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You are working on a team that is designing a new drug. For this drug to work, it must
enter the cytoplasm of specific target cells. Which of the following would be a factor
that determines whether the molecule selectively enters the target cells?
A) hydrophobicity of the drug molecule
B) lack of charge on the drug molecule
C) similarity of the drug molecule to other molecules transported by the target cells
D) lipid composition of the target cells' plasma membrane
Which of the pairs of molecular structures shown below do NOT depict enantiomers
(enantiomeric forms) of the same molecule?
A)
B)
C)
D)
Which of the following is true of carbon?
A) It forms only polar molecules.
B) It can form a maximum of three covalent bonds with other elements.
C) It is highly electronegative.
D) It can form both polar and nonpolar bonds.
Cytosine makes up 42% of the nucleotides in a sample of DNA from an organism.
Approximately what percentage of the nucleotides in this sample will be thymine?
A) 8%
B) 16%
C) 42%
D) 58%
A biologist discovers an alga that is marine, multicellular, and lives at a depth reached
only by blue light. This alga is most likely a type of _____.
A) red algae
B) brown algae
C) green algae
D) golden algae
Which of the following structures or regions is correctly paired with its function?
A) limbic system motor control of speech
B) medulla oblongata emotional memory
C) cerebellum homeostatic control
D) corpus callosum communication between the left and right cerebral cortices
Organisms share many conserved core processes and features, including transcription
and translation using a uniform genetic code. Scientists have used these shared
processes and features in biotechnology. For example, for the process of some
transformations, a plasmid is constructed when a eukaryotic gene of interest is added
with an antibiotic resistant gene such beta-lactamase, which is used for ampicillin
resistance. This plasmid is then inserted into a prokaryotic bacterial cell, such as E-coli,
through a transformation process that leads to the production of the product protein
from the eukaryotic organism. To culture the bacteria and obtain the protein product, the
bacteria must grow.
Select the appropriate condition to determine if the plasmid has entered the E-coli
bacterial cell.
A) Nutrient broth to which no antibiotic has been added.
B) Water to which ampicillin has been added.
C) Nutrient broth to which ampicillin has been added.
D) Nutrient broth to which other resistant bacteria have been added.
For most terrestrial ecosystems, pyramids composed of species abundances, biomass,
and energy are similar in that they have a broad base and a narrow top. The primary
reason for this pattern is that _____.
A) secondary consumers and top carnivores require less energy than producers
B) at each step, energy is lost from the system
C) biomagnification of toxic materials limits the secondary consumers and top
carnivores
D) top carnivores and secondary consumers have a more general diet than primary
producers
Learning has the most influence on behavior when _____.
A) making mistakes does not result in death
B) animals reproduce asexually
C) animals have enormous cognitive ability
D) making mistakes result in death
The most recently discovered phylum in the animal kingdom (1995) is the phylum
Cycliophora. It includes three species of tiny organisms that live in large numbers on
the outsides of the mouthparts and appendages of lobsters. The feeding stage
permanently attaches to the lobster via an adhesive disk and collects scraps of food
from its host's feeding by capturing the scraps in a current created by a ring of cilia. The
body is sac-like and has a U-shaped intestine that brings the anus close to the mouth.
Cycliophorans are coelomates, do not molt (though their host does), and their embryos
undergo spiral cleavage.
Basing your inferences on information in the paragraph above, to which clade(s) should
cycliophorans belong?
1. Eumetazoa
2. Deuterostomia
3. Bilateria
4. Ecdysozoa
5. Lophotrochozoa
A) 1 and 3
B) 1, 3, and 5
C) 2, 3, and 4
D) 2, 3, and 5
After blood flow is artificially reduced at one kidney, you would expect that kidney to
secrete more of the hormone known as _____.
A) angiotensinogen
B) renin
C) antidiuretic hormone
D) atrial natriuretic peptide
Which of the following is (are) unique to animals?
A) the structural carbohydrate, chitin
B) nervous system signal conduction and muscular movement
C) heterotrophy
D) flagellated gametes
Which of the following will increase the speed of an action potential moving down an
axon?
I) Action potentials move faster in larger diameter axons.
II) Action potentials move faster in axons lacking potassium ion channels.
III) Action potentials move faster in myelinated axons.
A) only I and II
B) only II and III
C) only I and III
D) I, II, and III
A new organism is discovered in the forests of Costa Rica. Scientists there determine
that the polypeptide sequence of hemoglobin from the new organism has 72 amino acid
differences from humans, 65 differences from a gibbon, 49 differences from a rat, and 5
differences from a frog. These data suggest that the new organism is more closely
related to _____.
A) humans than to frogs
B) frogs than to humans
C) rats than to frogs
D) gibbons than to rats
Clonal selection and differentiation of B cells activated by antigen exposure leads to the
production of _____.
A) large quantities of the antigen initially recognized
B) vast numbers of B cells with random antigen-recognition receptors
C) long-lived erythrocytes that can later secrete antibodies for the antigen
D) short-lived plasma cells that secrete antibodies for the antigen
The color of throats of males in a population of side-blotched lizards is determined by
_____.
A) ambient temperature: blue = cold; orange = normal; yellow = hot
B) stage of development/maturity
C) their receptiveness to mate
D) the success of the mating behavior of each of the throat color phenotypes
The process of obtaining food is known as _____ and requires specialized mouthparts.
A) ingestion
B) digestion
C) absorption
D) excretion
Researchers found E. coli that had mutation rates one hundred times higher than
normal. Which of the following is the most likely cause of these results?
A) The single-stranded binding proteins were malfunctioning.
B) There were one or more mismatches in the RNA primer.
C) The proofreading mechanism of DNA polymerase was not working properly.
D) The DNA polymerase was unable to add bases to the end of the growing nucleic
acid chain.
The transfer of fluid from the glomerulus to Bowman's capsule _____.
A) results from active transport
B) transfers large molecules as easily as small ones
C) is very selective as to which subprotein-sized molecules are transferred
D) is mainly a consequence of blood pressure in the capillaries of the glomerulus
Which of the following pairs of proteins shares the most overall similarity in structure?
A) B-cell receptors and T-cell receptors
B) B-cell receptors and antibodies
C) T-cell receptors and antibodies
D) antibodies and antigens
The following figure depicts the outline of a large fairy ring that has appeared overnight
in an open meadow, as viewed from above. The fairy ring represents the furthest
advance of this mycelium through the soil. Locations A-D are all 0.5 meters below the
soil surface.
At which location is the mycelium currently absorbing the most nutrients per unit
surface area, per unit time?
A) A
B) B
C) C
D) D
Mutations that occur in one member of a gene pair that arose from gene duplication
may create _____.
A) a pseudogene
B) a gene with a new function
C) a gene family with two distinct but related members
D) a pseudogene, a gene with a new function, and a gene family with two distinct but
related members
A new DNA strand elongates only in the to direction because _____.
A) DNA polymerase begins adding nucleotides at the end of the template
B) the polarity of the DNA molecule prevents addition of nucleotides at the end
C) replication must progress toward the replication fork
D) DNA polymerase can add nucleotides only to the free end
Which chemical group can act as an acid?
A) amino
B) carbonyl
C) carboxyl
D) methyl
Which factor is most important for explaining why there are equal numbers of snapping
shrimp species on either side of the isthmus?
A) the relative shortness of time they have been separated
B) the depth of the ocean
C) the number of actual depth habitats between the surface and the sea floor
D) the elevation of the isthmus above sea level
What role do chloride cells play in osmoregulation of marine fish with bony skeletons?
A) They actively transport chloride into the gills.
B) They mediate the movement of salt from seawater through their gills.
C) They are involved in excretion of excess salt.
D) They actively transport salt across the basolateral membrane of the rectal gland.
A plant developed a mineral deficiency after being treated with a fungicide. What is the
most probable cause of the deficiency?
A) Mineral receptor proteins in the plant membrane were not functioning.
B) Mycorrhizal fungi were killed.
C) Active transport of minerals was inhibited.
D) Proton pumps reversed the membrane potential.
When imbalances occur in the sex ratio of sexual species that have two sexes (that is,
other than a 50:50 ratio), the members of the minority sex often receive a greater
proportion of care and resources from parents than do the offspring of the majority sex.
This is most clearly an example of _____.
A) sexual selection
B) balancing selection
C) stabilizing selection
D) frequency-dependent selection
An embryo with meroblastic cleavage, extraembryonic membranes, and a primitive
streak must be that of _____.
A) an insect
B) an amphibian
C) a bird
D) a sea urchin
In the diagram below, "A" is _____ ; "B" is _____.
A) the most recent species to evolve on Earth; an ancestor of group "A"
B) the most recent species to evolve on Earth; the last common ancestor of Archaea and
Eukarya
C) the common ancestor of all life; the common ancestor of Bacteria and Archaea
D) the common ancestor of all life; the last common ancestor of Archaea and Eukarya
Somatic cells of roundworms have four individual chromosomes per cell. How many
chromosomes would you expect to find in an ovum from a roundworm?
A) four
B) two
C) eight
D) a diploid number
As cytokinins are primarily produced in roots, what route would they travel to influence
lateral shoot formation in a recently topped tree?
A) symplastic
B) trachieds/vessels
C) phloem
D) apoplastic
One hypothesis that has been proposed regarding the origin of life suggests that life
evolved from an "RNA world" to today's "DNA world." Considering the properties of
RNA and DNA molecules, which questions would direct an investigation of the most
insightful test(s) of this hypothesis?
A) Is it likely that RNA molecules functioned as ribozymes to synthesize DNA from
amino acids, and that this role was reversed when DNA became the information source?
B) Is it likely that simple, yet stable RNA molecules served as a primitive precursor to a
less stable DNA molecule that was more capable of storing more information?
C) Could RNA have provided a template for DNA assembly, thereby enabling a more
stable molecule that is replicated more accurately?
D) Since ribozymes could freely enter and leave the vesicles, could these molecules
have brought external DNA into the cell as a less stable, but more reliable storage
molecule of double-stranded DNA?
