BIOL 58316

What is the function of proton pumps localized in the plant plasma membrane?
A) to transfer phosphorus groups from ATP to proteins
B) to transfer metal ions across the plasma membrane
C) to transfer anions across the plasma membrane
D) to create a membrane potential

If a molecule of carbon dioxide released into the blood in your left toe is exhaled from your nose, it must pass through all of the following EXCEPT _____.
A) the pulmonary vein
B) an alveolus
C) the trachea
D) the right atrium

Which term most precisely describes the cellular process of breaking down large molecules into smaller ones?
A) catabolism (catabolic pathways)
B) metabolism
C) anabolism (anabolic pathways)
D) dehydration

Animals that migrate great distances would obtain the greatest energetic benefit of storing chemical energy as _____.
A) proteins
B) minerals
C) carbohydrates
D) fats

Increasing the temperature of the human scrotum by 2C (that is, near the normal body core temperature) and holding it there would most likely_____.
A) reduce the fertility of the man by impairing the production of gonadal steroid hormones
B) reduce the fertility of the man by impairing spermatogenesis
C) reduce the man’s sexual interest
D) increase the fertility of the affected man by enhancing the rate of steroidogenesis

Use the following information to answer the question(s) below.
A large population of laboratory animals has been allowed to breed randomly for a number of generations. After several generations, 25% of the animals display a recessive trait (aa), the same percentage as at the beginning of the breeding program. The rest of the animals show the dominant phenotype, with heterozygotes indistinguishable from the homozygous dominants.
What is the most reasonable conclusion that can be drawn from the fact that the frequency of the recessive trait (aa) has not changed over time?
A) The two phenotypes are about equally adaptive under laboratory conditions.
B) The genotype AA is lethal.
C) There has been a high rate of mutation of allele A to allele a.
D) There has been sexual selection favoring allele a.

Mature human sperm and ova are similar in that they _____.
A) both have the same number of chromosomes
B) are approximately the same size
C) each have a flagellum that provides motility
D) are produced from puberty until death

Which of the following is a limit of evolution that results in exaptations?
A) Natural selection and sexual selection can work at cross-purposes to each other.
B) Evolution is limited by historical constraints.
C) Adaptations are often compromises.
D) Chance events affect the evolutionary history of populations in environments that can change unpredictably.

Eutrophication is often caused by excess limiting nutrient runoff from agricultural fields into aquatic ecosystems. This results in massive algal blooms, which eventually die and decompose, ultimately depleting the dissolved oxygen and killing large numbers of fish and other aquatic organism. Predict which of the following human actions would best address the problem of eutrophication near agricultural areas?
A) After each eutrophication event, remove the dead fish and invertebrates to place on agricultural fields instead of fertilizer.
B) Determine which limiting nutrient is responsible for the algal bloom and use other fertilizers to apply to crops.
C) Remove the algae before it dies and decomposes to prevent eutrophication from occurring.
D) Determine critical nutrient loads required for certain crops and do not exceed this amount during fertilizer application.

An decrease from pH 7.4 to pH 7.2 causes hemoglobin to _____.
A) release all bound carbon dioxide molecules
B) bind more oxygen molecules
C) increase its binding of H⁺
D) give up more of its oxygen molecules

When an action potential from a motor neuron arrives at the neuromuscular junction (NMJ), a series of events occurs that leads to muscle contraction. Which of the following events will occur last (that is, after all of the others)?
A) acetylcholine (ACh) release
B) conformational change in troponin
C) depolarization of the muscle cell
D) release of Ca²⁺ from the sarcoplasmic reticulum

Increasing the number of stomata per unit surface area of a leaf when atmospheric carbon dioxide levels decline is most analogous to a human _____.
A) breathing faster as atmospheric carbon dioxide levels increase
B) putting more red blood cells into circulation when atmospheric oxygen levels decline
C) removing red blood cells from circulation when atmospheric oxygen levels increase
D) increasing the volume of its lungs when atmospheric carbon dioxide levels increase

Brown-headed cowbirds utilize fragmented forests effectively by _____.
A) feeding on the fruits of shrubs that tend to grow at the forest/open-field interface
B) parasitizing the nests of forest birds and feeding on open-field insects
C) roosting in forest trees and nesting in grassy fields
D) outcompeting other songbird species for access to nesting holes in old-growth trees

Biological evolution of life on Earth, from simple prokaryote-like cells to large, multicellular eukaryotic organisms, _____.
A) has occurred in accordance with the laws of thermodynamics
B) has caused an increase in the entropy of the planet
C) has been made possible by expending Earth’s energy resources
D) has occurred in accordance with the laws of thermodynamics, by expending Earth’s energy resources and causing an increase in the entropy of the planet

Which molecule shown above can form a cross linkage?
A) A
B) B
C) C
D) D

A ball-and-socket joint connects _____.
A) the radius to the ulna
B) the radius to the humerus
C) the ulna to the humerus
D) the humerus to the scapula

Suppose that 100 pollen grains land on a stigma, and 50 mature seeds are formed in the fruit. What does this indicate about the pollination process and success?
A) 50% success: 100 pollen grains grew to 50 ovules, and double fertilization occurred.
B) 50% success: evidently, only 50 sperm pollinated 50 anthers.
C) 50% success: 50 sperm fertilized 50 eggs, and 50 sperm fused with 50 polar nuclei.
D) 50% success: 50 sperm fertilized 50 eggs, and 50 sperm fused with 100 polar nuclei.

In a liver cell detoxifying alcohol and some other poisons, the enzymes of the peroxisome remove hydrogen from these molecules and _____.
A) combine the hydrogen with water molecules to generate hydrogen peroxide
B) use the hydrogen to break down hydrogen peroxide
C) transfer the hydrogen to the mitochondria
D) transfer the hydrogen to oxygen molecules to generate hydrogen peroxide

You observe two female fish of the same species breeding. One female lays 100 eggs and the other female lays 1000 eggs. Which one of the following is LEAST likely given the limits of fitness trade-offs?
A) The female laying 100 eggs breeds more often than the female laying 1000 eggs.
B) The female laying 100 eggs lives longer than the female laying 1000 eggs.
C) The eggs from the female laying 1000 eggs have larger yolks than the yolks of the eggs from the female laying 100 eggs.
D) The female laying 1000 eggs is larger than the female laying 100 eggs.

Insect wings may have begun to evolve as lateral extensions of the body that were used as heat dissipaters for thermoregulation. When they had become sufficiently large, these extensions became useful for gliding through the air. Additional selection refined them as flight-producing wings. If this hypothesis is correct, modern insect wings would be an example of _____.
A) the loss of Hox genes in the evolution of new form
B) mutations
C) an exaptation
D) an adaptive radiation

Which of the following would be the most problematic for the natural environment in the development of genetically engineered crops?
A) the introduction of male sterility into crops
B) the creation of transgenic crops with apomictic seeds
C) the creation of crops with flowers that develop normally, but fail to open
D) the creation of transgenic crops that hybridize more easily

Cooking oil and gasoline (a hydrocarbon) are not amphipathic molecules because they _____.
A) do not have a polar or charged region
B) do not have a nonpolar region
C) have hydrophobic and hydrophilic regions
D) are highly reduced molecules

A person able to hear only high-frequency sounds would probably have which of the following structural problems in the ear?
A) The tympanum is damaged because of chronic ear infections.
B) The basilar membrane is stiffened along its entire length.
C) The ear ossicles are abnormally thickened.
D) All of these problems could result in inability to detect low-frequency sound.

In living systems molecules involved in hydrogen bonding almost always contain either oxygen or nitrogen or both. How do you explain this phenomenon?
A) Oxygen and nitrogen are elements found in both nucleic acids and proteins.
B) Oxygen and nitrogen are elements with very high attractions for their electrons.
C) Oxygen and nitrogen are elements found in fats and carbohydrates.
D) Oxygen and nitrogen were both components of gases that made up the early atmosphere on Earth.

In this eight-year experiment, twelve populations of E. coli, each begun from a single cell, were grown in low-glucose conditions for 20,000 generations. Each culture was introduced to fresh growth medium every twenty-four hours. Occasionally, samples were removed from the populations, and their fitness in low-glucose conditions was tested against that of members sampled from the ancestral (common ancestor) E. coli population.

Compare the bacteria in the figure above in generation 1 and generation 20,000. The bacteria in generation 1 have a greater _____.
A) efficiency at exporting glucose from the cell to the environment
B) ability to survive on simple sugars, other than glucose
C) ability to synthesize glucose from amino acid precursors
D) reliance on glycolytic enzymes

How were conditions on the early Earth of more than three billion years ago different from those on today’s Earth? Unlike Earth today, early Earth _____.
A) had an atmosphere rich in gases released from volcanic eruptions
B) had an oxidizing atmosphere
C) experienced little high energy radiation from the sun
D) had an atmosphere with significant quantities of ozone

Water has many exceptional and useful properties. Which is the rarest property among compounds?
A) Water is a solvent.
B) Solid water is less dense than liquid water.
C) Water has a high heat capacity.
D) Water has surface tension.

Which of the following strategies would most rapidly increase the genetic diversity of a population in an extinction vortex?
A) Capture all remaining individuals in the population for captive breeding followed by reintroduction to the wild.
B) Establish a reserve that protects the population’s habitat.
C) Introduce new individuals transported from other populations of the same species.
D) Sterilize the least fit individuals in the population.

The amino acid tyrosine is a starting substrate for the synthesis of _____.
A) epinephrine
B) steroid hormones
C) parathyroid hormone
D) acetylcholine

Based on this tree, which statement is NOT correct?

A) The salamander lineage is a basal taxon.
B) Salamanders are a sister group to the group containing lizards, goats, and humans.
C) Salamanders are as closely related to goats as to humans.
D) Lizards are more closely related to salamanders than to humans.

Which of the following descriptions best fits the class of molecules known as nucleotides?
A) a nitrogenous base and a phosphate group
B) a nitrogenous base and a sugar
C) a nitrogenous base, a phosphate group, and a sugar
D) a sugar and a purine or pyrimidine