What is the fundamental difference between covalent and ionic bonding?
A) In a covalent bond, the partners share a pair of electrons; in an ionic bond, one
partner accepts electrons from the other.
B) In covalent bonding, both partners end up with filled outer electron shells; in ionic
bonding, one partner does and the other does not.
C) Covalent bonding involves only the outermost electron shell; ionic bonding also
involves the next electron shell inside the outermost shell.
D) Covalent bonds form between atoms of the same element; ionic bonds form between
atoms of different elements.
Which of the following animals would be most likely to be able to effectively exchange
gases when placed in a dry desert environment?
A) an earthworm
B) a dolphin
C) a sea snail
D) a tuna fish
The first step in the formation of urine is the
A) secretion of hydrogen ions into the kidney tubules.
B) formation of filtrate that enters Bowman’s capsule.
C) secretion of urea into the renal pelvis.
D) reabsorption of nutrients by Bowman’s capsule.
Which of the following is a hormone produced by adipose cells that helps to control
appetite?
A) insulin
B) bile
C) gastrin
D) leptin
What occurs during gastrulation?
A) A solid embryo is changed into a hollow morula.
B) A solid blastula is changed into a hollow embryo that has four tissue layers.
C) A hollow blastula is changed into a hollow embryo that has three tissue layers.
D) A neural tube is created by invagination of the ectoderm.
An ecologist hypothesizes that predation by a particular owl species is the major factor
controlling the population of a particular rabbit species. If this is the case, which of the
following population effects could be expected in this rabbit-owl pair?
A) A fall in the owl population should cause a fall in the rabbit population.
B) A fall in the rabbit population should cause an increase in the owl population.
C) An increase in the incidence of disease in the rabbit population should not change
the owl population.
D) An increase in the owl population should cause a fall in the rabbit population.
During the 1950s, a scientist named Lysenko tried to solve the food shortages in the
Soviet Union by breeding wheat that could grow in Siberia. He theorized that if
individual wheat plants were exposed to cold, they would develop additional cold
tolerance and pass it to their offspring. Based on the ideas of artificial and natural
selection, do you think this project worked as planned?
A) Yes; the wheat probably evolved better cold tolerance over time through inheritance
of acquired characteristics.
B) No, because Lysenko took his wheat seeds straight to Siberia instead of exposing
them incrementally to cold.
C) No, because there was no process of selection based on inherited traits. Lysenko
assumed that exposure could induce a plant to develop additional cold tolerance and
that this tolerance would be passed to the plant’s offspring.
D) Yes, because this is generally the method used by plant breeders to develop new
crops.
The role of a control in an experiment is to
A) provide a basis of comparison to the experimental group.
B) prove that a hypothesis is correct.
C) ensure repeatability.
D) counteract the negative effect of the experiment.
There is a mutation in a promoter next to a gene such that RNA polymerase can never
bind. What steps must occur for the gene to be transcribed?
A) An activator protein must bind an enhancer.
B) The DNA must physically bend so that the activator is close to the promoter.
C) Transcription factors must bind to the activator and promoter.
D) Transcription will never take place in this specific example.
The feature of ‘sticky ends” that makes them especially useful in DNA recombination is
their ability to
A) bind to DNA and thereby activate transcription.
B) bind to ribosomes and thereby activate translation.
C) form hydrogen-bonded base pairs with complementary single-stranded stretches of
DNA.
D) allow plasmids to attach to the main bacterial chromosome.
Researchers have created a robot that has a very thin leg that is moved by cardiac
(heart) cells contracting in unison. The robot, made of a polymer similar to that used in
making contact lenses, is bathed in heart cells with supporting fibroblasts, which then
attach to the robot and provide movement as they contract.
All of the cardiac cells working together can cause the robot leg to move in a way that
individual cells could not. This is an example of
A) adaptation.
B) emergent properties of cells.
C) energy flow through an ecosystem.
D) internal environment regulation.
The main function of the inflammatory response is to
A) initiate the production of antibodies.
B) remove contaminating microorganisms and initiate repair of damaged tissues.
C) initiate T cell-mediated immune responses.
D) initiate the production of killer cells.
The “one gene-one polypeptide” theory states that
A) the synthesis of each gene is catalyzed by one specific enzyme.
B) the synthesis of each enzyme is catalyzed by one specific gene.
C) the function of an individual gene is to dictate the production of a specific
polypeptide.
D) the function of each polypeptide is to regulate the synthesis of each corresponding
gene.
Household ammonia, or ammonium hydroxide, is a mixture of ammonia (NH3) and
water. What types of bonding interactions will occur between molecules of ammonia
and water in a bottle of household ammonia?
A) polar covalent bonds between positively charged nitrogen atoms in ammonia and
negatively charged oxygen atoms in water
B) polar covalent bonds between negatively charged nitrogen atoms in ammonia and
positively charged hydrogen atoms in water
C) hydrogen bonds between positively charged nitrogen atoms in ammonia and
negatively charged oxygen atoms in water
D) hydrogen bonds between negatively charged nitrogen atoms in ammonia and
positively charged hydrogen atoms in water
Which of the following will tend to produce adaptive changes in populations?
A) genetic drift
B) gene flow
C) natural selection
D) the founder effect
Which of the following statements, according to this figure, is true?
A) The efficiency of corn production (yield per area) in the United States has increased
more than global efficiency.
B) The efficiency of global corn production (yield per area) has increased more than
efficiency in the United States.
C) Global production efficiency was greater prior to 1980 than since 1980.
D) The efficiency of U.S. production has decreased.
Cells migrate from one place to another during gastrulation using
A) cilia.
B) cellular protrusions.
C) flagella.
D) peristalsis.
Threadlike fungal filaments are called
A) mycelia.
B) hyphae.
C) vascular bundles.
D) mold.
Which of the following is a trace element in the human body?
A) nitrogen
B) zinc
C) oxygen
D) hydrogen
About one-third of all animal and plant species are concentrated on ________ of Earth’s
land.
A) 20%
B) 10%
C) 5%
D) 1.5%
In this drawing of the lac operon, which molecule is an inactive repressor?
A) molecule A
B) molecule B
C) molecule C
D) molecule D
Which of the following is associated with a reduced risk of cardiovascular disease?
A) high levels of HDL
B) high levels of LDL
C) high consumption of trans fats
D) high consumption of dietary cholesterol
The body cells of a turkey have 80 chromosomes each. How many chromosomes would
be found in a male turkey’s sperm cells?
A) 160
B) 80
C) 40
D) 20
Which of the following cellular structures is characteristic of amoebas?
A) pseudopodia
B) microvilli
C) cilia
D) flagella
Below are the structures of three fatty acids, palmitic acid, stearic acid, and oleic acid.
What combination of these fatty acids could you use to make a fat that is liquid at room
temperature?
A) one palmitic acid, one stearic acid, and one oleic acid
B) three palmitic acids
C) two palmitic acids and one stearic acid
D) one stearic acid, one oleic acid, and one phosphate group
The brain and spinal cord are formed from
A) the notochord, which is formed from mesoderm.
B) the notochord, which is formed from endoderm.
C) the neural tube, which is formed from mesoderm.
D) the neural tube, which is formed from ectoderm.
The role of calcium in muscle contraction is to
A) release ADP and phosphate from myosin.
B) make it possible for ATP to bind to actin.
C) make it possible for myosin to bind to actin.
D) make it possible for ATP to bind to myosin.
You are a member of an African family that has been displaced from their home by civil
war, so you are trying to select a new country in which to settle to gain better economic
opportunities. You know that Nigeria is a large country with rich natural resources, so
you are considering it for your new home. Among the data you find while researching
Nigeria is the following diagram of the current age structure of the country.
The age structure data for Nigeria shows that the country has many more individuals
under the age of 15 than over the age of 40. What does this imply about the future
population of Nigeria?
A) The population will probably remain stable.
B) The population will probably decrease.
C) The population will probably grow rapidly.
D) The number of older people will probably increase rapidly.
Which of the following options correctly lists the order of the four main processes that
occur in the urinary system?
A) filtration, excretion, reabsorption, secretion
B) excretion, filtration, reabsorption, secretion
C) filtration, reabsorption and secretion occurring simultaneously, excretion
D) reabsorption and secretion occurring simultaneously, excretion, filtration
If ATP accumulates in a cell,
A) the cell receives a signal that there is a need for more energy.
B) feedback inhibition speeds up cellular respiration.
C) feedback inhibition slows down cellular respiration.
D) the rate of cellular respiration does not change.