BIO Final Exam
The following RNA strand was produced: 5′ AUG GCG UUU 3′ Which of the following DNA strands could have been the template for this RNA? 3' AUG GCG UUU 5' 3' UAC CGC AAA 5' 3' TAC CGC AAA 5' 3' CGT TAT GGG 5'
3' TAC CGC AAA 5'
proofreading of DNA is done in _____ direction
3' to 5'
During elongation, a tRNA binds to the ____ site
A
As elongation begins, start codon is located at P site, next codon is at
A Site
Missense Mutation
A base-pair substitution that results in a codon that codes for a different amino acid which changes amino acid sequence
base-pair substitution
A type of point mutation; the replacement of one nucleotide and its partner in the complementary DNA strand by another pair of nucleotides.
START codon
AUG
Metaphase-Anaphase Transition
- commitment made to segregate chromosomes - checks for chromosome attachment to spindle
Approximately how much of the human genome encodes proteins
2%
What can result in multiple different protein products
Alternative RNA splicing
benign tumor
An abnormal mass of cells that remains at its original site in the body.
recessive allele
An allele that is masked when a dominant allele is present
nondisjunction
An error in meiosis or mitosis in which members of a pair of homologous chromosomes or a pair of sister chromatids fail to separate properly from each other.
heterozygous
An organism that has two different alleles for a trait
homozygous
An organism that has two identical alleles for a trait
phenotype
An organism's physical appearance, or visible traits.
The excision repair pathway that correcs signle damanged bases is
Base excision repair (BER)
The Calvin cycle uses these molecules ___________ to make ___________. Carbon dioxide, ATP, and NADPH .......... glyceraldehyde-3-phosphate NADPH and ATP ............... carbon dioxide Light energy, carbon dioxide and glyceraldehyde-3-phosphate ..............oxygen NADH, FADH2 and carbon dioxide............ glyceraldehyde-3-phosphate
Carbon dioxide, ATP, and NADPH .......... glyceraldehyde-3-phosphate
what is included in Genome of Gene Expression
Differentiation, Chromatin Decondensation, DNA Methylation
Which does not describe gel electrophoresis
Dna fragments that are larger
During translocation, tRNA holding the polypeptide chain moves from A to P site and the empty tRNA moves to
E site
Which of the following is not a true statement regarding the genetic code? The genetic code is nonoverlapping. The genetic code is degenerate. Each codon represents a different amino acid. The genetic code is triplet-based.
Each codon represents a different amino acid.
Which of the following are components of Chargaff's rule of bases? %A = %T %G = %C Each of these are true. %C + %T = %A + %G
Each of these are true.
Oxidation is the removal of ____ which usually is accompanied by removal of protons in a process called ____ in biological systems. Electrons; hydrogenation Protons; hydrogenation Protons; dehydrogenation Electrons; dehydrogenation
Electrons; dehydrogenation
When lactose is present, transcription gene is turned ___
ON
RNA splicing
Process by which the introns are removed from RNA transcripts and the remaining exons are joined together.
crossing over
Process in which homologous chromosomes exchange portions of their chromatids during prophase 1 (pachytene)
How does eukaryotic gene regulation differ from that of prokaryotic gene regulation?
Prokaryotes undergo transcription/translation in the same location Eukaryotes occur in nucleus and cytosol
During what stage of meiosis does homologous recombination occur?
Prophase 1
when does homologous recombination occur
Prophase 1
DNA is different from RNA in that RNA is made up five bases, whereas DNA is made up of four. RNA contains an additional oxygen atom on the ribose sugar. In general, RNA molecules are longer than DNA molecules. Each of these statements are true.
RNA contains an additional oxygen atom on the ribose sugar.
Initiation
RNA polymerase initiates synthesis of RNA using DNA strand as a template
Elongation
RNA polymerase moves along template which unwinds and elongates RNA in 5' to 3' direction
Multistep process of cancer
Initiation, Promotion, Progression
The cell spends the majority of its life in
Interphase
How does the antidepressant drug Prozac® work? It blocks reuptake of specific neurotransmitters It acts as an antagonist It binds the neurotransmitter to assist in reuptake It degrades the neurotransmitter
It blocks reuptake of specific neurotransmitters
Which of these is not true about cytokinesis? It is cytoplasmic division It occurs during telophase A cleavage furrow forms in animal cells It is a stage of mitosis
It is a stage of mitosis
Which of the following explains what happens to oxygen produced by the light-dependent reactions? It is released into the atmosphere. It is recycled as a reactant in another light-dependent reaction. It combines with NADPH to produce water. It is used in the Calvin cycle.
It is released into the atmosphere.
Which of these is not a function of DNA polymerase
Joining DNA fragments together
Which of the following is true regarding the process of transcription? DNA polymerases control transcription. The three stages of transcription are initiation, elimination, and reduction. Transcription occurs for individual genes. Transcription uses both strands of DNA to make mRNA
Transcription occurs for individual genes.
T/F Not all tumor promotors are foreign substances
True
Stop codon
UAA, UAG, UGA
Radition DNA damage
UV Radiation X Rays and Related
How does cancer spread?
Metastasis and Invasion
p53
Molecule that prevents mitosis in cells with damaged DNA. Changes in its activity can result in cancer.
replicon
Unit of replication, consisting of DNA from the origin of replication to the point at which replication on either side of the origin ends.
In order to test the effectiveness of a new vaccine, 50 volunteers are selected and divided into two groups. One group will be the control group and the other will be the experimental group. Both groups are given a pill to take that is identical in size, shape, color and texture. Which of these describes the independent variable? a. The addition of the vaccine to the pills that were given to the volunteers b. The size, shape, color, and texture of the pills given to the volunteers. c. The health of the volunteers receiving the pill d.the pills given to the volunteers in both groups
a. The addition of the vaccine to the pills that were given to the volunteers
The basic structure of DNA is based on a. all these describe the DNA structure b. base-pairing of nucleotides c. double-helix model d. antiparallel strand
a. all these describe the DNA structure
What atom forms the backbone of almost all biological molecules? a. carbon b. nitrogen c. phosphorus d. hydrogen
a. carbon
When do organisms use anaerobic pathways to generate energy? When the Krebs cycle is moving too slowly When the cytoplasm is unavailable for cellular respiration When glucose is available as a reactant When there is not enough oxygen available to undergo aerobic cellular respiration
When there is not enough oxygen available to undergo aerobic cellular respiration
How is an anabolic pathway such as tryptophan synthesis regulated
When tryptophan is present, the operon is repressed
Which cellular function may be disrupted because of a malformation of the intermediate filaments? a. cell elasticity to withstand tensile forces b.vesicle transport c. muscle contraction d. cell movement
a. cell elasticity to withstand tensile forces
down syndrome
a condition of intellectual disability and associated physical disorders caused by an extra copy of chromosome 21.
For a given chemical reaction, a positive ΔG means a. energy needs to be added for the reaction to proceed. b. the reaction will never occur c. no energy needs to be added for the reaction to proceed. d. the reaction is spontaneous.
a. energy needs to be added for the reaction to proceed
A temporary oxygen deficit during strenuous exercise causes a muscle to a. ferment pyruvate to lactate. b. switch to aerobic glycolysis. c. synthesize more NAD+. d. synthesize muscle proteins in response to steroid hormone stimulation.
a. ferment pyruvate to lactate.
Which of the following correctly matches an organelle with its functions? a. Golgi - packaging secretory proteins b. Ribosome - manufacture of lipids c. Chloroplasts - aerobic respiration d. Lysosome - cellular movement
a. golgi- packaging secretory proteins
Each of the following is a function of membranes except a. information storage b. defining cell and organelle boundaries. c. cell—cell communication. d. regulation of transport
a. information storage
In the Diffusion and Osmosis lab, if a 0.06M solute concentration is considered hypotonic to potato cells, then water would be expected to move a. into the potato cell b. equally into and out of the potato cell c. out of the potato cell
a. into the potato cell
lac operon
a gene system whose operator gene which degrades lactose
How is genetic code degenerate and nonoverlapping
a particular amino acid can be specified by more than 1 triplet, the reading frame advanced three nucleotides at a time
Termination (Translation)
a stop codon in the mRNA is recognized by a protein release factor and the translational apparatus comes apart, releasing a completed polypeptide
meiosis
a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes
In a lab report, what is the section called toward the beginning of the report that is a summary of your report that states the goals, results, and main conclusions of your study? a. Abstract b.Introduction c. Table of Contents d. Discussion
a. Abstract
Which of the following is an informational macromolecule? a.DNA b. glucose c. ATP d. enzyme
a. DNA
Why are mitochondria so prevalent in skeletal muscle? a. Mitochondria provide energy for muscle contraction. b. More mitochondria are required in tissues where blood flow is restricted. c. Mitochondria produce energy anaerobically. d. Mitochondria are primarily involved in repairing damage accumulated during exercise.
a. Mitochondria provide energy for muscle contraction.
Kinesins act in a. Processive movement toward the microtubule plus end b. Generating a force to slide flagellar microtubules c. Movement along the microtubule toward it minus end d. Production of ATP
a. Processive movement toward the microtubule plus end
Feedback inhibition prevents cells from a. making products that are not needed by inhibiting the activity of enzymes in biosynthetic pathways. b. irreversibly inhibiting critical enzymes. c. destroying enzymes when they are needed in biosynthetic pathways. d. the harmful effects of enzyme activation by covalent modification of unneeded enzymes.
a. making products that are not needed by inhibiting the activity of enzymes in biosynthetic pathways.
All cells are considered to be open systems because a. the cell continually takes up energy from the environment. b. all reactions are exergonic. c. the cell cannot convert energy from one form to another. d. all cells are autotrophic.
a. the cell continually takes up energy from the environment
Enzyme saturation can be defined as a. the inability to increase reaction velocity beyond a finite upper limit. b.denaturation of an enzyme. c. inhibition of enzyme function by blocking the active site. d. the substrate concentration at which reaction velocity begins to increase.
a. the inability to increase reaction velocity beyond a finite upper limit.
Water moves across the plasma membrane into or out of a cell by osmosis when a. there is an equal solute concentration on both sides of the membrane b. it diffuses through the membrane toward a lower solute concentration. c.it diffuses through the membrane toward a higher solute concentration.
a. there is an equal solute concentration on both sides of the membrane
Movement of a newly synthesized protein from the endoplasmic reticulum to the Golgi apparatus would involve a _______________ vesicle and ______________ motor protein. a. transport; kinesin b. secretory; dynein c. transport; dynein d. endocytic; kinesin
a. transport; kinesin
cancers arise from
abnormalities of cell function
Which of these is not involved in the light harvesting reactions? antenna pigments absorb photons of light transfer of energy to an electron absorption of green light photoexcitation
absorption of green light
When DNA damage is severe, p53
activates genes resulting in apoptosis
DNA damage leads to ______ p53 gene
activiation
Which of these does not describe type of cell attachment in epithelial cells? adhesive glycoproteins attach cells to the matrix cells are sealed together so that molecules can only cross the cell layer by passing through the cells small passages between cells that allow ions to pass directly from one cell to another cadherin proteins interact with the extracellular portions of similar proteins on neighboring cells
adhesive glycoproteins attach cells to the matrix
Translocation
after the peptide bond forms, mRNA advances to bring the next codon into proper position
base modifying agents
agents react chemically with DNA to alter their structure
Which is not true of transposons
all humans have the same transposons
Many signal transduction pathways cause alterations in gene expression the switching off of gene expression all of these answer choices are correct increased gene expression
all of these answer choices are correct
The energy transduction reactions of photosynthesis convert solar energy into chemical energy in the form of _________ and _________. NADH, ADP NADP+, ATP NADPH, ATP NADP+, ADP
NADPH, ATP
If you had two alternative forms of a gene, how would you describe these forms and how would you describe your genotype? genes; heterozygous genes; homozygous alleles; homozygous alleles; heterozygous
alleles; heterozygous
elongation (translation)
amino acids are brought to the mRNA by tRNAs and are added one by one to a growing polypeptide chain.
Anabolic pathway of gene regulation
amount of enzyme produced by a cell usually correlates inversely with the concentration of end product of the pathway
Students determined the effect of sunlight on the rate of photosynthesis in Elodea. Elodea is a fresh water aquatic plant commonly found in north America. They had two set ups. Students placed an elodea plant in 200mL of fresh water in a beaker and placed it outside in direct sun. They called this plant, Plant A. Next they placed an elodea plant in 200 mL of fresh water in the same size beaker. But, they placed this plant in a dark closet. They called this plant, Plant B. The students were able to measure the oxygen bubbles produced by the plant. They found that plant A produced 6mm of bubbles and plant B only produced 2mm of bubbles.What is the independent variable for this experiment? amount of oxygen amount of sunlight amount of elodea rate of photosynthesis
amount of sunlight
most cells do not divide unless stimulated by
an external signal/growth factor
Most reactions involving NADP+ are ________ reactions, whereas most reactions involving NAD+ are ________ reactions. anabolic; catabolic both catabolic and anabolic; catabolic metabolic; anabolic catabolic; anabolic
anabolic; catabolic
what is the shortest phase of mitosis
anaphase
The ___ is found on the ___ which also carries the amino acid to the ribosome. anticodon/mRNA anticodon/tRNA codon/tRNA codon/rRNA
anticodon/tRNA
p53 disruption causes failure of
apoptosis
which of these is not a step in the process of cancer
apoptosis
inactive precursors
are activated by removal of sequences from one end of the protein
lymphoma
arise from cells of blood and lymphatic origin
trp operon
as concentration of tryptophan rises, it is useful if the cell turns off production of enzyme needed for tryptophan synthesis
What acts as a fluidity buffer to help the membrane resist change in fluidity due to temperature fluctuations? a. Saturated fatty acids. b. Cholesterol. c. Unsaturated fatty acids. d. Glycolipids
b. Cholesterol.
the table below shows three enzymes found in human body, and the temperature of their locations. Enzyme Body part Temperature (°F) Ptalyin Mouth 98.06 - 98.6 Pepsin Stomach 99.14 - 99.68 Trypsin Small intestine 99.14 - 99.68 How would a fever of 104°F most likely affect the activity of these enzymes? a. It would cause the enzyme to adapt to the new temperature. b. It could slow or stop enzyme function. c. It will change the genetic code of the enzyme. d. It would increase enzyme activity to fight the infection off faster.
b. It could slow or stop enzyme function.
What is not true about the Glucose Transporter (GLUT1) a. It can facilitate transport in either direction b. It uses active transport to move glucose c. It changes conformation to move glucose in or out of the cell d. It is an integral membrane protein
b. It uses active transport to move glucose
The site on an enzyme that will bind the substrate is called the a. allosteric site b. active site. c. activation site d. catalysis site
b. active site
Which of these is the best way to include controls? a. include only a positive control b. always include both negative and positive controls c. include only a negative control d. include both a positive and negative control, when possible
b. always include both negative and positive controls
The type of microtubules found in the flagella of a bacterial cell are referred to as a. prokaryotic microtubules b. axonemal microtubules c. cytoplasmic microtubules d. motility microtubules
b. axonemal microtubules
Each of the following statements about the citric acid cycle is true except a. oxidation leads to the formation of NADH and FADH2 b. each round of the citric acid cycle involves the entry of four carbons and the release of two carbon dioxides c. ATP is generated d. it metabolizes acetyl CoA
b. each round of the citric acid cycle involves the entry of four carbons and the release of two carbon dioxides
Directional pumping of protons during electron transport establishes a ____ cross the inner mitochondrial membrane a. oxidative phosphorylation gradient b. electrochemical proton gradient c. coenzyme oxidation gradient d. chemotrophic energy potential
b. electrochemical proton gradient
In the Enzyme Activity lab exercise, catalase was the a. substrate b. enzyme c. inhibitor d. product
b. enzyme
Which of these is not correctly matched up with its subunit? a. microtubules are composed of α-tubulin and β-tubulin b. intermediate filaments are composed of G-actin monomers bound together to form F-actin c. microfilaments are composed of G-actin monomers bound together to form F-actin d. intermediate filaments are made up of fibrous dimers of keratin
b. intermediate filaments are composed of G-actin monomers bound together to form F-actin
which of the following types of work involves a change in position of a cell or a cell structure? a. synthetic b. mechanical c. electrical d. concentration
b. mechanical
Viruses are composed of: a. only protein. b. nucleic acid and protein. c. only nucleic acid. d. DNA and carbohydrates.
b. nucleic acid and protein
Each of the following is a function of the rough endoplasmic reticulum except a. assembly of peptides b. steroid biosynthesis c. peptide folding d. formation of multimeric proteins
b. steroid biosynthesis
homologous recombination
Exchange of genetic information between homologous DNA molecules.
Which is not involved in translation?
DNA
Which of these is not important in translation
DNA
What is the central dogma of molecular biology?
DNA -> RNA -> Protein
A eukaryotic cell G2-M checkpoint assesses the status of nutrient abundance chromosome attachments to the spindle presence of growth factors DNA damage
DNA damage
Which best describes the process of transcription?
DNA is used to direct synthesis of mRNA
Which of these molecules would be unable to enter or exit the nucleus through the nuclear pores? DNA molecules needed for gene expression. Enzymes and proteins needed in the nucleus for DNA replication. mRNAs that need to be translated Components of ribosomes needed for translation
DNA molecules needed for gene expression.
_______ catalyze elongation of DNA chain
DNA polymerase
What proofreads newly made DNA?
DNA polymerases
genes
DNA segments that serve as the key functional units that determines phenotypic traits
T?F polymerase cant transcribe the same gene at one
FALSE many polymerase can transcribe at the same time
at the end of meiosis II,
Four haploid cells (gametes) each with half as many chromosomes as the original cell
Which of these is not an example of cell cycle control
G0
interphase includes
G1, S, G2
Transition points in cell cyle
G2-M ; Metaphase- Anaphase ; Restriction Point
A peptide bond: a. is a covalent bond between the functional R groups of adjacent amino acids. b. is a covalent bond between the NH group of one polypeptide and the CO group of an adjacent polypeptide that holds together multimeric proteins. c. is a covalent bond between the carboxyl carbon of one amino acid and the amino nitrogen of a second amino acid. d.is a noncovalent bond that dictates the tertiary structure of a protein.
c. is a covalent bond between the carboxyl carbon of one amino acid and the amino nitrogen of a second amino acid.
Which of these is not true about the primary structure of a protein? a. it dictates how the protein will fold. b. it is the linear sequence of amino acids that are linked together by hydrogen bonds. c. is not biologically active d. it is important for determining the secondary and tertiary structure of a protein.
c. is not biologically active
Which of these are not a component of animal cell membranes? a. glycoproteins b. cholesterol c. microfilaments d. phospholipids
c. microfilaments
The contraction of muscle cells involves a. axonemal dynein and flagella b. ATP and intermediate filaments c. myosin and actin microfilaments d. kinesin and microtubules
c. myosin and actin microfilaments
Pyruvate can be a substrate or product involved in each of the following except a. glycolysis. b. alcoholic fermentation. c. pyruvate is involved in all of these d. oxidation to acetyl coenzyme A
c. pyruvate is involved in all of these
The major difference between the mechanism of simple diffusion and facilitated diffusion is a. requirement of ATP b. movement of molecules down a concentration gradient c.the involvement of transport proteins d. movement of molecules against a concentration gradient
c.the involvement of transport proteins
In the Diffusion and Osmosis lab, what was the dependent variable you used to investigate osmosis? a. salt concentration b. temperature of the potato c.weight of the potato d. water concentration
c.weight of the potato
Positron emission tomography (PET) of a patient who has consumed the radiotracer fluorodeoxyglucose reveals tumors because the fluorodeoxyglucose labels only the normal tissue because cancer cells cannot metabolize glucose. the fluorodeoxyglucose labels cells killed by the PET treatment. any radioisotope accumulates in tumor cells. cancer cells accumulate fluorodeoxyglucose because they consume excessive amounts of glucose through aerobic glycolysis
cancer cells accumulate fluorodeoxyglucose because they consume excessive amounts of glucose through aerobic glycolysis
second step of metastasis
cancer cells are transported throughout the body via the circulatory system
Self sufficiency in growth signals
cancer cells escape need to be stimulated by growth factors through mutation
insensitivity to antigrowth signals
cancer cells evade such signals
Tissue Invasion and Metastasis
cancer cells gain the ability to invade neighboring tissues/metastasize to other parts of the body
Progression
cancer cells have lost all normal control of cell proliferation
first step of metastasis
cancer cells invade surrounding tissue and gain access to bloodstream
limitless replicative potential
cancer cells maintain the ability to divide indefinitely
third step of metastasis
cancer cells reinvade and grow at new location
Sustained angiogenesis
cancer cells stimulate angiogenesis to form their own blood supply- delivers O2 and nutrients
leukemia
cancer of white blood cells, proliferate in blood stream
carcinoma
cancerous tumor that arises from epithelial cells covering external and internal surfaces
malignant tumor
capable of invading surrounding tissues and spreading to distant parts of the body
Which represents the majority of cancers?
carcinomas
Inducible enzymes usually function in ___________ pathways.
catabolic
if DNA cannot be repaird, p53 activates genes needed to trigger
cell death by apoptosis
Which of the following would you expect to find in a prokaryotic cell? a. linear chromosomes b. cell membrane c. mitochondria d. membrane-bounded nucleus
cell membrane
Differntiation
cells are distinguished from each other based on difference in appearance and protein products
how do decondensed chromatin allow gene expression
chemical modification by histone
leptotene
chromosomes condense
What do restriction enzymes do
cleave specific DNA sequences in DNA
Which class of ECM molecule provides strength and flexibility? cadherin laminin proteoglycan collagen
collagen
Which is not a function of the cytoskeleton? a. movement of vesicles b. cell migration c. formation of mitotic spindles d. regulates permeability of cell membrane
d. regulates permeability of cell membrane
Which of the following is NOT considered a critical property of water in biological systems? a. cohesiveness b. temperature-stabilizing capacity c. solvent properties d.rapid liquid to gas transition
d.rapid liquid to gas transition
telophase
daughter chromosomes arrive at poles of spindle, chromosomes uncoil into interphase chromatin, nuclear envelope reforms
only _________ will allow gene expression
decondensed (unfolded) chromatin
what causes cancer?
defects in genes that regulate cell growth and division, environmental agents and lifestyle factors
normally p53 gene is expressed in the cell but is ____________ by _______ unless there is damage
degraded; MDM2
Transcription of Gene Expression
determined by transcription factors
sarcoma
develop from supporting tissues, bones, cartilage, fat, muscle
Lagging strand
discontinued, cut fragments (okazaki fragments) segments that continue along in a 3' to 5' segments
tumor arises when balance between cell division or death is
disrupted
Polarized cells are characterized by distinct apical and basolateral ends of the cell. being surrounded on all sides by a basement membrane. random orientation within a tissue. junctions only to ECM and not to other cells
distinct apical and basolateral ends of the cell.
UV radiation
dna altercation by triggering pyrimidine dimer formation
Initiation of Cancer
due to a few DNA mutations normal cells are converted into precancerous state and causes DNA damage.
DNA mutations can occur: during DNA replication. spontaneously. during DNA replication, spontaneously, or due to exposure to certain chemicals or radiation. due to exposure to certain chemicals or radiation
during DNA replication, spontaneously, or due to exposure to certain chemicals or radiation.
meiosis 1 nondisjunction
each gamete is N+1 or N-1
meiosis I
each homologous pair bind together during prophase to exchange some genetic information
polyribosomes maximize
efficiency
During which of the following is the most ATP produced in aerobic respiration? electron transport system glycolysis fermentation Krebs cycle
electron transport system
how is genetic code unambiguous
every codon has one meaning only
Catabolic pathways in Gene Regulation
exist to degrade specific substrates
Nuclear Export of gene expression
export to nuclei to the cytoplasm can be controlled, RNAs with defects in capping/splicing are not readily exported from the nucleus
Prophase
first and longest phase of mitosis, during which the chromosomes become visible and the centrioles separate and take up positions on the opposite sides of the nucleus
Alternative Splicing leads to
formation of mRNAs that code for either a secreted or membrane bound version of the protein
what type of mutation alters every amino acid after the point of mutation? sense mutation frameshift mutation missence mutation silent mutation
frameshift mutation
What type of cell undergoes meiosis?
gamete cells
Nondisjunction can be described as
gametes that have an extra chromosome
genotype
genetic makeup of an organism
What describes the genetic makeup of an individual?
genotype
Proteosomes
giant protein complexes that bind protein molecules and degrade them
Why is epidemiological data important to cancers?
helps identify lifestyle and environmental causes of cancer
What contributes to the diversity of the gametes and the end of meiosis
homologous recombination and independent assortment
when you have two of the same allele, you are described as
homozygous
what is a similarity between an inducible and a repressible system of gene expression
in both systems, the regulatory molecules function when they are bound to an operon
Ultraviolet (UV) light-treated bacteria would have increased DNA damage in the form of deamination of DNA bases. intercalation of the bases. pyrimidine dimer formation. base analog incorporation
pyrimidine dimer formation.
G2-M Transition
influenced by cell size, DNA damage, DNA replication
Restriction Point
influenced by growth factors, nutrients, cell size, DNA damage in animal cells, the ability to pass it is influenced by presence of extracellular growth factors
Translation rates can be controlled by
initiation factors and Translational Repressor
Stages of Transcription
initiation, elongation, termination
intercalating agent
insert themselves between adjacent bases which distorts the DNA
Dividing adult eukaryotic cells spend most of their time in which of the following? interphase telophase cytokinesis metaphase prophase
interphase
Which phase of cell cycle is the longest?
interphase
X Rays
ionizing radiation that removes electrons from molecules and generate highly reactive intermediates that damage DNA
DNA Methylation
is associated with inactive regions of genome and is the addition of a methyl group to certain cytosine bases in DNA, which can reduce gene activity typically used to repress gene expression
In DNA replication, the leading strand of DNA ________, while the other newly forming strand, called the lagging strand, ________. is synthesized in the 5' → 3' direction; the new DNA is synthesized in the 3' → 5' direction is synthesized as a continuous chain; the new DNA is formed in a series of short, discontinuous fragments is synthesized in the 3' → 5' direction; the new DNA is synthesized in the 5' → 3' direction is synthesized in a series of short, discontinuous fragments; the new DNA is synthesized as a continuous chain
is synthesized as a continuous chain; the new DNA is formed in a series of short, discontinuous fragments
metastasis
is the process where cancerous cells spread through the lymph and blood system to invade healthy cells.
Why is alternative splicing important?
it provides a way for our cells to make multiple proteins
Chromatin decondensation
key regulator of eukaryotic gene expression = physical state of the chromatin
example of Catabolic pathways in Gene Regulation
lac operon
Stages of prophase 1
leptotene, zygotene, pachytene, diplotene, diakinesis
Which of these is translated into protein
mRNA
______ brings polypeptide coding info to ribosomes
mRNA
Acetylation
makes chromatin more accessible to the transcriptional machinery
cancer refers to
malignancy
Which is true about genetic code
many amino acids are specified by more than one codon
how is genetic code degenerate
many of the amino acids are specified by more than one codon
what is an example of extremely slow growing tissue
mature nerve cells, muscle cells
_____ guides the synthesis of polypeptide chain
messenger RNA
During the phase of mitosis, sister chromatids are aligned in the center of the cell
metaphase
transposons
mobile repetitive DNA sequences that are not present in the same chromosomal location in all individuals of a species
frameshift mutation
mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide
After the neurotransmitters are detected by the postsynaptic neurons, changes in calcium concentration help with reuptake of neurotransmitters neurotransmitters are degraded rapidly a nerve impulse is initated in the presynaptic cell stimulation of the postsynaptic neuron is prolonged
neurotransmitters are degraded rapidly
What was produced in the spinach leaf chads showing that photosynthesis was occurring? carbon dioxide oxygen glucose water
oxygen
As elongation begins, start codon is located at
p site
________ gene is mutated in almost half of cancers
p53
What does NOT occur if DNA damage is identified during a cell cycle checkpoint? phosphorylation of p53 p53 is inactivated cell cycle arrest apoptosis
p53 is inactivated
What is the role of P53 in cancer
p53 mutations cause failure of apoptosis
The synaptonemal complex is complete and crossing over occurs during which stage of prophase I? zygotene leptotene pachytene diakinesis diplotene
pachytene
synapsis is complete in this stage
pachytene
alleles
pairs of determinants
Peptide bond formation
peptide bonds form between amino groups of the amino acid at A site and the carboxyl group of the amino acid at the P site
when there is DNA damage, p53 is _______________ which activates it
phosphorylated
When a plant's need to prevent water loss leads to increased oxygen concentration inside the leaf. photophosphorylation photorespiration. photoreduction photosynthesis.
photorespiration.
Paper chromatography was used in lab to separate plant pigments based on purity of the mixture molecular size their color polarities
polarities
a cluster of ribosomes
polyribosome
Alternative splicing
possible via mechanism allowing certain splice sites to be activated or skipped
Introns
primary transcript for most mRNA contain these and these sequences do not appear in mature DNA
Which of these is not true of sexual reproduction
produces offspring identical to parents
in dna damage is minor, p53 stimulates
production of enzymes involved in DNA repair
apoptosis
programmed cell death
DNA Polymerase
proofreads nucleotides during DNA replication copy DNA Exonuclease cleaves mistmatches
cells dont divide unless stimulated by
proper growth factor
During the ___ phase of mitosis, mitotic spindles first attach to sister chromatids
prophase
Which of the following correctly orders the stages of mitosis? telophase - prophase - metaphase - anaphase prophase - metaphase - anaphase - telophase metaphase - anaphase - prophase - telophase prophase - anaphase - metaphase - telophase
prophase - metaphase - anaphase - telophase
Posttranslational Control involves modification of
protein structure, function and degradation
Which of these examples of gene regulation is correctly paired
proteosomes/ post translational control
Which RNA is most abundant?
rRNA because it is always making protein
Which incorrectly matches the molecule with its movement through nuclear pores
rRNA enters the nucleus
each haploid contains a ________ mixture of maternal and paternal chromosomes
random
Which type of signaling pathway is used by VEGF in angiogenesis? G protein-coupled receptor ligand gated ion channel receptor tyrosine kinase
receptor tyrosine kinase
RNA Processing and Nuclear Export of Gene Expression
regulation of RNA splicing allows cells to create a variety of different mRNAs from the same pre-MRNA
What recognizes stop codons triggering termination of polypeptide synthesis? mRNAs tRNAs promoters release factors
release factors
What terminates the polypeptide synthesis?
release factors (STOP codon)
you are studying a eukaryotic gene whose initial transcript is 1500 nucleotides in length. The mature mRNA derived from the gene is 1200 nucleotides in length. What is the most probable reason for the discrepancy? removal of introns removal of exons mRNA breakage a mutation that results in a shorter product
removal of introns
Base excision repair is used to fix double-strand DNA breaks. remove single damaged bases. remove intercalating agents and single damaged bases. remove intercalating agents.
remove single damaged bases
base analogues
resemble nitrogenous bases and are incorporated into DNA
Transfer RNA
responsible for bringing amino acids to ribosomes during translation
Ribosomal RNA
responsible for enzymatically linking amino acids to form polypeptide
Which is not part of the structure of DNA Phosphate gorup NItrogenouse base ribose sugar deoxyribose
ribose
Most mRNA are read by MANY _______ simultaneously
ribosomes
Continuous carbon assimilation in the Calvin cycle is made possible by the regeneration of 3-phosphoglycerate. glyceraldehyde-3-phosphate. ribulose-1,5-bisphosphate glycerate-1,3-bisphosphate
ribulose-1,5-bisphosphate
metaphase
second phase of mitosis, during which the chromosomes line up across the center of the cell
what leads to random assortment of alleles in meiosis 1?
segregation and independent assortment of homologous chromosomes
DNA Replication is conservative dispersive semiconservative irregular
semiconservative
DNA is ______ meaning that there is one newly synthesized strand and one old strand
semiconservative
What is the purpose of Meiosis II
separate sister chromatids
Exons
sequences that appear in final mRNA
example of base pair substitution
sickle cell anemia
cells circumvent this altering ______, creating a constant signal to divide
signaling pathway
defects in _______, _______, ______ contribute to cancer
signaling pathway, cell cycle arrest, apoptosis
Which of these mutations does not affect the protein product
silent mutation
operons
single promotor that controls genes that code for proteins
Following DNA replication, the attached copies of each chromosome are called ___. Centrosomes Centromeres Sister Chromatids Chromosomes
sister chromatids
replicated DNA is referred to as
sister chromatids
posttranslational processing
sometimes whole blocks of Amino Acids are removed from polypeptide synthesized as an inactive precursor
genetic locus
specific location of a gene on a chromosome
g2 phase
stage of interphase in which cell duplicates its cytosol and organelles and final prep is made for early mitosis
what is an example of cells that need to be continuously divided to replace their old ones
stem cells, sperm formation
the main shared feature of promoting agent is the ability to
stimulate cell proliferation
Biosynthesis of starch occurs in the chloroplast intermembrane space. thylakoid lumen. cytosol. stroma.
stroma.
The Calvin cycle occurs in the chloroplast thylakoid lumen. outer membrane. thylakoid membrane. stroma.
stroma.
posttranslational mechanisms include
structural altercations that influence protein function guiding of protein folding targeting to specific locations Interaction with regulatory molecules
tetrad
structure containing 4 chromatids (2 sister chromatids=2 chromosomes) that forms during meiosis
When transcription of beta galactosidase is turned on only when lactose is present
substrate induction
failure of apoptosis causes
survival and reproduction of cells with DNA damage
zygotene
synapsis begins, synaptonemal complex forming
pachytene
synapsis complete, crossing over
diplotene
synaptonemal complex disappears, chiasma still present
Which of these binds to both amino acids and RNA
tRNA
Which of these is correctly paired
tRNA/anti-codon
What is not involved in termination of polypeptide synthesis
tRNAs
During the ___ phase of mitosis, cytokinesis also occurs
telophase
Which does not contribute to cancer
the ability of the cells to undergo apoptosis
Which is not involved in transcription
the coding strand of the DNA
initiation of translation
the components of the translational apparatus come together with an mRNA and a tRNA carrying the first amino acid binds to start codon
Signaling crosstalk is described as inhibition of second messenger pathways by receptor binding hormones acting over long distances one receptor binding a growth factor to activate gene transcription the integration of multiple signaling pathways
the integration of multiple signaling pathways
invasion of cancer
the migration and penetration of cancerous cells into neighboring tissue
Leading strand
the new complementary DNA strand synthesized continuously along the template strand toward the replication fork in the mandatory 5' to 3' direction
In the fermentation lab using baker's yeast and sucrose, the dependent variable was the production of carbon dioxide the production of oxygen the production of alcohol the production of lactic acid
the production of carbon dioxide
coding strand
the strand of DNA that is not used for transcription and is identical in sequence to mRNA, except it contains uracil instead of thymine
Which statement is true about trp operon? the trp operon codes for proteins needed for tryptophan sythesis the trp operon codes for proteins that metabolize tryptophan the trp operon activates only in the presense of tryptophan the trp operon can be induced when tryptophan is present
the trp operon codes for proteins needed for tryptophan synthesis
Which of the following statements regarding the watson-crick model of DNA is false? the two DNA strands are antiparallel the two DNA strands are held together by covalent bonding between bases on opposite strands the two DNA strands form a double helix The backbone consists of alternating sugars and phosphates
the two DNA strands are held together by covalent bonding between bases on opposite strands
what can happen to proteins after translation
they can have amino acids removed from polypeptides they can have sugras added they can be secreted
Which is not true of adrenergic hormones? they are produced by the adrenal glands they increase blood flow to muscles they stimulate glycolysis in muscle they stimulate secretion of insulin by the pancreas
they stimulate secretion of insulin by the pancreas
How do negative and positive regulation in bacteria differ?
transcription is reduced in negative regulation when the promoter is bound
methylation of promoter region can block access of proteins needed for transcription and the net effect is
transcriptional repression
According to the central dogma, the process by which information in an RNA molecule is used to direct the synthesis of a polypeptide is called transcription. translation. transduction. replication
translation
replicative transposons (Copy and paste)
transposon is copied from the current site and the new copy inserted at the new site
Conservative transposon (cut and paste)
transposon is excised from the original site and more to a new site in the genome
example of end product repression
trp operon
T/F hormones and growth factors may inadvertently behave as tumor promoters
true
What do you have after Meiosis 1
two haploid daughter cells
______ Targets proteins for the degradation of proteosomes
ubiquitin
Evasion of Apoptosis
when cells avoid programmed death due to mutation of p53 gene
Although pyruvate is the end product of glycolysis and no more ATP is generated by fermentation of pyruvate to ethanol, yeast produce ethanol under anaerobic conditions because a. pyruvate to ethanol fermentation decreases deleterious CO2 levels. b. transfer of electrons from NADH to pyruvate to make ethanol regenerates NAD+, which is necessary for new rounds of glycolysis to proceed. c. electrons (and protons) are then added to ethanol to make lactate. d. pyruvate export requires more energy than ethanol export
b. transfer of electrons from NADH to pyruvate to make ethanol regenerates NAD+, which is necessary for new rounds of glycolysis to proceed.
Chemical mutations of DNA
base analogues base modifying Intercalating agent
what is not involved in the spread of cancer cells
benign tumor formation
inducible enzyme in lac operon
beta - galactosidase
Substrate Induction of lac operon
beta galactosidase is only needed when lactose is present
RNA chain elongation involves
binding, peptide bond Formation and Translocation
This type of tissue consists of a rigid matrix containing a small number of interspersed cells. bone epithlium cartilage connective
bone
Which of these products of the Krebs cycle are oxidized in the Electron Transport System? a. NADH and carbon dioxide b. ATP c. NADH and FADH2 d. carbon dioxide and ATP
c. NADH and FADH2
According to the Cell Structure lab, what is not true of all cells a. all cells pass along their hereditary material to offspring b. all cells come from preexisting cells c. all cells contain cell walls d. all cells are surrounded by a cell membrane
c. all cells contain cell walls
NAD+ a. releases a phosphate to become NADH. b. is the reduced form produced by glycolysis. c. is a coenzyme acceptor of electrons and a hydrogen ion. d. is an electron source for biological oxidation reactions.
c. is a coenzyme acceptor of electrons and a hydrogen ion.
Of the 64 possible codons, how many code for amino acids?
61
What is the role of the lysis buffer in DNA isolation? To precipitate out the DNA To make the DNA visible To help the DNA cross the cell membrane To break apart the cell membranes releasing the DNA
To break apart the cell membranes releasing the DNA
differentiated cells are produced from
groups of immature, nonspecialized cells in cell differentiation
recombination
(genetics) a combining of genes or characters different from what they were in the parents
At the end of Meiosis I, each cell produced contains __________ haploid set of replicated chromosomes with _____ sister chromatid
1 ; 2
Hallmarks of Cancer
-Self sufficiency in growth signals -Insensitivity to antigrowth signals -Evading apoptosis -Limitless replicative potential -Sustained angiogenesis -Tissue invasion and metastasis
Main Levels of Gene Expression
1. Genome 2. Transcription 3. RNA Processing and Nuclear export 4. Translation 5. Posttranslation
Mechanism of translation
1. Initiation 2. Elongation 3. Termination
Steps of metastasis
1. cancer cells invade surrounding tissue and gain access to bloodstream 2. they're transported throughout the body 3. they leave the bloodstream and establish new metastatic tumors in various organs
how do carcinogens modify DNA
1. crosslink b/w two strands of double helix 2. creating chemical links between adjacent bases 3. hydroxylating or removing individual bases 4. causing breakage in one or both DNA strands
steps of cancer progression
1. normal cells 2. early benign tumor 3. intermediate benign tumor 4. late benign tumor 5. localized cancer 5. invasion/metastasis
If an diploid organism has 8 chromosomes, how many chromosomes will be in each of the daughter cells at the end of meiosis? 4 2 8 16
4
meiosis produces
4 haploid cells with 23 chromosomes
How much of the human genome is composed of transposon
45%
DNA grows in the _______ direction
5' to 3'
mRNA reads in what direction
5' to 3'
Base pair insertion
A gene mutation in which one or more nucleotides are added to a DNA sequence.
Silent Mutation
A mutation that changes a single nucleotide, but does not change the amino acid created.
Nonsense mutation
A mutation that changes an amino acid codon to one of the three stop codons, resulting in a shorter, premature termination of translation and usually nonfunctional protein.
ubiquitin
A protein that attaches itself to faulty or misfolded proteins and thus targets them for destruction by proteasomes
elongations begins at tRNA w/ anticodon complementary to second codon binds to
A site
peptide bonds form between amino groups fo the amino acid at
A site
Rubisco catalyzes the joining of carbon dioxide with RuBP during carbon fixation. In an experiment, researchers apply a toxin to a plant cell that inhibits Rubisco. Which of the following explains the most likely effect this toxin will have on the Calvin cycle? Carbon and oxygen will not be released after the breakdown of carbon dioxide. Carbon dioxide will not be converted into carbohydrates. Excited electrons will not be transferred across the electron transport chain. ATP synthase will not catalyze the formation of ATP on the thylakoid membrane.
Carbon dioxide will not be converted into carbohydrates.
Which is not involved in Watson and Crick Model of DNA
Covalent bonding between bases links the two strands
During cell communication in the nervous system, chemical messengers called neurotransmitters travel between neurons. As they travel, neurotransmitters send messages from one neuron to another. Which of the following best describes the role of neurotransmitters in neuron-to-neuron communication? Neurotransmitters are local regulators that allow neurons to communicate over long distances. Neurotransmitters are long-distance signaling molecules that allow neurons to communicate over short distances. Neurotransmitters are local regulators that allow neurons to communicate over short distances. Neurotransmitters are long-distance signaling molecules that allow neurons to communicate over long distances.
Neurotransmitters are local regulators that allow neurons to communicate over short distances
what is not part of DNA replication
Okazaki fragments make of the leading strand (they make up the leading strand)
peptide bonds form between amino groups of the amino acid at A site and the carboxyl group of the amino acid at the
P Site
What technique is used to amplify a large amount of DNA
PCR
Anaphase
Phase of mitosis in which the chromosomes separate and move to opposite ends of the cell
Which of the following molecules can be considered a final product in the flow of information within a cell? DNA protein RNA Protein or RNA can be the final product of a gene.
Protein or RNA can be the final product of a gene.
When is DNA replicated
S phase
Which of these does not describe receptor binding? Binding between receptor and ligand is similar to the binding of enzyme to its substrate. Ligand binding of the receptor can trigger additional signals within the cell resulting in gene expression. Synthetic ligands can be made which bind more tightly than the real ligand Saturation cannot be reached when most of the receptors are occupied by ligands.
Saturation cannot be reached when most of the receptors are occupied by ligands.
Which of the following is true about mitosis or meiosis? Sister chromatids are separated in anaphase II of meiosis. Sister chromatids are separated in metaphase I of meiosis. Homologous chromosomes are separated in anaphase II of meiosis. Homologuous chromosomes are separated in anaphase of mitosis
Sister chromatids are separated in anaphase II of meiosis.
origin of replication
Site where the replication of a DNA molecule begins, consisting of a specific sequence of nucleotides.
template strand
The DNA strand that provides the template for ordering the sequence of nucleotides in an mRNA transcript.
G1 phase
The first gap, or growth phase, of the cell cycle, consisting of the portion of interphase before DNA synthesis begins.
primary transcript
The initial mRNA transcript that is transcribed from a protein coding gene. Also called pre-mRNA.
What did Edwin Chargaff observe about the base composition of DNA
The number of A= the number of T
S phase
The synthesis phase of the cell cycle; the portion of interphase during which DNA is replicated.
Each of the following is true about endocrine hormones except Their life span may range from a few seconds to many hours They act as antagonists They travel via the circulatory system They are produced far from their target tissues
They act as antagonists
which of these is a mutation due to UV radiation
Thymine dimers
Which of these lab techniques was NOT used in the Molecular Cloning lab? PCR Gel electrophoresis Western blot analysis Restriction enzyme digestion
Western blot analysis
How do you describe a gene that is expressed all the time
constitutive
genes that are expressed all the time are
constitutive
An enzyme a. gets used up in the process of catalyzing a chemical reaction. b. increases the activation energy of a chemical reaction. c. does not change the rate of a reaction. d. binds substrates in a manner that facilitates the formation of product
d. binds substrates in a manner that facilitates the formation of product
During telophase _____ also takes place
cytokinesis
What is the final power of magnification if the ocular lens is 10 x and the objective is 10x? a. 1000x b. 10x c. 20x d. 100x
d. 100x
Directional pumping of protons across the inner mitochondrial membrane during electron transport is important for the synthesis of a. NADH b. water c. carbon dioxide d. ATP
d. ATP
What concept explains why cells are so small? a. Cell radius ratio b. Metabolic ratio. c. They are made up of small molecules d. Surface to volume ratio
d. Surface to volume ratio
Which of the following polymers is mismatched with its monomer? a. polypeptides; amino acids b. DNA; nucleic acids c. enzyme; amino acids d. glycogen; monosaccharides
d. glycogen; monosaccharides
Promotion of Cancer
gradual process requiring prolonged or repeated exposure to a promoting agent
Defects in meiosis lead to
nondisjunction
diakinesis
nuclear envelope fragments, chromosomes complete condensing, tetrads ready for metaphase.
which fo these does not describe DNA packaging in eukaryotes
nucleosomes are the last step of DNA packaging
Transcription occurs in
nucleus
mRNA must be exported from _______ to ________ during translation
nucleus; cytoplasm
How many times is DNA replicated for meiosis
once
mitosis and meiosis undergo cell division
once
How many of the G3P molecules generated by the Calvin cycle are used for biosynthesis of sucrose? one six three two
one
mitosis
one cell divides into two identical diploid cells
meiosis II nondisjunction
one is n+1, n-1, 2 are n
dominant allele
one whose trait always shows up in the organism when the allele is present
