comprehensive final multiple choice Flashcards
a scientific theory is:
a: a suggested explanation that accounts for observations.
b: a way to organize how we think about a problem.
c: a concept that is supported by experimental evidence that explains the facts in an area of study.
d: a way to understand a complex system by reducing it to its working parts.
c: a concept that is supported by experimental evidence that explains the facts in an area of study.
matter is composed of:
a: atoms
b: energy
c: mass
d: molecules
a: atoms
when atoms gain or lose electrons, they can become negatively or positively charged. These charged atoms are known as:
a: ions
b: isomers
c: unstable atoms
d: isotopes
a: ions
sanai was monitoring the oil spill in the Gulf of Mexico from an oil tanker. From her observations, she noted that the oil was moving in large patches through the water. The oil did not appear to dissolve into the water. Why did the oil not dissolve into the water?
a: hydrophobic interactions
b: surface tension
c: sea water acts as a solvent
d: water forms hydration shells
a: hydrophobic interactions
a chemist adds a chemical to pure water and there is a 100-fold increase in the concentration of hydrogen ions. What is the best approximation of the new pH value?
a: 0
b: 5
c: 7
d: 9
b: 5
the atomic number of an element is equal to the number of:
a: neutrons only.
b: neutrons plus electrons.
c: protons only
d: protons plus electrons.
e: protons plus neutrons.
c: protons only
water molecules are attracted to each other due to the opposite charges created by partial charge separations within the molecules. These attractions are called:
a: peptide bonds.
b: covalent bonds
c: ionic bonds.
d: hydrogen bonds
e: double bonds.
d: hydrogen bonds (correct)
water is most dense and thus heaviest at 4°C. At 0°C, ice forms and can float on liquid water. Suppose ice was more dense then water at 0°C. What would happen in a lake at this temperature?
a: the ice would cover the surface of the aquatic system and would never melt.
b: Ice would not form because solids are always less dense than liquids.
c: The cold temperatures and the subsequent ice formation would prevent hydrogen bonds from forming between the water molecules, thus causing the existing ice crystals to become disassociated from each other.
d: The ice would cover the bottom of the aquatic system and would build up in layers over time.
d: The ice would cover the bottom of the aquatic system and would build up in layers over time.
you recently discovered a new element, and find that this particular element has one electron in its outer energy level. What do you expect will happen to an atom of this element if placed in water?
a: it will lose an electron forming a negative ion.
b: It will gain an electron forming a negative ion.
c: It will gain an electron forming a positive ion.
d: It will lose an electron forming a positive ion.
d: It will lose an electron forming a positive ion.
the high heat of vaporization of water helps you to feel cooler when you sweat because the transition of water from a liquid to a gas requires a _________blank of energy to break hydrogen bonds. The energy is _________blank from heat produced by your body, thus helping to lower the surface temperature of your body.
a: release; released
b: release; obtained
c: input; obtained
d: input; released
c: input; obtained
egg whites consist primarily of water and the protein albumin. When you fry an egg, why does the egg white turn from an opaque, thick liquid to a white, solid substance?
a: the protein becomes denatured
b: the protein becomes hydrolyzed
c: the protein becomes dissociated
d: the protein becomes dehydrated
a: the protein becomes denatured
the digestive enzyme pepsin works in the acidic environment of the stomach to hydrolyze peptide bonds. As a result, pepsin affects which macromolecule?
a: DNA molecule
b: lipid
c: carbohydrate
d: protein
d: protein
which of the following is a unique feature of viruses that separates them from bacteria?
a: they cannot exist outside of a host cell
b: They have different nucleotide bases in their hereditary material
c: They are generally much smaller
d: They lack proteins
c: They are generally much smaller
each of the following facts state the major significance of the element carbon in the human body EXCEPT..?
a: carbon is the main component of water
b: carbon-containing molecules can form rings, branches, or coils
c: carbon can form bonds with four different atoms
d: carbon forms the backbone of all organic molecules
a: carbon is the main component of water
proteins are polymers formed of structural units called:
a: fatty acids
b: nucleotide bases
c: amino acids
d: phosphate groups
c: amino acids
In a phospholipid molecule, the “head” is _____.
In a phospholipid molecule, the “tail” is _____.
a: hydrophilic
b: hydrophobic
macromolecules that are used by all organisms to store hereditary information are called:
a: carbohydrates
b: DNA molecules
c: lipids
d: proteins
b: DNA molecules
what is the best reason why people are vaccinated once a year for influenza?
a: the immune system only “remembers” vaccines for several months
b: the vaccine is removed by the body after 12 months
c: the virus binds to all of the vaccine after a few months
d: mutations cause antigenic drift in HA and NA proteins
d: mutations cause antigenic drift in HA and NA proteins
these biological compounds are nonpolar and insoluble in water:
a: nucleic acids
b: lipids
c: proteins
d: carbohydrates
b: lipids
humans are unable to derive metabolic energy from cellulose because:
a: cellulose contains very little chemical energy
b: cellulose is not part of a normal diet
c: cellulose digesting enzymes are absent from the human gut
d: cellulose does not taste good
c: cellulose digesting enzymes are absent from the human gut
the covalent bonds connecting monomer units in sugars can be broken by the addition of a water molecule. This reaction is referred to as:
a: a hydration reaction
b: a hydrolysis reaction
c: a dehydration reaction
d: an oxidation-reduction reaction
b: a hydrolysis reaction
a person writes a malicious computer program and embeds it in an email. When someone receives the email, the program makes copies of itself on their hard drive, and also sends new emails with the program to other recipients. However, if a user has installed security software, it blocks the email.
Match the features of the computer “virus” to the similar features of a biological virus.
host cell (computer)
viral genome (malicious program)
immune system (security software)
viral spike protein (email)
in a(n) ________ cell, the DNA is not enclosed in a membrane.
in a(n) ________ cell, most of the DNA is located in the nucleus.
a: prokaryotic
b: eukaryotic
which of the following intercellular junctions forms a seal around the adjacent epithelial cells of the small intestine to prevent partially digested molecules from passively leaking into the abdominal cavity?
a: gap junctions
b: desmosomes
c: plasmodesmata
d: tight junctions
d: tight junctions
The cytoplasmic space in cells is occupied by many diverse membrane-bound structures with specific cellular functions called ___________.
a: organelles
b: chromosomes
c: extracellular matrix
d: cilia
a: organelles
The semifluid matrix that surrounds organelles in a cell is called the __________.
a: stroma
b: ribosome
c: cytoplasm
d: nucleolus
c: cytoplasm
Integrins are glycoproteins that help link the cytoskeleton and the _______.
a: nucleus
b: cytoplasm
c: extracellular matrix
d: cell wall
c: extracellular matrix
the Central Dogma of biology can be stated asa:
a: DNA→ Proteins→ RNA
b: RNA→ DNA→ Proteins
c: DNA→ RNA→ Proteins
d: Proteins→ RNA→ DNA
c: DNA→ RNA→ Proteins
the genetic code uses ____ nucleotide(s) to specify one amino acid.
a: 64
b: 2
c: 1
d: 3
d: 3
brain cells and muscle cells contain the same DNA in their nuclei. The main reason they differ in their structure and function is because they _____.
a: contain different chromosomes
b: express different genes
c: use different genetic codes
d: have unique ribosomes
b: express different genes
which of the following characteristics is directly related to the coding of a single amino acid during the process of translation?
a: the three-base sequence of mRNA
b: the anticodon sequence of the tRNA
c: the base pair complementarity of the DNA and RNA
d: more than one codon can specify the addition of the same amino acid
a: the three-base sequence of mRNA
rank the following DNA molecules in order based on their size in length, starting with the smallest (#1) and ending with the largest (#4)
(1) nucleotide base
(2) codon
(3) gene
(4) chromosome
in preparation for the translation step of gene expression, pre-mRNA processing may involve all of the following except
a: addition of a 5’ cap
b: pre-mRNA splicing by the spliceosome
c: removal of exons from the pre-mRNA
d: addition of a 3’ poly-A tail
c: removal of exons from the pre-mRNA
given the sentence “THE FAT CAT ATE THE RED RAT,” which of the following would represent a frameshift mutation?
a: THE CAT ATE THE RED RAT
b: THE FAC ATA TET HER EDR AT
c: THE FAT CAT ATE THE RED RAT
d: THE FAT RAT ATE THE RED CAT
b: THE FAC ATA TET HER EDR AT
which of the following protein classes are not found as membrane proteins?
a: enzymes
b: receptors
c: hormones
d: transport channels
c: hormones
you are cooking beans over a campfire. By the light of the fire, you read that one serving of beans is 120 calories. After eating the beans, you go for a hike along a stream. All of the items described here have energy. Identify the form of energy each contains:
potential energy: firewood and beans
kinetic energy: moving water, hiking, and flames
a current problem in modern medicine is the development of drug resistant mutations. This occurs when a mutation arises in a disease-causing microbe making it resistant to a drug and thus rendering the drug useless. Many drugs are competitive inhibitors of specific enzymes, and the drug-resistant mutations prevent the binding of the drug. These types of mutations, in addition to preventing competitive inhibitor binding, can also reduce the activity of the enzyme. Why is that the case?
a: these mutations most likely change the shape of the active site of the enzyme
b: these mutations lower the activation energy of the reaction catalyzed by the enzyme
c: binding to the competitive inhibitor is essential for the function of the enzyme
d: these mutations most likely affect an allosteric site on the enzyme
a: these mutations most likely change the shape of the active site of the enzyme
a drug binds to the active site of an enzyme. If it is bound to the active site of the enzyme, it prevents substrate binding. This drug would be considered a(n) ______.
a allosteric inhibitor
b: noncompetitive inhibitor
c: allosteric activator
d: competitive inhibitor
d: competitive inhibitor
a scientist performs an experiment in which they create an artificial cell with a selectively permeable membrane through which only water can pass. They inject a 5M solution of glucose into the cell and then place the cell into a beaker containing 10M glucose. What effect do you expect to observe?
a: water moves out of the cell
b: water moves into the cell
c: glucose moves out of the cell
d: glucose moves into the cell
a: water moves out of the cell
the chemistry of living systems representing all chemical reactions is called ________.
a: metabolism
b: catabolism
c: thermodynamics
d: anabolism
a: metabolism
the fluid mosaic model is best described as ____________.
a: the cell membrane is composed of a phospholipid bilayer between two layers of globular proteins
b: the cell membrane is composed of lipids and proteins
c: the cell membrane is composed of a phospholipid bilayer but the polar ends of the phospholipid molecules were reversed
d: the cell membrane is composed of a phospholipid bilayer with globular proteins actually inserted into the bilayer
d: the cell membrane is composed of a phospholipid bilayer with globular proteins actually inserted into the bilayer
the Law of Thermodynamics that states that energy cannot be created or destroyed is __________.
the Law of Thermodynamics that states that increases in entropy are favored is __________.
a: first law of thermodynamics
b: second law of thermodynamics
on the outer surface of the plasma membrane there are marker molecules that identify the cell type. Often these molecules are ____________.
a: carbohydrate chain
b: nucleotide bases
c: amino acids
d: ATP
a: carbohydrate chain
oxidation and reduction reactions are chemical processes that result in a gain or loss of _____________.
a: water
b: atoms
c: protons
d: electrons
d: electrons
why do we have storage macromolecules, such as fats, in our bodies?
a: human cells can directly capture the energy of sunlight through photosynthesis and store it as macromolecules such as fats.
b: we can break down these macromolecules to provide energy for the endergonic reactions in our bodies.
c: macromolecules, such as fats, are a convenient way to store kinetic energy.
d: breaking down macromolecules, such as fats, is an endergonic process.
b. we can break down these macromolecules to provide energy for the endergonic reactions in our bodies.
how does an electron transport chain lead to the generation of ATP in the light-dependent reactions of photosynthesis?
a: the electron transport chain directly phosphorylates ADP to make ATP
b: the electron transport chain directly absorbs light energy and transforms it into the chemical energy of ATP
c: the movement of electrons down the electron transport chain directly activates ATP synthase
d: the movement of electrons down the electron transport chain drives protons (H+) across the thylakoid membrane, generating an electrochemical gradient that is used to make ATP
d: the movement of electrons down the electron transport chain drives protons (H+) across the thylakoid membrane, generating an electrochemical gradient that is used to make ATP
during cell respiration, the last carrier protein transfers a pair of electrons to _____.
a: water
b: pyruvate
c: NADH
d: oxygen
d: oxygen
in green plants, what is the sequence of photosystems, and what does each photosystem produce?
a: photosystem I -> NADPH production -> Photosystem II -> ATP production
b: photosystem I -> ATP production -> Photosystem II -> NADPH production
c: photosystem II -> ATP production -> Photosystem I -> NADPH production
d: photosystem II -> NADPH production -> Photosystem I -> ATP production
c: photosystem II -> ATP production -> Photosystem I -> NADPH production
- cells use ___ to power most cellular activities that require work.
- ATP is most often used to drive an ___ reaction.
- in substrate-level phosphorylation, ATP is formed when a ______ is transferred directly to ADP.
- ATP is synthesized by _____ in oxidative phosphorylation.
- ATP synthesis is driven by ______ reactions.
a: phosphate group
b: exergonic
c: ATP synthase
d: ATP
e: endergonic
- (d) ATP
- (e) endergonic
- (a) phosphate group
- (c) ATP synthase
- (b) exergonic
how do electrons enter the electron transport chain?
a: by the reduction of NADH
b: by the oxidation of water
c: by the oxidation of NADH
d: by the reduction of oxygen
c: by the oxidation of NADH
- a green pigment likely ____ green light.
- chlorophyll ____ and blue wavelengths of light best.
- a 430nm pigment likely absorbs ____ light.
- carotenoids absorb light in the blue and _____ region of the spectrum.
a. blue
b. green
c. absorbs
d. reflects
- (d) reflects
- (c) absorbs
- (a) blue
- (b) green
during which stage(s) of cell respiration is there a release of CO2?
krebs cycle
which of the following metabolic pathways is common to both fermentation and cell respiration?
a: citric acid (Krebs) cycle
b: pyruvate oxidation
c: glycolysis
d: oxidative phosphorylation
c: glycolysis
in the light-dependent reactions of photosynthesis, the electrons passed down through the electron transport system are ultimately obtained from _____.
a: sunlight
b: carbon dioxide
c: glucose
d: water
d. water
if a plant lacked all pigments (e.g., chlorophyll a, chlorophyll b, carotenoid), how would this affect photosynthesis?
a: photosynthesis would not be affected at all
b: the Calvin cycle would run faster, generating more glucose
c: the Calvin cycle would not run in the absence of pigments
d: the light-dependent reactions would generate glucose in the absence of pigments
c: the Calvin cycle would not run in the absence of pigments
cyanide is a poison that inhibits the enzyme cytochrome oxidase, preventing the transport of electrons from cytochrome c to oxygen. Suppose an animal ingests cyanide. Select the statement that is true regarding cell respiration in cells in this animal shortly after cyanide ingestion.
a: ATP will not be generated during glycolysis
b: NADH will not be generated by the citric acid cycle
c: NADH will be abundant and NAD+ will be depleted
d: Acetyl-CoA will undergo glycolysis
c: NADH will be abundant and NAD+ will be depleted
the synthesis of ATP via a proton (H+) gradient is called _____.
a: substrate-level phosphorylation
b: glycolysis
c: chemiosmosis
d: citric acid (Krebs) cycle
c: chemiosmosis
as the two strands of DNA are unraveled, which enzyme relieves the strain on the two strands?
a: DNA ligase
b: DNA polymerase
c: DNA gyrase
d: RNA primer
c: DNA gyrase
the site where the two original DNA strands separate and active replication occurs is called the
a: replication fork.
b: replisome.
c: primosome.
d: lagging strand.
a: replication fork.
what are the two characteristics that best describe the structure of the DNA molecule?
double helix
&
antiparallel
if a short sequence of DNA is 5’ AATTGCCGT 3’, its complement is
a: 5’ AAAACGCCA 3’.
b: 3’ TTAACGGCT 5’.
c: 3’ TTAAGCCGA 5’.
d: 3’ TTAACGGCA 5’.
d: 3’ TTAACGGCA 5’.
which enzyme adds new nucleotides to the end of a growing strand?
a: helicase
b: DNA gyrase
c: DNA ligase
d: DNA polymerase
d: DNA polymerase
________blank is the genetic material for all cellular organisms and some viruses.
a: DNA
b: Chromatin
c: Protein
d: RNA
a: DNA
because the two strands of a DNA molecule are _________blank to each other, either one can be used as a template to reconstruct the other.
a: identical
b: complementary
c: bound
d: antiparallel
b. complementary
DNA primase…?
a: creates a short RNA primer that is complementary to a DNA template.
b: creates a short DNA template that is complementary to an RNA primer.
c: creates a short DNA primer that is complementary to an RNA template.
d: creates a short DNA primer that is complementary to a DNA template.
a: creates a short RNA primer that is complementary to a DNA template.
- The ____ checkpoint is the primary point of the cell cycle that is influenced by external signals.
- The _____ checkpoint ensures that all of the chromosomes are attached to microtubules.
- The ______ checkpoint assesses whether DNA is damaged and also whether DNA replication has completed.
- Passage through checkpoints is controlled by ____enzymes.
a. cdk
b. G2/M
c. spindle
d. G1/S
- (d) G1/S
- (c) spindle
- (b) G2/M
- (a) cdk
during replication, which enzyme unwinds the DNA double helix?
a: DNA primase
b: DNA ligase
c: DNA helicase
d: DNA gyrase
c: DNA helicase
what is the sequence of events in a typical cell cycle?
a: G1 to S to G2 to mitosis to cytokinesis
b: G1 to G2 to S to mitosis to cytokinesis
c: G1 to G2 to mitosis to S to cytokinesis
d: G1 to S to G2 to cytokinesis to mitosis
a: G1 to S to G2 to mitosis to cytokinesis
DNA consists of two antiparallel strands of nucleotides held together by..?
a: covalent bonds.
b: ionic bonds.
c: peptide bonds.
d: hydrogen bonds
d: hydrogen bonds
in the formation of gametes, when does DNA replicate?
a. between telophase I and prophase II
b. during prophase I
c. immediately before prophase I
d. during S phase
d. during s phase
- separation of _____ occurs in anaphase II of meiosis.
- separation of _____ occurs in anaphase I of meiosis.
a. homologous chromosomes
b. sister chromatids
- sister chromatids
- homologous chromosomes
daughter cells produced in meiosis have ____.
a. one-fourth the number of chromosomes as daughter cells produced in mitosis
b. the same number of chromosomes as daughter cells produced in mitosis
c. half the number of chromosomes as daughter cells produced in mitosis
d. twice the number of chromosomes as daughter cells produced in mitosis
c. half the number of chromosomes as daughter cells produced in mitosis
a trait is most likely to exhibit continuous variation if it is controlled by
a. many gene loci, each with a single possible allele.
b. two gene loci with epistasis.
c. a single gene locus with two codominant alleles.
d. many gene loci, each with several possible alleles.
d. many gene loci, each with several possible alleles.
According to Mendel’s Principle of Segregation
a. each individual has two separate alleles controlling each trait.
b. each allele pair separates independently of all other allele pairs.
c. heterozygous individuals have one dominant allele and one recessive allele.
d. the two alleles at each gene locus separate during gamete formation.
b.
The physical basis for the independent assortment of alleles when gametes are formed is
a. the independent alignment of sister chromatids during metaphase I.
b. the independent replication of chromosomes during interphase.
c. the independent alignment of homologous pairs during metaphase I.
d. the random combination of gametes during fertilization.
c. the independent alignment of homologous pairs during metaphase I.
Morgan studied the genetics of fruit flies. One reason fruit flies are a good model organism in the study human genetics is the fruit fly genome has XX chromosomes for females and XY chromosomes for males. The normal eye color for fruit flies is red. When two red-eyed F1 generation flies mated with each other, the F2 generation of this cross included both red- and white-eyed flies. An interesting result occurred: all the white-eyed flies were male. What was Morgan’s conclusion to explain this result?
a. The gene involved is located on an autosome, but only in males
b. The gene involved is located on the X chromosome
c. Other male-specific factors influence eye color in flies
d. The gene involved is located on the Y chromosome
b. The gene involved is located on the X chromosome
- The daughter cells produced in meiosis have genetically ____ daughter cells
- The daughter cells produced in mitosis have genetically ____ daughter cells
a. unique
b. identical
- unique
- identical
Independent assortment of chromosomes during meiosis increases the amount of variation in the next generation. What other process during meiosis leads to an increase in variation in the next generation?
a. the formation of 4 haploid daughter cells
b. the two distinct phases, meiosis I and meiosis II
c. the crossing over between homologous chromosomes
d. the attachment of the spindle fibers to homologous chromosomes
c. the crossing over between homologous chromosomes
Both parents have normal pigmentation and were surprised when their child was born without melanin pigmentation, a genetic disorder known as albinism. What can be said about the child’s parents?
a. Both parents must be heterozygous
b. One parent must be homozygous for the recessive allele; the other parent can be homozygous dominant, homozygous recessive, or heterozygous
c. One parent must be homozygous dominant; the other parent must be heterozygous
d. One parent must be heterozygous; the other parent can be homozygous dominant, homozygous recessive, or heterozygous
a. Both parents must be heterozygous
As a genetic counselor, you are constructing a human pedigree for a particular disease. You note that every generation shows the trait, suggesting that the trait is _______.
a. dominant
b. sex-linked
c. polygenic
d. pleiotropic
a. dominant
A crossover in meiosis is an exchange of genetic material between _____.
a. non-sister chromatids of non-homologous chromosomes
b. sister chromatids of homologous chromosomes
c. non-sister chromatids of homologous chromosomes
d. non-sister chromatids of non-homologous chromosomes
c. non-sister chromatids of homologous chromosomes
