by division of an egg cell. Some of these molecules then lead to expression of different sets of transcriptional activators in the daughter cells. These molecules are known as
cytoplasmic determinants
The elongation of the leading strand during DNA synthesis
depends on the action of DNA polymerase.
Genotype
describes the genes (or alleles of genes) carried by a particular individual.
The human genome is minimally contained in which of the following?
every human cell
During which part of the mitotic cell cycle are two-chromatid chromosomes found?
from G2 of interphase through metaphase
The table shows data obtained from a study of the length of time spent in each phase of the cell cycle by cells of three eukaryotic organisms designated beta, delta, and gamma. Of the following, the best conclusion concerning the difference between the S phases for beta and gamma is that
gamma contains more DNA than beta
A "sex-linked" gene is a
gene found on either the X or Y chromosomes
The recombination frequency between two gene loci is _____.
greater as the distance between the two loci increases
After telophase I of meiosis, the chromosomal makeup of each daughter cell is
haploid, and the chromosomes are each composed of two chromatids.
In a double-stranded DNA molecule, the two DNA strands base pair in such a way that the 5' end of one DNA strand base pairs with the 3' end of the other DNA strand. The two DNA strands are said to be
in an antiparallel arrangement
If the phenotype of a heterozygote is intermediate between the phenotypes of individuals homozygous for either allele, the alleles carried by that heterozygote must be what type of alleles?
incompletely dominant alleles
Phosphofructokinase is an allosteric enzyme that catalyzes the conversion of fructose 6-phosphate to fructose 1,6-bisphosphate, an early step of glycolysis. In the presence of oxygen, an increase in the amount of ATP in a cell would be expected to
inhibit the enzyme and thus slow the rates of glycolysis and the citric acid cycle.
The direct product of the reaction catalyzed by ribulose bisphosphate carboxylase oxygenase, or "Rubisco"
is not a sugar molecule and must be reduced using electrons from NADPH to form sugar molecules
An enzyme, ribulose bisphosphate carboxylase oxygenase, or "Rubisco", attaches CO2 to a 5-carbon long sugar to form a 6-carbon long molecule, which
is unstable and splits to form two 3-carbon long molecules
Spindle microtubules bind sister chromatids at
kinetochores
The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction
loses electrons and loses energy
Males are more often affected by sex-linked traits than females because
males only have one copy of the X chromosome.
A particular small interfering RNA (siRNA)
may help block translation of specific mRNAs
Homologous chromosomes move toward opposite poles of a dividing cell during
meiosis I.
Women (and all female mammals) have one active X chromosome per cell instead of two. What causes this?
modification of the XIST gene so that it is active only on one X chromosome, which then becomes inactive
Which of the following is NOT one of the three major cell cycle checkpoints we discussed?
nuclear envelope has fragmented
Which of the following represents the order of increasingly higher levels of organization of chromatin?
nucleosome, 30-nm chromatin fiber, looped domain
A certain (hypothetical) organism is diploid, has either blue or orange wings as the consequence of one of its genes on chromosome 12, and has either long or short antennae as the result of a second gene on chromosome 19, as shown in the figure below. If a certain female of this species has one chromosome 12 with a blue allele of the wing color gene and another chromosome 12 with an orange allele of the wing color gene, and has both number 19 chromosomes with short alleles of the antennae length gene, she will produce which of the following egg types?
one-half blue short and one-half orange short gene eggs
A linkage map _____.
orders genes on a chromosome based on recombination frequencies
The observable physical and physiological traits of an organism, which are determined by its genetic makeup, are its
phenotype
The covalent linkages joining together nucleotides in a DNA molecule are known as
phosphodiester linkages
Which of the following is NOT a typical modification of a eukaryotic primary (or precursor) mRNA?
phosphorylation
Ribosomes are composed of
polypeptides and RNAs
Movement of the chromosomes during anaphase would be most affected by a drug that
prevents shortening of microtubules.
When we see chiasmata under a microscope, that lets us know which of the following has occurred?
prophase I
Radish flowers may be red, purple, or white. A cross between a red-flowered plant and a white-flowered plant yields all-purple offspring. The part of the radish we eat may be oval or long, with long being the dominant characteristic. If true-breeding red long radishes are crossed with true-breeding white oval radishes, the F1 will be expected to be which of the following?
purple and long
What is the oxidizing agent in the following reaction? Pyruvate + NADH + H+ → Lactate + NAD+
pyruvate
Which of the following are directly associated with photosystem I?
receiving electrons from the thylakoid membrane electron transport chain
It is far more common to find human genetic disease caused by _____ alleles than by _____ alleles because _____.
recessive ... dominant ... harmful recessive alleles can survive in the heterozygote without any selection pressure against them
Which process is most directly driven by light energy?
removal of electrons from chlorophyll molecules
The energy from an excited electron can be passed from one pigment molecule to another via a process known as
resonance energy transfer
Transcription in eukaryotes requires which of the following in addition to RNA polymerase?
several transcription factors (TFs)
Meiosis II is similar to mitosis in that
sister chromatids separate during anaphase.
The ATP made during fermentation is generated by which of the following?
substrate-level phosphorylation
Which of the following occurs in meiosis but not in mitosis?
synapsis of chromosomes
Two plants are crossed, resulting in offspring with a 3:1 ratio for a particular trait. What does this suggest?
that the parents were both heterozygous for a single trait
Which pathways generate reduced electron carriers?
the citric acid cycle and glycolysis
"X inactivation" refers to
the inactivation of most of the genes on one X chromosome in genetic females
In mitochondria, during chemiosmosis protons move from the intermembrane space to the matrix, whereas in chloroplasts, during chemiosmosis protons move from
the inter-thylakoid space to the stroma.
The reactions that produce NADPH occur in
the light reactions alone.
Wild type refers to _____.
the most common phenotype thought to be found in the natural population
How do the nucleotides used to make RNA molecules differ from those used to make DNA molecules?
the nucleotides used to make RNA molecules have ribose instead of deoxyribose as their sugar and uracil instead of thymine as one of their nitrogenous bases
During translation, after the ribosome breaks the bond between the growing polypeptide chain and the tRNA in the P site and then forms a covalent (peptide) bond between the growing polypeptide chain and the amino acid attached to the tRNA in the A site,
the position of the ribosome on the mRNA shifts and a new, charged tRNA enters the A site of the ribosome
Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the stroma. This damage will have the most direct effect on which of the following processes?
the synthesis of ATP
During translation, after the ribosome breaks the bond between the growing polypeptide chain and the tRNA in the P site and then forms a covalent (peptide) bond between the growing polypeptide chain and the amino acid attached to the tRNA in the A site,
the tRNA that was in the P site is now in the E site and leaves the ribosome
Where are the molecules of the electron transport chain found in plant cells?
thylakoid membranes of chloroplasts and inner membranes of mitochondria
What is the function of DNA polymerase III?
to add nucleotides to the 3' end of a growing DNA strand
Why do chromosomes coil during mitosis?
to allow the chromosomes to move without becoming entangled and breaking
For the DNA molecule shown below, where would the promoter be located?
to the right of the template strand
Which of the following help form a transcription complex at a promoter?
transcription factors and RNA polymerase
Exposing inner mitochondrial membranes to ultrasonic vibrations will disrupt the membranes. However, the fragments will reseal "inside out." These little vesicles that result can still transfer electrons from NADH to oxygen and synthesize ATP. These inside-out membrane vesicles
will become acidic inside the vesicles when NADH is added.
The pedigree below is for a family, some of whose members exhibit the dominant trait, W. Affected individuals are indicated by a dark square or circle. What is the genotype of individual II-5?
ww