BIO Final Exam

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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


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