Biology 100 Practice Challenge Examination
The Biology 100 Practice Challenge Examination contains 100 multiple choice questions. CHOOSE THE BEST RESPONSE FOR EACH QUESTION. A score of 70 percent on the practice examination might indicate that a student could successfully complete the Biology 100 Challenge Examination with the minimal proficiency of 70 percent or better.

 

1.
Life is organized in a hierarchical fashion. Which of the following sequences correctly illustrates that hierarchy as it goes upward?
A.
ecosystem, population, organ system, cell, community, molecule, organ, organism
B.
organism, organ system, population, organ, community, cell, ecosystem, molecule
C.
cell, molecule, organ system, organ, population, organism, ecosystem, community
D.
molecule, cell, organ, organ system, organism, population, community, ecosystem
E.
ecosystem, molecule, cell, organism, organ system, population, organ, community


2.
Science _______________.
A.
is based on faith
B.
builds on what has been learned earlier
C.
is self-correcting
D.
is based on evidence
E.
. all of the above, except A


3.
A scientist examines a group of cells under a light microscope. She notices the presence of nuclei within these cells. Chemical tests reveal that each cell is surrounded by a wall composed of cellulose. She concludes that the cells come from an organism that is a member of the kingdom _______.
A.
Fungi
B.
Animalia
C.
Monera
D.
Protista
E.
Plantae


4.
Which of the following is a property (are properties) of life?
A.
ability to metabolize
B.
a precise structural arrangement
C.
irritability
D.
presence of nucleic acid
E.
A, B, and C


5.
The teeth of grain-eating animals (such as cows) are usually broad and ridged. This makes them suitable for grinding and chewing. Meat-eating animals (such as lions) have pointed teeth that are good for puncturing and ripping flesh. This illustrates ________.
A.
a food web
B.
a result of natural selection
C.
the connection between form and function
D.
both B and C
E.
both A and B


6.
An antibiotic kills 99.9 percent of a bacterial population. One would expect the next generation of bacteria _____.
A.
to be more resistant to that antibiotic
B.
to be more contagious than the prior generation
C.
to die out due to the drastic decrease in population size
D.
to be just as susceptible to that antibiotic as was the previous generation
E.
all of the above


7.
An uncharged atom of gold has an atomic number of 79 and an atomic mass of 197. This atom has _____ protons, ______ neutrons, and ______ electrons.
A.
79, 118, 79
B.
118, 79, 118
C.
276, 118, 79
D.
118, 276, 118
E.
79, 276, 79


8.
The hydrogen atoms of a water molecule are bonded to the oxygen atoms by _______ bonds, whereas neighboring water molecules are held together by _______ bonds.
A.
polar covalent; hydrogen
B.
hydrogen; polar covalent
C.
hydrogen; ionic
D.
polar covalent; ionic
E.
ionic; covalent


9.
Which of the following is an example of secondary structure in a protein?
A.
a particular amino acid sequence
B.
an alpha helix
C.
a globular shape
D.
a pleated sheet
E.
both B and D


10.
Suppose a cell grows to twice its original volume. What must happen to the ratio of the cell's surface area to its volume? Why?
A.
The ratio must decrease if the cell is to continue obtaining enough nutrients and gases.
B.
The ratio must stay the same, so that the balance of the transport of materials into and out of the cell will not
        be disturbed.
C.
The ratio must decrease, or the cell will lose too many biomolecules through its membrane.
D.
The ratio must increase if the cell is to continue obtaining enough nutrients and gases.
E.
both A and B


11.
Chronic administration of a drug (such as a barbiturate or an antibiotic) may cause the liver to _____.
A.
increase production of enzymes that detoxify the drug in question
B.
increase the body's tolerance to the drug
C.
produce additional smooth endoplasmic reticulum
D.
produce and transport more bile to the gall bladder
E.
A, B, and C


12.
When a cell is deprived of oxygen, its lysosomes tend to burst and release their contents into the cell. As a result of this, that cell will______________.
A.
undergo autolysis (self-digestion)
B.
recycle damaged organelles
C.
undergo cell division
D.
produce additional ER
E.
produce replacement lysosomes


13.
A manufacturing company dumps its wastes into a nearby pond. One of the wastes is found to paralyze the contractile vacuoles of certain protists. A biologist looking at one of these organisms would find that the organism _______.
A.
has lost water and shrunk
B.
is surviving but is unable to reproduce
C.
has died because wastes have accumulated in the cytoplasm
D.
has gained water and burst
E.
has died of malnutrition


14.
ATP can be used as the cell's energy currency because ________.
A.
endergonic reactions can be fueled by coupling them with the formation of ATP from ADP
B.
ATP is the most energy-rich molecule in the cell
C.
endergonic reactions can be fueled by coupling them with the hydrolysis of high-energy phosphate
        bonds in ATP
D.
the regeneration of ATP from ADP can be fueled by coupling it with exergonic reactions
E.
both C and D


15.
A child is brought to the hospital with a fever of 107oF. Doctors immediately order an ice bath to lower the child's temperature. Which explanation offers the most logical reason for this action?
A.
Elevated body temperature will increase the energy of activation needed to start various chemical reactions
        in the body. This will interfere with the ability of enzymes to catalyze vital chemical reactions.
B.
Elevated body temperatures may denature enzymes. This would interfere with the cell's abilities to
        catalyze various reactions.
C.
Elevated body temperatures cause molecules to vibrate more quickly and prevent enzymes from easily
        attaching to reactants. This will slow vital body reactions.
D.
Elevated body temperatures easily break the covalent bonds linking biologically important molecules. This
        will cause a general breakdown of cell structures.
E.
Elevated body temperature will increase reaction rates in the child's cells and overload the limited number
        of enzymes found in the cell.


16.
Bacterial production of the enzymes needed for the synthesis of the amino acid tryptophan declines with increasing levels of tryptophan and increases as tryptophan levels decline. This is an example of ________.
A.
negative feedback
B.
positive feedback
C.
competitive inhibition
D.
irreversible inhibition
E.
noncompetitive inhibition


17.
In lab, one uses a special balloon that is permeable to water but not sucrose to make an “artificial cell.” The balloon is filled with a solution of 20 percent sucrose and is immersed in a beaker containing a solution of 40 percent sucrose. Which of the following will occur?
A.
Sucrose will leave the balloon.
B.
Sucrose will enter the balloon.
C.
Water will enter the balloon.
D.
Water will leave the balloon.
E.
both A and D


18.
Which of the following pieces of evidence would prove that a substance enters a cell by active rather than passive transport?
A.
The substance is moved across the cell membrane by a carrier protein.
B.
The substance enters the cell when its concentration is higher outside the cell than inside.
C.
The breakdown of ATP is needed for the transport to occur.
D.
both A and C
E.
all of the above


19.
A drug is tested in the laboratory and found to create holes in both mitochondrial membranes. Scientists suspect that drug will be harmful to human cells because it will inhibit _________.
A.
the Krebs cycle
B.
chemiosmosis
C.
the formation of alcohol
D.
glycolysis
E.
both A and B


20.
A culture of bacteria growing aerobically is fed glucose containing radioactive carbon and is then examined. AS the bacteria metabolize the glucose, radioactivity will appear first in _______.
A.
carbon dioxide
B.
NADH
C.
ATP
D.
glucose 6-phosphate
E.
pyruvic acid


21.
During chemiosmosis, ________.
A.
energy is generated by coupling exergonic reactions with other exergonic reactions
B.
energy is generated because H+ ions move freely across mitochondrial membranes
C.
a concentration gradient is generated when large numbers of H+ ions are passively transported from
        the matrix of the mitochondrion to the mitochondrion's intermembrane space
D.
ATP is synthesized when H+ ions move through a protein port provided by ATP synthase
E.
both B and C


22.
Prokaryotes do not have mitochondria. This means that _________.
A.
glycolysis cannot occur
B.
the Krebs cycle cannot occur
C.
chemiosmosis cannot occur
D.
all three cycles can occur because bacteria don't need mitochondria for these events
E.
neither the Krebs cycle nor chemiosmosis can occur


23.
When a organism such as a yeast lives by fermentation, it converts the pyruvic acid from glycolysis into a different compound such as alcohol. Why doesn't the yeast secrete the pyruvic acid directly?
A.
The conversion yields one ATP per pyruvic acid molecule.
B.
The conversion yields one NADH per pyruvic acid molecule.
C.
A buildup of pyruvic acid in the surrounding environment would be too toxic.
D.
The conversion is needed to regenerate the NAD+ consumed during glycolysis.
E.
The conversion yields one FADH2 per pyruvic acid molecule.


24.
Yeast can produce ATP by either fermentation or chemiosmosis; thus they are ______.
A.
obligate anaerobes
B.
producers of lactic acid
C.
facultative anaerobes
D.
facultative aerobes
E.
obligate aerobes


25.
Which of the following is true concerning the role of redox reactions in photosynthesis and cellular respiration?
A.
Photosynthesis involves only oxidations; respiration involves only reductions.
B.
In photosynthesis, carbon dioxide is oxidized for form sugar; in respiration, sugar is reduced to form
        carbon dioxide.
C.
Photosynthesis involves only reductions; respiration involves only oxidations.
D.
In photosynthesis, carbon dioxide is reduced to form sugar; in respiration, sugar is oxidized to
        form carbon dioxide.
E.
both A and D are true


26.
Photorespiration is _________.
A.
the light-driven cleavage of glucose to yield three two-carbon compounds, which are broken down to
       CO2 without producing ATP
B.
the incorporation of O2 instead of CO2 by rubisco, yielding a two-carbon compound that is broken down
        to CO2 and H2O
C.
the increase in the rate of mitochondrial respiration that takes place when a leaf is exposed to light and
        photosynthesis produces glucose
D.
the opening and closing of stomata in response to changes in light intensity
E.
ATP synthesis driven by light energy


27.
Which of the following occur during mitotic anaphase?
A.
daughter chromosomes begin to move toward opposite poles of the cell
B.
sister chromatids separate
C.
the chromatin is replicated
D.
the centromeres of each chromosome divide
E.
A, B, and D


28.
Two chromosomes in a nucleus that carry loci for the same traits in the same positions on the chromosomes but may specify different versions of some traits constitute a pair of ________________.
A.
heterozygous chromosomes
B.
complementary chromosomes
C.
homologous chromosomes
D.
polyploid chromosomes
E.
both A and C


29.
During which stage of meiosis does synapsis and the formation of tetrads occur?
A.
interphase I
B.
prophase I
C.
prophase II
D.
interphase II
E.
metaphase II


30.
An allele that has no noticeable effect on the phenotype of an organism unless it is found in a homologous condition is said to be ______.
A.
recessive
B.
dominant
C.
codominant
D.
incompletely dominant
E.
heterozygous


31.
The phenomenon of a single gene producing multiple phenotypes is known as ________.
A.
incomplete dominance                    
    B blending inheritance
B.
pleiotropy
C.
codominance
D.
polygenic inheritance


32.
A “normal” human gamete would contain _____ sex chromosome(s).
A.
none
B.
one
C.
two
D.
three
E.
C or D


33.
How much genetic material is present in a cell during prophase I compared with a cell that has completed meiosis II?
A.
the same amount
B.
one-quarter as much
C.
four times as much
D.
one-half as much
E.
twice as much


34.
An insertion or deletion mutation involving a single nucleotide in the coding sequence of a gene would have what probable effect on the resulting polypeptide, and why?
A.
It might have no effect, or it might result in a polypeptide with a single altered amino acid.
B.
It would prevent synthesis of the polypeptide because it would prevent mRNA from binding properly
        to the gene.
C.
It would have no effect because it is not a significant change.
D.
It would result in a nonfunctional polypeptide because it would alter the reading frame of the
        genetic message.
E.
It would result in the synthesis of a different polypeptide because it would cause RNA polymerase
        to skip the gene and transcribe the next gene downstream.


35.
HIV uses ___________ to synthesize DNA from an RNA template.
A.
terminator enzyme
B.
ligase
C.
reverse transcriptase
D.
RNA polymerase
E.
DNA and RNA helicase


36.
The techniques that are used to join together genes from different sources in a test tube and to insert foreign DNA into an organism's genome are collectively called __________.
A.
recombinant DNA techniques
B.
trans-species recombining
C.
gene cloning techniques
D.
gene application techniques
E.
gene alternation techniques


37.
The process by which a phage transfers bacterial genes from one bacterium to another is called _____.
    A conjugation
A.
recombination
B.
transduction
C.
transposition
D.
transformation


38.
If a fragment breaks off from one chromosome and attaches to another, nonhomologous chromosome, the resulting chromosomal abnormality is called ______.
A.
a deletion
B.
a translocation
C.
an inversion
D.
a nondisjunction
E.
a reciprocal translocation


39.
Which of the following constitutes a basic, modern definition of a species?
A.
a group of individuals who resemble each other, on average, more than they resemble anything else
B.
a group of populations whose individuals have the potential to interbreed and produce viable offspring
C.
a group of individuals who can interbreed
D.
the smallest unit that can engage in microevolution
E.
a group of individuals living in the same place at the same time.


40.
Thirty people are assigned to live in a spaceship that is exploring other galaxies. The journey will take several hundred years and will completed by the descendents of these crew members. The gene pool of the population on this ship when (and if) it returns is most likely to reflect __________.
A.
mutation pressure
B.
gene flow
C.
a bottleneck effect
D.
a founder effect
E.
polymorphism


41.
Plasmodium, the organism that causes malaria, is ______.
A.
an apicomplexan protozoan
B.
a dinoflagellate
C.
a cellular slime mold
D.
an amoeba
E.
a spirochete


42.
One collects a protist off a rotting log and grows it in a Petri dish containing Escherichia coli, which it eats. For a while the protists multiple as single cells. Then the E. coli begins to run short, and the protists aggregate to form a clump, which rises up to become a stalked structure with a globular head. What kind of protist did this individual collect?
A.
an apicomplexan
B.
a dinoflagellate
C.
a cellular slime mold
D.
an actinomycete
E.
a plasmodial slime mold


43.
Plants and green algae share which of the following homologous structures?
A.
cell walls made of cellulose
B.
starch as a storage molecule for carbohydrates
C.
chloroplasts and a specific combination of photosynthetic pigments
D.
all of the above
E.
only A and C


44.
Which of the following correctly describes the alternation of generations in a plant life cycle?
A.
Diploid gametophytes that produce gametes by meiosis alternate with haploid sporophytes that
        produce spores by mitosis.
B.
Diploid gametophytes that produce spores by mitosis alternate with haploid sporophytes that
        produce gametes by meiosis.
C.
Diploid gametophytes that produce gametes by meiosis alternate with diploid sporophytes that
        produce spores by mitosis.
D.
Diploid sporophytes that produce gametes by meiosis alternate with haploid sporophytes that
        produce gametes by mitosis.
E.
Diploid sporophytes that produce spores by meiosis alternate with haploid gametophytes that
        produce gametes by mitosis.


45.
Hypophosphatemia (vitamin D-resistant rickets) is inherited as an X-linked dominant. What is the expected outcome of a cross between a homozygous recessive woman and a man with hypophosphatemia?
A.
All of the sons and none of the daughters exhibit hypophosphatemia.
B.
Seventy-five percent of their offspring exhibit hypophosphatemia.
C.
Fifty percent of their daughters and 50% of their sons exhibit hypophosphatemia.
D.
All of their daughters and none of their sons exhibit hypophosphatemia.
E.
Twenty-five percent of their offspring exhibit hypophosphatemia.


46.
In humans, free earlobes are dominant to attached earlobes, and the presence of freckles is dominant to the absence of freckles. If any individual heterozygous for both traits were to mate with an individual with attached earlobes and no freckles, what is the probability of having a child with attached earlobes and freckles?
A.
0%
B.
25%
C.
100%
D.
50%
E.
75%


47.
An individual with naturally curly hair and an individual with naturally straight hair mate; all of their offspring have naturally wavy hair. If an individual with naturally wavy hair mates with an individual with naturally straight hair, what is probably that their child will have naturally curly hair?
A.
0%
B.
100%
C.
25%
D.
50%
E.
75%


48.
Assume that having three nostrils is inherited as a Y-linked trait. A man with three nostrils has a daughter who has a son by a man who has only two nostrils. What is the probability that the three-nostriled man's grandson has three nostrils?
A.
50%
B.
75%
C.
25%
D.
100%
E.
0%


49.
In humans, the __________________ system provides slow but sustained responses to stimuli by modifying the activities of other organ systems.
A.
lymphatic
B.
endocrine
C.
nervous
D.
cardiovascular
E.
respiratory


50.
Muscle tissue is specialized for ____________.
A.
contraction
B.
secretion
C.
protection
D.
electrical conduction
E.
transport


51.
The initial accumulation of oxygen in the atmosphere was the result of photosynthesis from an organism most like modern _______.
A.
cyanobacteria
B.
algaie
C.
mosses
D.
kelp
E.
eukaryotes


52.
Carbonic acid and sodium bicarbonate act as buffers in the blood. When a small amount of acid is added to this buffer, the H+ ions are used up as they combine with the bicarbonate ions. When this happens, the pH of the blood __________.
A.
becomes basic
B.
becomes acidic
C.
doesn't change
D.
is reversible
E.
ionizes


53.
The compound inositol has six hydroxyl groups attached to a six carbon backbone. Inositol can be classified as a(n) _______.
A.
amine
B.
acid
C.
ketone
D.
alcohol
E.
buffer


54.
The functional group written as –COOH is called the __________ group.
A.
hydroxyl
B.
carbonyl
C.
amino
D.
ketone
E.
carboxyl


55.
The functional group diagramed =O is a(n) _________.
A.
carbonyl
B.
carboxyl
C.
phosphate
D.
amino
E.
hydroxyl


56.
Which of the following has the greatest concentration of hydrogen ions?
A.
household ammonia at pH 11
B.
baking soda at pH (
C.
human blood at pH 7
D.
black coffee at pH 5
E.
cola at pH 3


57.
The portion of a phospholipid that contains the phosphorous group has one or more electric charges. That makes this region of the phospholipid _______.
A.
hydrophobic
B.
hydrophilic
C.
nonpolar
D.
unsaturated
E.
saturated


58.
In a biological membrane, the phospholipids are arranged with the fatty acid chains facing the interior of the membrane. As a result, the interior of the membrane is ________.
A.
hydrophobic
B.
hydrophilic
C.
charged
D.
polar
E.
filled with water


59.
What is the nucleotide sequence of the complementary strand of this DNA molecule: A A T G C G A?
A.
A A T G C G A
B.
G G C A T A G
C.
C C G T T A T
D.
T T A C G C T
E.
A G C G T A A


60.
When a protein loses its three-dimensional structure and becomes nonfunctional, it is ____________.
A.
permanent
B.
reversible
C.
denatured
D.
hydrolyzed
E.
environmentalized


61.
Using a light microscope, it is possible to view cytoplasmic streaming around the central vacuole in cells of the green alga Nitella. Why would one use a light microscope instead of an electron microscope to study this process?
A.
Electron microscopes have less resolving power than light microscopes.