Solved by a verified expert:Question 1 of 48
3.75 Points
Decondensed chromatin is located within the
A.nucleolus during maintenance
B.nucleus during cell maintenance
C.nucleus during cell division
D.nucleolus during cell division Reset Selection

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Question 2 of 48
3.75 Points
The evil arch-villain Dr. Black Thumb has
created a new plant pathogen. The microbe has an enzyme allowing it to quickly
convert β 1-4 glycosidic linkages to α 1-4 glycosidic linkages in a whole field
of plants. If Dr. Black Thumb’s plan is not thwarted, crop harvests could be
ruined due to
A.amylose and amylopectin becoming hard and
inedible.
B.plant starches becoming rigid and popping
cell membranes.
C.
plants flopping over.
D.polysaccharides converting into monosaccharides. Reset Selection

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Question 3 of 48
3.75 Points
An atom with an atomic mass of 89 and an
atomic number of 39 has how many
neutrons?
A.128
B.2
C.50
D.59 Reset Selection

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Question 4 of 48
3.75 Points
What factors allow a pool of 20 amino acids
to produce thousands of unique proteins? (Select all that apply.)
A.
variation in length of amino acid backbone
B.
each protein is encoded by a distinct gene
C.
variation in tertiary structure
D.
variations in which amino acids are used
E.
variations in glycosidic linkage
F.
variations in the type of peptide bond
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Question 5 of 48
3.75 Points
_________________ prevent material from
moving in or out of the brain’s capillaries
A.Desmosomes
B.Plasmodesmatas
C.Gap junctions
D.Tight junctions Reset Selection

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Question 6 of 48
3.75 Points
Cardiac muscle requires junctions that
allow electrical signals through. Cardiac muscle also relies on calcium to
contract. What junction is involved and what organelle stores calcium?
A.desmosomes, smooth ER
B.plasmodesmata, rough ER
C.gap, smooth ER
D.tight, rough ER Reset Selection

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Question 7 of 48
3.75 Points
The building blocks of nucleic acids are
A.sugars.
B.nucleotides.
C.peptides.
D.nitrogenous bases. Reset Selection

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Question 8 of 48
3.75 Points
Which statements describe sodium atoms?
Select all that apply.
A. forms
cations
B.
closest to the left side of the periodic table
C.
easily forms covalent bonds
D.
contains 1 valence electron
E.
has 2 electrons in the first energy level
F.
can lose one electron easily
G.
outer energy level is stable
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Question 9 of 48
3.75 Points
If an integrin protein is mutated what cell
function might be affected?
A.communication between cytoskeleton and
proteglycan
B.fluidity of phospholipids
C.cellular motility
D.cytoplasmic communication Reset Selection

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Question 10 of 48
3.75 Points
Buffers are important for doing experiments
in labs, but they are not relevant to living systems.
True
False
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Question 11 of 48
3.75 Points
The cell theory states
A.all cells will contain DNA, all cells are
the smallest living things that can divide and all organisms are composed of
cells
B.all organisms are composed of multiple
cells, all cells arise spontaneously and all cells require nutrients
C.all cells are the smallest living things,
all organisms are composed of one or more cells and all cells arise
spontaneously
D.all organisms are composed of one or more
cells, all cells are the smallest living things and all cells arise from other
cells Reset Selection

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Question 12 of 48
3.75 Points
Hiking in the snowy woods, you peek inside
a cave and encounter a hibernating grizzly bear! Its metabolic rate seems to be
very low. What do you predict is the predominant type of reaction occurring in
this bear?
A.fatty acid anabolism
B.carbohydrate catabolism
C.carbohydrate anabolism
D.fatty acid catabolism Reset Selection

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Question 13 of 48
3.75 Points
Rosenberg, a chemist, was observing the
effects of an electric field on bacterial growth. He observed that bacteria
stopped dividing when in an electric field. This research led to the
anti-cancer drug cisplatin, a platinum containing compound. Rosenberg’s
discovery was an example of
science.
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Question 14 of 48
3.75 Points
Enzymes are catalysts in reactions. What
statements describe functions of enzymes? Select all that apply.
A.
Enzymes are specific in their actions.
B.
Once an enzyme binds to a substrate, it cannot be used again.
C.
Enzymes lower the energy of activation needed for a reaction
D.
Enzymes change the amount of free energy produced
E.
Enzyme activity can be affected by temperature.
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Question 15 of 48
3.75 Points
In biological macromolecules like proteins,
the hydrophobic residues tend to clump together in the interior of the folded
structure. What is the best explanation for why this occurs?
A.Polar residues tend to bind to water in the
cytoplasm as well as to each other. The water and polar residues cannot bind to
the hydrophobic ones, so in the lowest energy state the hydrophobic residues
are pushed together in the middle.
B.Protein folding machinery interprets the amino
acid code to pack hydrophobic residues into the center of proteins. This
process must be important, because the cell expends large amounts of ATP to
precisely coordinate protein folding.
C.Hydrophobic residues bind to each other in
specific ways. For instance, Ala forms di-methyl bonds, and phenylalanine binds
isoleucine. This creates a tightly bound hydrophobic inner core.
D.Hydrophobic residues bind each other, while
polar residues cannot bind each other. Therefore the hydrophobic ones end up stuck
to each other in the core of the protein. Reset
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Question 16 of 48
3.75 Points
If two solutions are different, the one
will the higher concentration of solutes is
A.isotonic
B.hypertonic
C.hypotonic Reset
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Question 17 of 48
3.75 Points
You are designing a museum exhibit to teach
people about cells. In the entrance to the exhibit, visitors riding a moving
walkway under flashing lights will gradually “shrink” down in size. To create
this illusion, visitors will pass giant models of various biological parts,
accompanied by scale bars.
Match each model to the appropriate scale
bar to go with it.
A. 1 μm
B. 1nm
C. 10μm
D. 1cm
E. 1m
F. 0.1 nm
1.
Carbon atom
2.
cell nucleus
3.
DNA molecule (10bp)
4.
human being
5.
human eyeball
6.
skin cell
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Question 18 of 48
3.75 Points
The fluid mosaic model describes membranes
as fluid due to
A.phospholipids sporadically placed throughout
the membrane
B.the membrane is mostly composed of water
C.the proteins and the phospholipids can move
laterally throughout the membrane
D.higher amounts of cholesterol
E.higher amounts of cholesterol Reset Selection

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Question 19 of 48
3.75 Points
Cholera kills over 100,000 people each year
worldwide due to diarrhea. The cholera toxin opens the CFTR chloride channel in
the intestines, so that sufferers lose chloride, sodium and massive amounts of
water.
On the other hand, the same CFTR channel is
mutated in cystic fibrosis patients. With activity too LOW, they lack chloride
flow and mucus builds up in the lungs.
This illustrates the importance of precise
control of channel opening, known as
____________regulation.
A.gated
B.ungated
C.passive Reset
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Question 20 of 48
3.75 Points
When viewing the shape of a human cheek
cell, what microscope would most likely be used?
A.light
B.dissecting
C.transmission electron
D.scanning electron Reset Selection

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Question 21 of 48
3.75 Points
At a meal, you are served a hamburger with
cheese, onions, and beef on a bun. What ingredients represent the most
carbohydrates? Select all that apply.
A.
beef
B.
bun
C.
onion
D.
cheese
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Question 22 of 48
3.75 Points
Estrogen and testosterone are structurally
related to cholesterol. Based on what you have learned about cholesterol,
predict how these steroid hormones signal to the cell.
A.They are phagocytosed, degraded, and then
released into the cell.
B.They make the membrane so fluid that small
pores appear, allowing them to pass through.
C.They diffuse directly through the plasma
membrane and into the cell.
D.They bind to receptors on the outside of the
membrane, which then activate an intracellular signaling cascade. Reset Selection

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Question 23 of 48
3.75 Points
Noncompetitive inhibition occurs when
A.a
substance binds at the activity site
B.a
substance binds on a site away from the active site
C.denaturing an enzyme
D.increasing the activity of an enzyme Reset Selection

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Question 24 of 48
3.75 Points
Organisms must use macromolecules that have
properties to match their functional requirements. In the list below, choose
the appropriate macromolecule whose properties meet the requirement.
A. glycogen
B. RNA
C. DNA
D. cellulose
E. starch
1.
Requirement:
Strong cell walls

Properties:
Linear polymer rigid and strong
2.
Requirement
Stable storage of information

Properties:
4 base pairs, not easily hydrolyzed
3.
Requirement:
Energy storage for seeds
Properties:
Energy-rich polysaccharides
4.
Requirement:
Short-term energy storage (animals)
Properties:
Energy-rich polysaccharide
5.
Requirement:
Transient transmission of information
Properties:
4 base pairs, easily hydrolyzed
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Question 25 of 48
3.75 Points
Membrane proteins are able to cross because
sections are composed of
A.nonpolar phosphate regions
B.hydrophilic amino acids.
C.hydrophobic amino acids
D.polar amino acids
E.hydrophilic phosphate regions Reset Selection

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Question 26 of 48
3.75 Points
The shape of the cell is predominantly
maintained by the
A.plasma membrane
B.cytoskeleton
C.cytoplasm
D.endomembrane system Reset Selection

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Question 27 of 48
3.75 Points
What is the function of cholesterol in
plasma membranes?
A.allows ions to pass
B.regulates pH
C.promotes artherosclerosis
D.regulates fluidity Reset Selection

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Question 28 of 48
3.75 Points
When donating blood, hemoglobin levels are
measured by using a narrow glass tube to obtain blood from a finger prick. The
blood is pulled up the tube by _____________________.
A.cohesiveness
B.covalent bonds
C.hydrophobic interactions
D.hydrogen bonds
E.ionic bonds Reset
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Question 29 of 48
3.75 Points
What protein is matched with its function?
A.aquaporins – move water through the membrane
by active transport
B.carrier protein – nonspecific and will allow
material to pass directly through
C.channel protein – allow passage of material
through the hydrophilic pore
D.transport proteins – allow passage of
material with the aid of ATP

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Question 30 of 48
3.75 Points
C6H12O6 + 6O2 à 6H2O + 6CO2 is an example
of ________________.

A.catabolism
B.anabolism
C.synthesis Reset
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Question 31 of 48
3.75 Points
Carbon-12, Carbon-13, and Carbon-14 are
examples of

A.isomers
B.molecules
C.ions
D.isotopes
E.enantiomers Reset
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Question 32 of 48
3.75 Points
What statement(s) describes a concentration
gradient?
A.
Oxygen in blood plasma is .31 per 100 ml. Oxygen carried with hemoglobin is .69
per 100 ml.
B.
Extracellular fluid contains 13.5 mmol of calcium, and 9 mmol of calcium is in
the plasma.
C.
The temperature inside the car is 39 degrees Celsius and the temperature
outside the care is 39 degree Celsius.
D.
Red blood cells cytoplasm contains a 0.9% salt solution. The extracellular
fluid is 1.0%.
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Question 33 of 48
3.75 Points
How can ice float?
A.the covalent bonds expand, decreasing
density
B.the hydrogen bonds expand, decreasing
density
C.the covalent bonds collapse, increasing
density
D.the hydrogen bonds collapse, increasing
density Reset Selection

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Question 34 of 48
3.75 Points
Which of the following form the foundation
of plasma membranes?
A.Glycoproteins
B.Fatty acids
C.Glycolipids
D.Phospholipids
E.Proteins Reset
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Question 35 of 48
3.75 Points
You and your roommate are grocery shopping.
“I don’t get it,” she says. “My doctor said I should buy this special milk
because I don’t digest it well. But this brand says ‘lactose-free’ and this
brand says ‘lactase added’ – which do I want?”
You reply: “The
_______________ is a sugar in milk that you
have trouble digesting, and
_________________ is an enzyme that will
digest it for you.
A.lactase,
lactose
B.lactose,lactase Reset Selection

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Question 36 of 48
3.75 Points
If sodium does not move down its gradient
in the co-transport pump, what would be the outcome?
A.Sugar would not be affected
B.Sugar would not be able to move down the
gradient
C.Sugar would not be able to move up the
gradient Reset Selection

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Question 37 of 48
3.75 Points
When phospholipids are placed in water, why
does a bilayer form?
A.Phospholipids are naturally attracted to
each other, forcing phosphate heads to face the aqueous areas.
B.The fatty acid tails are forced together
away from the water, and water can create hydrogen bonds with the phosphate
heads.
C.Lipids are hydrophilic and will from hydrogen
bonds with the water, forcing the hydrophobic heads towards the middle of the
bilayer.
D.The polar tails will be attracted to the
water and the nonpolar heads will be attracted to each other. Reset Selection

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Question 38 of 48
3.75 Points
To break chemical bonds to start a chemical
reaction, ___________ energy is needed.
A.kinetic
B.potential
C.activation
D.free Reset
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Question 39 of 48
3.75 Points
The microbiologist Louis Pasteur invented
pasteurization, created vaccines for anthrax and rabies, and helped explain the
germ theory of disease. He is often quoted as saying, “Chance favors the
prepared mind.” A more accurate translation from the French, however, is “Where
observation is concerned, chance favors only the prepared mind.” What can you
conclude about Pasteur’s attitude about the role of chance in scientific
discovery?
A.He
thought that chance events are only useful if someone is intelligent enough to
understand what happened.
B.He
thought that observation of something unique doesn’t do any good if the
scientist is not prepared to interpret and follow up on the chance discovery,
due to a habit of studious work.
C.He
thought you would have to be lucky to notice a chance event.
D.He
thought that chance is the main determinant of who is successful in science, so
all you can do is hope you get lucky. Reset
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Question 40 of 48
3.75 Points
A tarantula has eight legs, an arachnid in
the order Araneae. A grass spider has eight legs, an arachnid in the order
Araneaa. A mouse spider has eight legs, an arachnid in the order Araneae. There
is a pattern. All organisms in this order have eight legs. This is

reasoning
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Question 41 of 48
3.75 Points
In a chocolate bar with nuts and caramel,
there are 12 grams of fat, 33 grams of carbohydrates and 4 grams of protein.
What percentage of calories comes from fat?
A.6.5%
B.19%
C.53%
D.41 Reset Selection

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Question 42 of 48
3.75 Points
Normal (homeostatic) pH level of blood
serum’s pH is around 7.4. Carbonic acid is released in the blood to help
maintain a pH that has high hydroxyl levels. This would cause pH to change from
A.basic
to acidic
B.basic to neutral
C.neutral to basic
D.acidic to 7.4
E.basic to 7.4 Reset
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Question 43 of 48
3.75 Points
What is the pathway in which a protein
moves through the endomembrane system?
A.rough ER, Golgi apparatus, smooth ER,
transport vesicle, plasma membrane
B.plasma membrane, transport vesicle, Golgi
apparatus, rough ER
C.rough ER, Golgi apparatus, transport
vesicle, plasma membrane
D.smooth ER, Golgi apparatus, transport
vesicle, plasma membrane Reset
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Question 44 of 48
3.75 Points
Molecules move from a high to low
concentration in
A.isotonic solutions
B.hypotonic solutions
C.hypertonic solutions
D.diffusion
E.osmosis Reset
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Question 45 of 48
3.75 Points
What examples describe the second law of
thermodynamics? Select all that apply.
A. A
penny will fall when you pick it up and let it drop.
B. A
frying pan is on a hot stove. When removed it will cool.
C.
Ice cubes will melt in a warm room.
D.
Donuts nutrients are used to help you exercise.
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Question 46 of 48
3.75 Points

Researchers are working to develop biofuels
to free us from dependence on fossil fuels. Based on what you know about
cellulose, what do you predict are the major advantage and disadvantage of
using cellulose-rich plant material as biofuel?
A.There is not much energy in the glycosidic
bonds of cellulose, but at least there is a lot of it.
B.There is not much energy in the peptide
bonds of cellulose, but at least it is very easy to break down
C.The breakdown of cellulose into fructose is
an endergonic reaction, but an enzyme can reverse the equilibrium.
D.Cellulose is very difficult to break down
into glucose, but it contains a lot of energy. Reset
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Question 47 of 48
3.75 Points
The impermeability of cell plasma membranes
is a major barrier to using drugs to kill tumor cells or affect cells
transgenically. CPPs are peptides that were discovered to have the ability to
transport themselves (and even attached cargo) into cells. How they get into
cells is still a mystery, but CPPs all have multiple positively charged groups.
Which of the following membrane components are they most likely to be
interacting with?
A.cholesterol
B.intrinsic membrane proteins
C.phospholipid heads
D.phospholipid tails Reset Selection

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Question 48 of 48
3.75 Points
Which of the following is an example of an
aliphatic hydrocarbon?
A.Benzene
B.Estrogen
C.Cholesterol
D.Methane