With Complete Solutions
________ are weak bonds that are not strong
enough to hold atoms together to form molecules
but are strong enough to form bonds within and
around large molecules.
a. ionic bonds
b. covalent bonds
c. hydrogen bonds
d. polar covalent conds Correct Answers c.
hydrogen bonds
A child is born with a rare disease in which
mitochondria are missing from skeletal muscle
cells. However, the muscles still function.
Physicians find that the
a. muscle cells cannot split glucose to pyruvate.
b. muscles contain large amounts of lactate
following even mild physical exercise.
c. muscles contain large amounts of carbon dioxide
following even mild physical exercise.
d. muscles require extremely high levels of oxygen
to function. Correct Answers b. muscles contain
large amounts of lactate following even mild
physical exercise.
A child is brought to the hospital with a fever of
107°F. Doctors immediately order an ice bath to
lower the child's temperature. Which of the
,following statements offers the most logical
explanation for this action?
a. Elevated body temperatures will increase the
energy of activation needed to start various
chemical reactions in the body. This will interfere
with the ability of enzymes to catalyze vital
chemical reactions.
b. Elevated body temperature will increase
reaction rates in the child's cells and overload the
limited number of enzymes found in the cell.
c. Elevated body temperatures cause molecules to
vibrate more quickly and prevent enzymes from
easily attaching to reactants. This would slow vital
body reactions.
d. Elevated body temperatures may denature
enzymes. This would interfere with the cell's
abilities to catalyze various reactions. Correct
Answers d. Elevated body temperatures may
denature enzymes. This would interfere with the
cell's abilities to catalyze various reactions.
A culture of bacteria is fed glucose containing
radioactive carbon and is then examined. During
the citric acid cycle, radioactive carbon would first
appear in
a. NADH
b. oxaloacetate
c. CO2
d. citrate Correct Answers d. citrate
,A diet high in animal products and hydrogenated
vegetable margarine may increase the risk for
heart disease. This is because
a. most animal fats are used for energy storage
and most hydrogenated vegetable margarines
contain high levels of unsaturated fats.
b. most animal fats are saturated and many
hydrogenated vegetable margarines contain high
levels of trans fats.
c. most hydrogenated vegetable margarines are
hydrogenated oils and most animal products
contain high levels of phospholipids.
d. most animal fats are unsaturated and most
hydrogenated vegetable margarines contain high
levels of steroids. Correct Answers b. most animal
fats are saturated and many hydrogenated
vegetable margarines contain high levels of trans
fats.
A drug that interferes with microtubule formation is
likely to completely disrupt
a. the function of lysosomes
b. contraction of muscle cells
c. the amoeboid motion of a cell
d. the movements of sperm cells Correct Answers
d. the movement of sperm cells
A group of single-cell organisms collected from the
ocean was brought into the lab for examination.
The lab assistant was concerned that the water
, had become full of toxic waste products and so
added clean water to the culture. All of the
organisms died, and when she looked at them
under the microscope, all she could see were bits
and pieces of them scattered throughout the
water. What likely happened?
a. She added seawater to which she had added too
much salt, and they ruptured.
b. She added too little salt to the seawater she
added, and the organisms all lost too much water
and shriveled up.
c. She added water that was hypotonic to the
culture of organisms, and they ruptured.
d. She added water isotonic to the organisms,
causing too much water to move in and out of the
organisms, and they ruptured. Correct Answers c.
She added water that was hypotonic to the culture
of organisms, and they ruptured.
A manufacturing company dumps its wastes into a
nearby pond. One of the wastes is found to
paralyze the contractile vacuoles of certain
protists. A biologist looking at individual samples of
these organisms taken from the pond would find
that they
a. have died of malnutrition.
b. have died because wastes have built up in the
cytoplasm.
c. have gained water and burst.