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Which of the following factors contributes to the flow of blood in veins?
A) skeletal muscle contractions
B) the number of red blood cells in venous blood
C) the diameter of capillaries
D) blood pressure generated by the heart
Signal transduction pathways
A) are found strictly in multicellular organisms which require cell-to-cell
communication.
B) are limited for use in sexual identification.
C) originally evolved in vertebrates.
D) are mechanisms of communication that probably evolved in ancient prokaryotes.
Which of the following statements concerning biological clocks is false?
A) Innate circadian rhythms generally differ slightly from a 24-hour period.
B) Circadian rhythms occur with or without external stimuli.
C) Biological clocks are strongly influenced by external temperatures.
D) Movement of plants long distances very quickly induces a kind of plant "jet lag."
You and your lab partner are observing a cell under a microscope, but you do not know
whether it is a eukaryote or a prokaryote. Which of the following observations
regarding the chromosomes would you use to immediately conclude that the cell is a
eukaryote?
A) The chromosomes are circular in structure.
B) The chromosomes are housed in a membrane-enclosed nucleus.
C) The chromosomes contain very few proteins.
D) The chromosomes are very simple in structure.
Which of the following animals requires the largest and most complex lungs
proportional to its overall body size?
A) frog
B) turtle
C) bear
D) newt
Which of the following statements regarding Down syndrome is false?
A) Trisomy 21 is the cause of Down syndrome.
B) Down syndrome is the most common serious birth defect in the United States.
C) People with Down syndrome usually have a shorter life span than normal.
D) Down syndrome is least likely to be seen in the infants of mothers over 40.
Which of the following has the greatest impact on the global water cycle?
A) removing animals from their biome
B) human destruction of forests
C) connecting aquatic and terrestrial biomes
D) human overuse of water resources for large cities
Which of the following statements about human demographic trends is true?
A) As women's status and education increase, they choose to have more children.
B) After 1950, mortality rates increased rapidly in most developing countries.
C) A human population in which women reproduce at a later age will experience slower
population growth.
D) The movement from high birth rates and low death rates to low birth rates and high
death rates is called the demographic transition.
A scientist wants to examine living cells lining the respiratory tract to determine how
the cells use tiny hairs to move dirt and mucus away from the lungs. Which of the
following instruments would be best, and why?
A) a light microscope, because it allows observations of whole, live cells
B) a transmission electron microscope, because it has high resolution
C) a scanning electron microscope, because it can reveal structures on cell surfaces
D) a scanning electron microscope, because it can be used to observe whole cells
without slicing them
DNA ligase binds
A) recombinant DNA to transformed bacterial cells.
B) recombinant DNA to recombinant proteins.
C) nucleotides in the DNA backbone together.
D) nucleotide base pairs together.
You take a 1-mL sample of pond water and add it to a colorless, viscous media in a
small petri dish. When you place it under your dissecting microscope, you see three
organisms. Two are struggling to move efficiently through the media, while the third
moves more quickly. You attribute the faster movement to the third organism's
A) thick cell wall.
B) flagella.
C) fimbriae.
D) chloroplasts.
A population of butterflies has an allele B for big spots on the wings and b for small
spots on the wings. The table below provides data about this population.
Regarding these data about the butterfly population, which of the following statements
is correct?
A) The population is in Hardy-Weinberg equilibrium because the number of B alleles is
equal to the number of b alleles.
B) The population is in Hardy-Weinberg equilibrium because half of the heterozygotes
are B and half are b.
C) The population is not in Hardy-Weinberg equilibrium because p2 and 2pq are
different.
D) The population is not in Hardy-Weinberg equilibrium because the genotype
frequency of bb is greater than it would be in equilibrium.
A group of dog breeders is trying to design and develop an ideal dog. They want a dog
with a gentle disposition, black fur, long ears, short legs, and a strong sense of smell.
Which of the following comments from fellow dog breeders represents the biggest
challenge they are likely to face?
A) There are breeds with long ears and breeds with short leg, but no breeds with both.
B) There does not seem to be any genetic variation in sense of smell.
C) Artificial selection is artificial and cannot change the genetics of a breed like natural
selection.
D) Most dogs with black fur have long legs.
What is the difference between the heartwood and sapwood of a tree?
A) Heartwood contains xylem, and sapwood contains phloem.
B) Sapwood contains xylem, and heartwood contains phloem.
C) Heartwood no longer transports water and minerals, and sapwood still conducts
xylem sap.
D) Heartwood contains old phloem that no longer functions, and sapwood contains
functioning phloem.
Over the past 400 years, humans have documented the extinction of more than
________ species. This modern rate of species extinction is estimated to be ________
the normal extinction rate seen in the fossil record.
A) 100; about the same as
B) 400; about double
C) 1,000; over 100 times greater than
D) 10,000; at least 1 million times greater than
If you were working for a pharmaceutical company as part of a drug discovery team,
which of these enzyme inhibitors would you suggest as a productive avenue for drug
development?
A) a drug to treat high blood pressure that reversibly inhibits an enzyme catalyzing
production of a chemical that causes blood vessels to contract
B) a drug to treat diabetes that irreversibly inhibits an enzyme in the metabolic pathway
to synthesize glucose
C) a compound that acts as a competitive inhibitor for a digestive enzyme produced
only in the presence of certain foods
D) a compound that inhibits enzymes by significantly changing the pH throughout the
body
Ventricular contraction normally begins at the apex (bottom of the heart). What would
likely happen if ventricular contraction originated at the intersection of the atria and the
ventricles instead?
A) Blood would be pumped through the semilunar valves.
B) Blood would be pumped through the AV valves.
C) Blood would be pumped back into the atria.
D) Blood would be pumped down to the apex of the heart.
Which of the following statements about ribosomes is false?
A) A ribosome consists of two subunits.
B) Ribosomal subunits are made of proteins and ribosomal RNA.
C) The ribosomes of prokaryotes and eukaryotes are the exactly the same in structure
and function.
D) Each ribosome has two binding sites for tRNA molecules.
In most green plants, chloroplasts are
A) concentrated in a zone of leaf tissue called the mesophyll.
B) concentrated in a portion of the leaf called the stroma.
C) evenly distributed throughout the leaf tissue.
D) evenly distributed throughout the entire plant.
A physician is trying to determine if a patient has functioning helper T cells. Which of
the following events would provide evidence that helper T cells are acting normally?
A) Antibodies recognize and bind to antigens.
B) Memory cells are produced after the secondary immune response.
C) Stimulatory proteins are secreted that help activate B cells, thus stimulating the
humoral immune response.
D) The inflammatory response is triggered.
If you were to add olive oil to your food as part of a diet to lower your risk of
atherosclerotic disease, you would use olive oil that
A) is liquid at room temperature.
B) is hydrogenated.
C) is modified to be solid at room temperature.
D) has lard added to it.
Natural selection tends to correlate the structures of a nervous system with an animal's
interaction with the environment. A good example is sessile or slow-moving molluscs
such as clams, which
A) have little or no cephalization and simple sense organs.
B) use chemical synapses to process complex information.
C) have a well-developed brain that functions as a master control center.
D) use their circulatory system as a mechanism for distributing nerve impulses.
Considering only the steps that take place during translation, which of the following is
not needed in order for translation to occur?
A) DNA template
B) ribosomes
C) tRNA
D) sources of energy, including ATP
Individuals medically diagnosed with "dry eyes" experience feelings of dryness,
itchiness, burning, and general irritation in their eyes. Dry eyes can be caused by a
decreased production of tears by the tear-producing glands in the eyes. Which of the
following would help alleviate dry eyes?
A) Stimulate production of aqueous humor.
B) Block the eyelid openings used to drain tears so that the limited amount of tears
produced can stay longer on the eyes' surface.
C) Stimulate production of vitreous humor.
D) Avoid environments with dry climates (little moisture).
The two diseases that represent high-priority threats as biological weapons today are
A) smallpox and typhus.
B) syphilis and HIV.
C) anthrax and botulinum toxin.
D) anthrax and Thiobacillus.
The transfer of genetic information from DNA to RNA is called
A) translation.
B) transcription.
C) initiation.
D) elongation.
The cholesterol associated with animal cell membranes
A) is attached to membrane proteins and extends into the watery environment
surrounding the cell.
B) helps to keep phospholipids from being too close to one another.
C) is an abnormality resulting from a diet high in cholesterol.
D) helps solidify the membranes when the room temperature is below freezing.
A protein containing more than one polypeptide chain exhibits the ________ level of
protein structure.
A) primary
B) secondary
C) tertiary
D) quaternary
The results of dehydration synthesis can be reversed by
A) condensation.
B) hydrolysis.
C) polymerization.
D) the addition of an amino group.
An organ system consists of
A) organs that collectively perform a vital body function.
B) a group of coordinated tissues.
C) a collection of similar cells.
D) blood, lymph, and other body fluids.
Your first big biology exam is coming up in a few days, and in order to prepare for
late-night study sessions, you buy a box of Yummies, a delicious type of snack cake.
After checking out the nutrition facts label on the side of the box, you discover that a
single Yummie cake contains 4.5 grams of total fat, 27 grams of carbohydrate, 0 grams
of fiber, and 1 gram of protein.
After eating a Yummie cake, which of the following metabolic processes is likely
occurring at the fastest rate?
A) hydrolysis of glycogen
B) dehydration reactions involving glucose
C) dehydration reactions involving fatty acids
D) hydrolysis of cellulose
