Which of the following statements regarding plasmodesmata is false?
A) Plasmodesmata penetrate plant cell walls.
B) Plasmodesmata carry chemical messages between plant cells.
C) Plasmodesmata carry nutrients between plant cells.
D) Plasmodesmata are found in plants as well as some single-celled organisms.
What is the correct order of structures in a chromosome from smallest to largest?
A) nucleotide, nucleosome, histone, supercoil, tight helical fiber, chromosome
B) nucleosome, nucleotide, histone, tight helical fiber, supercoil, chromosome
C) nucleotide, histone, tight helical fiber, nucleosome, chromosome, supercoil
D) nucleotide, histone, nucleosome, tight helical fiber, supercoil, chromosome
Two yeast cells, one of type a and the other type α, are in proximity to each other. The a
yeast cell has a mutation in the gene for the α factor receptor protein such that the
receptor does not translocate to the surface of the a cell. If both cells secrete their
respective a and α factors, which of the following outcomes is most likely to occur?
A) The a and α cells will grow toward each other.
B) The a cell will grow towards the α cell.
C) The α cell will grow toward the a cell.
D) The a and α cells will not grow toward each other at all.
Which of the following statements regarding hypotheses about inheritance is false?
A) The theory of pangenesis incorrectly suggests that reproductive cells receive
particles from somatic cells.
B) Contrary to the theory of pangenesis, somatic cells do not influence eggs or sperm.
C) The blending hypothesis does not explain how traits that disappear in one generation
can reappear in later generations.
D) The blending hypothesis suggests that all of the traits of the offspring come from
either the mother or the father.
Some populations, especially those with high genetic variability and short life spans,
may avoid extinction as the climate changes through
A) enforcement of the Endangered Species Act.
B) bioprospecting.
C) distribution of populations.
D) evolutionary adaptation.
Which of the following types of reproductive barriers separates two flowering plant
species that could interbreed but for the fact that one has a deep flower tube and is
pollinated by bumblebees whereas the other has a short, narrow flower tube and is
pollinated by honeybees?
A) habitat isolation
B) behavioral isolation
C) mechanical isolation
D) gametic isolation
Studies of the endomembrane system often involve the use of a protein that can emit a
green fluorescence (glow). A researcher wants to make a video of cell behavior, so she
initially tags the outer nuclear envelope of a cell with the fluorescent tag and records for
several hours. Later, she sees that the tag is part of a secretory vesicle.
The ability to stain protein molecules with a fluorescent dye would most clearly allow
researchers to go beyond what they could previously detect with a microscope by
allowing them to
A) detect ribosome activity.
B) detect when DNA is replicating.
C) distinguish a prokaryote from a eukaryote.
D) determine whether a cell had cilia or flagella.
Sex-linked conditions are more common in men than in women because
A) men acquire two copies of the defective gene during fertilization.
B) men need to inherit only one copy of the recessive allele for the condition to be fully
expressed.
C) the sex chromosomes are more active in men than in women.
D) the genes associated with the sex-linked conditions are linked to the Y chromosome,
which determines maleness.
If you found a fossilized dinosaur bone, what could be done to determine the age of the
fossil?
A) Extract and sequence DNA from the bone.
B) Look at pieces of the bone under a microscope.
C) Analyze the isotopes of carbon in the fossil.
D) Compare the appearance of the bone to other fossilized bones.
Cigarette smoking and secondhand smoke cause cancer due to the
A) effects they have on our breathing mechanisms.
B) chemical compounds in the smoke.
C) fact that the chemical compounds are resistant to human immune systems.
D) immunosuppressive effects they display.
Digestion begins in the
A) small intestine.
B) oral cavity.
C) esophagus.
D) stomach.
Which of the following statements about coniferous forests is true?
A) Coniferous forests are the smallest terrestrial biome.
B) Coniferous forests are characterized by long but mild winters and short, dry
summers that are sometimes warm.
C) Coniferous forests usually have nutrient-rich soils.
D) Coniferous forests may experience considerable precipitation, usually in the form of
snow.
One of the evolutionary advantages of having two eyes is that
A) two lenses provide greater magnification.
B) overlapping fields of view provide uninterrupted images.
C) there are more sensory neurons for greater action potentials.
D) the blind spot is eliminated.
Habitats with many edges
A) are the result of natural disasters.
B) favor animals that prefer large, open ranges.
C) often result from human activities.
D) result in a significant increase in diversity.
Which of the following options correctly pairs a polymer and its monomer?
A) cellulose, amino acids
B) DNA, nucleotides
C) collagen, nucleic acids
D) RNA, ribose
The similarities in function of hummingbird wings and the wings of a butterfly reflect
A) homology but not analogy.
B) homology through convergent evolution.
C) analogy and homology.
D) analogy but not homology.
Crossing over ________ genes into assortments of ________ not found in the parents.
A) recombines unlinked; genes
B) recombines linked; alleles
C) combines unlinked; alleles
D) combines linked; genes
Your throat is dry, and you want the last cough drop in the box to last a long time in
your mouth. What should you do?
A) Break the cough drop into little pieces and put them all in your mouth. Since each
little piece must be dissolved separately, the drop will last longer.
B) Keep the cough drop whole. This maintains the largest surface-to-volume ratio and
slows the dissolution of the cough drop.
C) Break the cough drop into little pieces and put them all in your mouth. This
decreases the surface-to-volume ratio and slows the dissolution of the cough drop.
D) It doesn’t matter if the cough drop is in one piece or many pieces; the total amount of
cough drop is all that matters.
Urine flows from the collecting duct into the
A) ureter.
B) urethra.
C) renal pelvis.
D) distal tubule.
Suppose you conduct the study and obtain the results graphed above. What can you
conclude about the correlation between anti-HPV antibody levels and incidence of
HPV-related cancers?
A) As antibody levels increase, the incidence of HPV-related cancers consistently
increases.
B) As antibody levels increase, the incidence of HPV-related cancers consistently
decreases.
C) An antibody levels increase, the incidence of HPV-related cancers consistently stays
the same.
D) There is no consistent correlation between anti-HPV antibody levels and the
incidence of HPV-related cancers.
Studies of the endomembrane system often involve the use of a protein that can emit a
green fluorescence (glow). A researcher wants to make a video of cell behavior, so she
initially tags the outer nuclear envelope of a cell with the fluorescent tag and records for
several hours. Later, she sees that the tag is part of a secretory vesicle.
What likely happened during the intervening time?
A) The outer membrane of the nucleus broke off and moved the fluorescent tag to the
Golgi.
B) The endoplasmic reticulum engulfed the tagged protein and released it in a secretory
vacuole.
C) Material from the nucleus, including the tag, was being secreted outside the cell.
D) The tag was seen in the Golgi before being seen in a secretory vacuole.
The fluid mosaic model describes the plasma membrane as consisting of
A) a phospholipid bilayer with embedded carbohydrates.
B) two layers of phospholipids with cholesterol sandwiched between them.
C) carbohydrates and phospholipids that can drift in the membrane.
D) diverse proteins embedded in a phospholipid bilayer.
Studies of the endomembrane system often involve the use of a protein that can emit a
green fluorescence (glow). A researcher wants to make a video of cell behavior, so she
initially tags the outer nuclear envelope of a cell with the fluorescent tag and records for
several hours. Later, she sees that the tag is part of a secretory vesicle.
The fluorescent tag likely did not become incorporated into which of the following
organelles?
A) lysosome
B) Golgi
C) microtubules
D) rough ER
Protein synthesis requires the use of mRNA, which
A) is made in the nucleolus.
B) must be made by the ribosomes.
C) is translated by the ribosomes into the amino acid sequences of proteins.
D) carries the message to the nucleus to synthesize new DNA during cell division.
Complete metamorphosis is considered to occur in a species
A) if the larva and adult have different diets.
B) if the larva and adult live in different habitats.
C) if a pupation stage separates the larval and adult stages.
D) if the adult has wings, but the larva does not.
A single steroid hormone can cause different effects in different cells by
A) binding to different receptors.
B) acting on different organelles.
C) activating different second messengers.
D) activating different enzymes.
Scientists worry that global warming will result in the oceans
A) becoming more acidic.
B) becoming more basic.
C) containing less dissolved oxygen.
D) containing less dissolved carbon dioxide.
Why was drip irrigation developed?
A) Drip irrigation uses less water than traditional methods.
B) Drip irrigation increases soil erosion.
C) Drip irrigation increases soil salinity.
D) Drip irrigation increases evaporation and drainage.
After reading the paragraphs below, answer the questions that follow.
In 2004, scientists announced the discovery of the fossil remains of some extremely
short early humans on the Indonesian island of Flores. The new species has been named
Homo floresiensis. One hypothesis is that H. floresiensis evolved from Homo erectus,
another early human species. How did a population of H. erectus become isolated on
this remote island? Early humans constructed boats and rafts, so perhaps they were
blown far off course by strong winds during a storm.
H. erectus averaged almost 6 feet in height, but the remains show that adults of H.
floresiensis were only about 3 feet tall. It is hypothesized that limited resources on this
hot and humid island (only 31 square miles) exerted selection pressure, and succeeding
generations began to shrink in size. Small bodies require less food, use less energy, and
are easier to cool than larger bodies. Evolution of small size in similar circumstances
has been observed in many other species, but never before in humans. This find
demonstrates that evolutionary forces operate on humans in the same way as on all
other organisms.
If H. floresiensis were reunited with H. erectus at a much later date, but the two
populations could no longer interbreed, it would be correct to conclude that
A) H. floresiensis is no longer fertile as a species.
B) the two groups had been isolated for more than 50,000 years.
C) H. floresiensis has become less fit than H. erectus.
D) a reproductive barrier had evolved.
One difference between gram-positive and gram-negative bacteria is that
A) gram-positive bacteria have more peptidoglycan in their cell walls.
B) gram-positive bacteria have fimbriae but gram-negative bacteria do not.
C) gram-positive bacteria are spiral-shaped, and gram-negative bacteria are either
rod-shaped or spherical.
D) only gram-negative bacteria can form endospores.
Which of the following options incorrectly pairs a class of sensory receptor with one of
the stimuli it detects?
A) electromagnetic receptorslight
B) chemoreceptorsmolecular structure
C) mechanoreceptorssound
D) thermoreceptorstouch
The creation of genetically identical offspring by a single parent, without the
participation of sperm and egg, is called
A) asexual reproduction.
B) sexual reproduction.
C) regeneration.
D) spontaneous generation.