Deck 5: The Working Cell

Question 1

You have a 2-kg bottle of liquid water at 0°C. About how many Calories are needed to heat up the water to 100°C?

A)100 Calories
B)200 Calories
C)2,000 Calories
D)10,000 Calories

Answer 1

B

Question 2

Usually, enzymes are ________.

A)fats
B)steroids
C)chemical reactions
D)proteins

Answer 2

D

Question 3

Which statement about enzymes is TRUE?

A)Enzymes are the products in a chemical reaction.
B)Enzymes are the reactants in a chemical reaction.
C)Enzymes catalyze specific reactions.
D)Enzymes' functions require inhibitors.

Answer 3

C

Question 4

Enzymes increase the rate of a reaction by ________.

A)increasing the temperature of the substrates
B)taking energy from reactants and transferring it to products
C)decreasing activation energy
D)binding to a substrate imposter

Question 5

The combination of sucrose, sucrase, and water produces sucrase, glucose, and fructose. Which component of the reaction is the enzyme?

A)sucrose
B)sucrase
C)glucose
D)fructose

Question 6

Anything that prevents ATP formation will most likely ________.

A)result in cell death
B)force the cell to rely on lipids for energy
C)force the cell to rely on ADP for energy
D)have no effect on the cell

Question 7

Which of the following is a measure of randomness in a system?

A)entropy
B)calorie
C)potential energy
D)chemical energy

Question 8

An object at rest has no ________ energy, but it may have ________ energy resulting from its location or structure.

A)kinetic; potential
B)kinetic; heat
C)potential; kinetic
D)chemical; potential

Question 9

The principle that energy cannot be created or destroyed is known as ________.

A)cellular respiration
B)conservation of energy
C)conservation of heat
D)entropy

Question 10

Humans convert approximately ________ of the energy stored in food to useful work.

A)22%
B)34%
C)55%
D)99.9%

Question 11

What molecules are scientists currently trying to use to generate power for nanotechnology devices, such as microscopic robots?

A)DNA
B)enzymes
C)lipids
D)cell membranes

Question 12

What compound directly provides energy for cellular work?

A)sugar
B)ATP
C)DNA
D)fat

Question 13

Energy can be defined as ________.

A)the capacity to cause movement
B)the capacity to cause change
C)a measure of calories
D)a measure of disorder

Question 14

Glucose molecules provide energy to power the swimming motion of sperm. In this example, the sperm are changing ________.

A)chemical energy into kinetic energy
B)chemical energy into potential energy
C)kinetic energy into potential energy
D)kinetic energy into chemical energy

Question 15

The sum total of all the chemical reactions that occur in organisms is called ________.

A)kinetic energy
B)cellular synthesis
C)conservation of energy
D)metabolism

Question 16

A boulder at the top of a hill contains ________ energy.

A)potential
B)no
C)kinetic
D)conserved

Question 17

ATP energizes other molecules in cells by transferring a(n)________ to those molecules.

A)adenosine
B)heat unit
C)ADP
D)phosphate group

Question 18

An enzyme's function is most dependent on its ________.

A)activation energy
B)temperature
C)shape
D)size

Question 19

Ten kilocalories are equivalent to ________ calories.

A)1,000
B)10,000
C)0)1
D)100

Question 20

You are riding on your bike and stop pedaling, coasting along the road. Eventually, your bike slows down and stops. What happened to the energy of your motion when your bike stopped?

A)It was returned to the bicycle.
B)It was converted back to chemical energy.
C)It was released as heat.
D)It was used to chemically break down the tires.

Question 21

The combination of sucrose, sucrase, and water produces sucrase, glucose, and fructose. Which component of the reaction is the substrate?

A)sucrose
B)sucrase
C)glucose
D)fructose

Question 22

A balloon that is permeable to water but not to glucose contains a 10% glucose solution. A beaker contains a 5% glucose solution. Which statement correctly classifies the solutions?

A)The solution in the beaker is hypertonic relative to the solution in the balloon.
B)The solutions in the balloon and the beaker are isotonic to each other.
C)The solution in the balloon is hypotonic relative to the solution in the beaker.
D)The solution in the balloon is hypertonic relative to the solution in the beaker.

Question 23

Which statement about an enzyme is TRUE?

A)An enzyme's function depends on its three-dimensional shape.
B)An enzyme works on a broad range of substrates.
C)An enzyme is used up in chemical reactions.
D)An enzyme becomes another enzyme after a reaction.

Question 24

Specialized cells that line the stomach synthesize a digestive enzyme and secrete it into the stomach. Which process could be responsible for its secretion?

A)endocytosis
B)exocytosis
C)phagocytosis
D)passive transport

Question 25

Facilitated diffusion across a biological membrane requires ________ and moves a substance ________ its concentration gradient.

A)energy; down
B)transport proteins; down
C)energy and transport proteins; against
D)transport proteins; against

Question 26

Diffusion is an example of ________.

A)phagocytosis
B)active transport
C)endocytosis
D)passive transport

Question 27

Some protozoans have special organelles called contractile vacuoles that continually eliminate excess water from the cell. The presence of these organelles tells you that the environment ________.

A)is isotonic to the protozoan
B)is hypotonic to the protozoan
C)is hypertonic to the protozoan
D)contains a higher concentration of solutes than the protozoan

Question 28

When two solutions that differ in solute concentration are placed on either side of a selectively permeable membrane, and osmosis is allowed to take place, the water will ________.

A)exhibit a net movement to the side with lower water concentration
B)exhibit a net movement to the side with higher water concentration
C)exhibit a net movement to the side with lower solute concentration
D)exhibit an equal movement in both directions across the membrane

Question 29

Osmosis can be defined as ________.

A)the diffusion of water across a selectively permeable membrane
B)the diffusion of any small molecule across a selectively permeable membrane
C)active transport across a selectively permeable membrane
D)the diffusion of a solute across a selectively permeable membrane

Question 30

Substances that plug up an enzyme's active site are enzyme ________.

A)substrates
B)inhibitors
C)catalysts
D)products

Question 31

When a person cries, tears are exported from cells. Which category of transport most precisely matches this process?

A)facilitated diffusion
B)active transport
C)endocytosis
D)exocytosis

Question 32

Diffusion ________.

A)is the result of an energy transformation
B)requires an input of cellular energy
C)occurs when particles spread from areas where they are less concentrated to areas where they are more concentrated
D)proceeds until a dynamic equilibrium is reached

Question 33

A balloon contains a 10% glucose solution. The balloon is permeable to water but not to glucose. A beaker contains a 5% glucose solution. What will happen when the balloon is submerged in the beaker?

A)The volume of water in the beaker will decrease.
B)The volume of water in the beaker will increase.
C)The amount of glucose in the beaker will increase.
D)The amount of glucose in the beaker will decrease.

Question 34

________ occurs when a white blood cell engulfs a bacterium.

A)Osmosis
B)Diffusion
C)Exocytosis
D)Phagocytosis

Question 35

Which process could result in the net movement of a substance into a cell, if the substance is more concentrated in the cell than in the surroundings?

A)active transport
B)facilitated diffusion
C)diffusion
D)osmosis

Question 36

A cell that neither gains nor loses a net amount of water at equilibrium when it is immersed in a solution is ________.

A)isotonic to its environment
B)hypertonic to its environment
C)hypotonic to its environment
D)metabolically inactive

Question 37

Active transport ________.

A)does not use ATP as an energy source
B)moves solutes with their concentration gradient
C)can involve the transport of ions
D)is a type of facilitated diffusion

Question 38

In a hypotonic solution, a plant cell will ________.

A)undergo plasmolysis
B)become flaccid
C)burst
D)become turgid

Question 39

If placed in tap water, an animal cell will undergo lysis, whereas a plant cell will not. What accounts for this difference?

A)expulsion of water by the plant cell's central vacuole
B)inability of water to cross a plant cell membrane
C)impermeability of the plant cell wall to water
D)relative inelasticity and strength of the plant cell wall

Question 40

The region of an enzyme to which a substrate binds is called the ________ site.

A)active
B)substrate
C)inhibition
D)lactase

Question 41

What would be the best experiment to test the effectiveness of this anticancer drug system?

A)Inject both sets of liposomes into a single healthy mouse and measure what happens to its blood ATP levels.
B)Inject both sets of liposomes into a single mouse that has tumors and measure what happens to the size of the tumors.
C)Inject both sets of liposomes into multiple healthy mice and measure what happens to their blood ATP levels.
D)Inject both sets of liposomes into multiple mice that have tumors and measure what happens to the size of the tumors.

Question 42

How are membrane transport proteins like enzymes?

A)Both are specialized to the materials they act upon.
B)Both are made from RNA molecules.
C)Both require energy to function properly.
D)Neither can change as a result of gene mutations.

Question 43

Read the following scenario to answer the following question(s).
Biomedical scientists have recently developed an anticancer drug delivery system that sneaks the anticancer drug into cancer cells before releasing it. They were able to do this by using two sets of liposomes. An anticancer drug (Doxorubicin (Dox))bound to DNA molecules was added into one set of liposomes, and a high concentration of ATP molecules were added to the other set of liposomes. The drug is inactive when bound to DNA molecules. Researchers inject both types of liposomes into cancer cells, and upon doing so their contents are released. The ATP molecules from one set of liposomes bind to the DNA molecules from the other set of liposomes)and activate the drug, thus inducing cell death and decreasing tumor size.
Mice with breast cancer tumors were treated with this liposome system to test the effectiveness of the drug. The scientists performed three trials-one with both types of liposomes (Dox + ATP), one with just the drug (Dox only), and one with a salt solution (control). Examine the figure below and answer the following questions.
Which statement regarding these data is TRUE?

A)The weight of the tumors did not change if treated with just the drug (Dox only)or both types of liposomes (Dox + ATP).
B)Tumor weight decreases when you add just the drug (Dox only)to cancer cells.
C)Adding just the drug (Dox only)or both types of liposomes (Dox + ATP)results in similar decreases in tumor weight.
D)Dox must be entering the cancer cells via endocytosis to induce cell death.

Question 44

Read the following scenario to answer the following question(s).
Cellular respiration converts the energy of fuel molecules to a form of energy that a cell can use to perform work. In an average day, most adult humans need to consume about 2,000 Calories to maintain their health. However, the exact amount of dietary Calories a person needs depends upon many factors, including the person's age, physical activity, size, and health. Foods that we consume vary greatly in their nutritional content and quality. A large hard-boiled egg, for example, has about 75 dietary Calories and contains about 70% of our recommended daily intake of cholesterol.
Molecules that come from the food we eat provide energy for the amazing work that goes on inside of our cells. This energy, stored inside of our food, is a form of ________.

A)potential energy called chemical energy
B)potential energy called entropy
C)kinetic energy called heat
D)electrical energy called heat

Question 45

How does the figure below represent the relationship between energy and ATP?

A)The addition of energy releases a phosphate group from ATP.
B)ATP can perform cellular work when it releases a phosphate group.
C)ATP can be converted to ADP by adding a phosphate group.
D)Energy is released from ATP during the process of cellular respiration.

Question 46

What biological process did scientists use as an inspiration for engineering enzymes to remove molecular tags from red blood cells?

A)natural selection
B)enzyme activation
C)endocytosis
D)phosphate transfer from ATP

Question 47

What cell transport is modeled by the diagram below?

A)A liver cell uses endocytosis to take up cholesterol from the blood.
B)A tear gland cell secretes a salty solution by exocytosis.
C)A neuron uses passive transport to export dopamine.
D)An immune cell engulfs virus particles using facilitated diffusion.

Question 48

Running burns approximately 600 Calories per hour. If you ate four hard-boiled eggs, how long would you have to run to burn them off?

A)10 minutes
B)30 minutes
C)60 minutes
D)120 minutes

Question 49

Which environments would be best for the functioning of animal and plant cells?

A)A hypotonic environment for plant cells and an isotonic environment for animal cells.
B)A hypotonic environment for animal cells and an isotonic environment for plant cells.
C)An isotonic environment for both plant and animal cells.

Question 50

Which of these molecules spontaneously form membranes when mixed in water and most likely were one of the first organic compounds formed on Earth?

A)DNA
B)enzymes
C)phospholipids
D)RNA

Question 51

A student in your class examines the graph and hypothesizes that ATP is what kills cancer cells, and not Dox. What follow-up experiment would allow you to test this student's hypothesis?

A)Add a fourth trial, in which mice with breast cancer tumors are treated with liposomes containing just ATP (ATP only).
B)Repeat the three trials described in the scenario until the tumor weights are the same from treatments with just Dox (Dox only)and both types of liposomes (Dox + ATP).
C)Treat mice with breast cancer tumors with liposomes containing both Dox and ATP together (not in separate liposomes).
D)Observe what happens to mice when ATP and Dox are combined in the absence of tumors.

Question 52

Directed evolution is a relatively new way to engineer enzymes. Previously, scientists tried to design proteins by using computer models to try to predict how specific changes in genetic sequences might result in altered enzyme structure and function. Why is one of these approaches more efficient than the other?

A)Generating high numbers of random mutations and subsequently screening for desired function means that directed evolution requires little prior knowledge of enzyme structure.
B)Computer models can produce many possible changes in genetic sequences in a short period of time, and then researchers can study each real enzyme one at a time.
C)Although the computer modeling method is slower and requires more information about the enzyme's genetic sequence, the function of enzymes produced by directed evolution is unknown.
D)Because directed evolution produces many genetic sequences that do not lead to improved activity, researchers have found that this procedure results in few successful results.

Question 53

In7 the figure below, how does the molecule labeled A affect enzyme function?

A)It is an inhibitor that changes the enzyme's active site.
B)It is a substrate imposter that keeps the regular substrate from binding.
C)It is a second substrate for an enzyme that works on two substrates.
D)It lowers the activation energy for the chemical reaction.

Question 54

Examine the cells below. Cells with a higher concentration of ions than the surrounding medium tend to ________.

A)stay about the same size and shape
B)expand
C)shrink
D)divide

Question 55

A person eats one hard-boiled egg and digests the egg fully. During cellular respiration MOST of the Calories in the egg is converted to ________.

A)ATP
B)heat
C)carbon dioxide
D)sugars

Question 56

What is the best explanation for the intermediate tumor size that results from treatment with just the drug (Dox only)compared to the control and treatment with both liposomes (Dox + ATP)?

A)Without ATP, Dox becomes an energy source for cancer cells.
B)Dox actually does not require ATP to be activated.
C)When ATP is lacking, not as much Dox can enter the cell via facilitated diffusion.
D)There is likely to be some ATP in the cancer cells normally, which acts to activate Dox.

Question 57

The amount of dietary Calories in one hard-boiled egg could raise the temperature of ________.

A)75 grams of water by 1 degree Celsius
B)750 grams of water by 1 degree Celsius
C)1,000 grams of water by 75 degrees Celsius
D)7,500 grams of water by 50 degrees Celsius

Question 58

The photos below show a plant before watering (left)and after it was watered (right). What causes the change in plant appearance?

A)Cells that were in an isotonic environment are restored to a hypotonic environment.
B)The plant wilted because its cells lysed; watering creates an isotonic environment.
C)A hypertonic solution makes the plant wilt and watering makes its cells turgid again.
D)Watering shifts a hypotonic environment to a hypertonic environment.