Cell Transport

A salt water fish is placed in fresh water. What is the best question a researcher might ask to determine what adaptation the fish might need to help maintain homeostasis in the new environment? answer choices a. Can the fish remove extra water which enters its cells through osmosis? b. Can the fish replenish water which leaves its cells through osmosis? c. Can the fish breathe in water with a different dissolved oxygen content? d. Can the fish metabolize food in water with a different pH?

a. Can the fish remove extra water which enters its cells through osmosis?

A cell with a 10% salt solution is placed into a beaker with a 40% salt solution. How will water move? answer choices a. It will leave the cell b. It will enter the cell c. It will move in and out equally d. There will be no movement

a. It will leave the cell

A cell with a 5% salt solution is placed into a beaker with a 10% salt solution. What will happen to the cell? answer choices a. It will shrink b. It will swell c. No change d. It will burst

a. It will shrink

Why does active transport require the use of energy by the cell? answer choices a. Molecules are being moved against the concentration gradient b. Molecules are being moved freely through the pores in the membrane. c. Active transport is a process of speeding up osmosis. d. Molecules are being moved with the concentration gradient.

a. Molecules are being moved against the concentration gradient

A student was conducting an investigation with paramecium in distilled water. The paramecium was able to maintain homeostasis even though this environment put them under stress. Which of the possible hypotheses below most likely explains how the paramecium were able to maintain homeostasis? answer choices a. The paramecium removes the extra water it absorbed b. The paramecium absorbed extra water to replace what it lost. c. The paramecium absorbed extra salt to change its concentration d. The paramecium shrank so it required less water.

a. The paramecium removes the extra water it absorbed

The concentration of glucose in solution A is 5%, and the concentration of glucose in solution B is 15%. Which statement correctly describes the movement of water between the two solutions? answer choices a. Water will diffuse from solution A to solution B. b. Water will diffuse from solution B to solution A. c. There will be diffusion of sugar from solution A to solution B. d. There will be diffusion of sugar from solution B to solution A.

a. Water will diffuse from solution A to solution B.

Osmosis occurs when there is a different concentration of solute molecules on each side of the membrane. The drawing below shows a beaker containing a 30% salt solution and a suspended cell containing a 10% salt solution. answer choices a. Water will move from the cell into the beaker, resulting in a smaller cell b. Water will move from the beaker into the cell, resulting in a larger cell. c. Salt will move from the cell into the beaker, resulting in a smaller cell. d. Salt will move from the beaker into the cell, resulting in a larger cell.

a. Water will move from the cell into the beaker, resulting in a smaller cell

Which statement best explains what happens when a cell is placed in a sugar solution with a sugar concentration that is lower than that of the cytoplasm of the cell? answer choices a. Water will move into the cell by osmosis. b. Water will move out of the cell by osmosis. c. Sugar molecules will move into the cell by osmosis. d. Sugar molecules will move out of the cell by osmosis.

a. Water will move into the cell by osmosis.

When Streptococcus pneumoniae are exposed to an antibiotic, the bacteria try to pump the antibiotic out of their cells. Which of the following mechanisms is most likely used by the Streptococcus pneumoniae to pump the antibiotic out of their cells? answer choices a. active transport b. diffusion c. facilitated diffusion d. osmosis

a. active transport

Carrot sticks that are left in a dish of freshwater for several hours become stiff and hard. Similar sticks left in a saltwater solution become limp and soft. From this we can deduce that the freshwater is ______ and the saltwater is ________ to the cells of the carrot sticks. answer choices a. hypotonic, hypertonic b. hypotonic, hypotonic c. hypertonic, hypertonic d. hypertonic, hypertonic

a. hypotonic, hypertonic

What is the primary function of carbohydrates attached to the exterior of cell membranes? answer choices a. identification of the cell b. flexibility of the membrane c. strengthening the membrane d. channels through membrane

a. identification of the cell

The phospholipid bilayer of the plasma membrane is least permeable to which substance? answer choices a. starch molecules, due to their size b. oxygen molecules, due to their solubility c. cholesterol molecules, due to their polarity d. carbon dioxide molecules, due to their charge

a. starch molecules, due to their size

An individual walks out of his air-conditioned (75°F) home into the hot outside environment (85°F). His ability to adjust to this changing environment involves a mechanism similar to answer choices a. the regulation of water loss by guard cells in plant leaves b. the digestion of carbohydrates by enzymes c. using ATP for the diffusion of water d. glucose production in the pancreas

a. the regulation of water loss by guard cells in plant leaves

What helps the cell get rid of the waste material? answer choices a. utilization of ATP molecules b. dilution of a part of the cytoplasm c. shrinking of the plasma membrane d. absorbing heat from the environment

a. utilization of ATP molecules

Which would be the best evidence that a cell is using active transport to move a substance across its cell membrane? answer choices a. Substances are moving rapidly across the cell membrane b. ATP is being rapidly consumed near the cellular membrane. c. Substances are moving from high to low concentrations d. Substances are moving through channels in the cell membrane.

b. ATP is being rapidly consumed near the cellular membrane.

According to the diagram, which statement best describes the general direction of diffusion across the membrane of this cell? This cell membrane is permeable to all materials.. answer choices a. Oxygen would diffuse into the cell. b. Carbon dioxide would diffuse out of the cell. c. Glucose would diffuse into the cell d. Protein would diffuse out of the cell.

b. Carbon dioxide would diffuse out of the cell.

Carbon dioxide and oxygen can move freely across a plasma membrane. What determines the direction that carbon dioxide and oxygen move? answer choices a. Orientation of cholesterol in the plasma membrane. b. Concentration gradient across the plasma membrane. c. Configuration of phospholipids in the plasma membrane. d. Location of receptors on the surface of the cell membrane.

b. Concentration gradient across the plasma membrane.

Cholesterol does not dissolve in blood and other water-based body fluids. To be transported through the body, it must be encased in lipoproteins, macromolecules that are water soluble. How can a cell take in lipoproteins from its extracellular fluid? answer choices a. Exocytosis. b. Endocytosis. c. Molecular pump. d. Facilitated diffusion.

b. Endocytosis.

A cell that is 80% water and 20% solute is placed in a solution that is 60% water and 40% solute. Which of the following is correct? answer choices a. It is isotonic because the concentration is the same inside and outside the cell. b. It is hypertonic because water is exiting the cell. c. It is hypotonic because water is entering the cell. d. It is hypertonic because water is entering the cell.

b. It is hypertonic because water is exiting the cell.

The image shows three samples of red blood cells placed in different solutions. Sample Q shows the cells in their normal blood plasma solution. Which statement must be true about the cells? answer choices a. Sample P was placed in a concentrated salt water solution, and sample S was placed in a concentrated sugar solution. b. Sample P was placed in a concentrated salt water solution, and sample S was placed in distilled water c. Sample S was placed in a concentrated salt water solution, and sample P was placed in distilled water d. Sample S was placed in a concentrated salt solution, and sample P was placed in a concentrated sugar solution.

b. Sample P was placed in a concentrated salt water solution, and sample S was placed in distilled water

A sodium potassium pump within a cell membrane requires energy to move sodium and potassium ions into or out of a cell. The movement of glucose into or out of a cell does not require energy. Which statement best describes the movement of these materials across a cell membrane? answer choices a. Sodium and potassium ions move by active transport and glucose moves by osmosis. b. Sodium and potassium ions move by active transport and glucose moves by facilitated diffusion. c. Sodium and potassium ions by facilitated diffusion and glucose moves by osmosis. d. Sodium and potassium ions move by facilitated diffusion and glucose moves by active transport.

b. Sodium and potassium ions move by active transport and glucose moves by facilitated diffusion.

A dinoflagellate is a photosynthetic, unicellular organism found in marine environments. What would be the effect on this organism if it was transferred from its saltwater environment to freshwater? answer choices a. The organism would lose salt through active transport. b. The organism would gain water through osmosis. c. The organism would lose water through osmosis. d. The organism would gain salt through diffusion.

b. The organism would gain water through osmosis.

Placing wilted cabbage in cold water will make it crisp again. Which statement best describes what happens to restore the cabbage to its original condition? answer choices a. Water left the cabbage cells by diffusion b. Water entered the cells of the cabbage by osmosis c. Osmosis caused salts to enter the cabbage cells. d. Salts in the cabbage leaf caused water to leave the cells.

b. Water entered the cells of the cabbage by osmosis

Cholesterol does not dissolve in blood and other water-based body fluids. To be transported throughout the body, it must be encased in lipoproteins, macromolecules that are water-soluble. How can a cell take in lipoproteins from its extracellular fluid? answer choices a. exocytosis b. endocytosis c. molecular pump d. facilitated diffusion

b. endocytosis

The diagram shows two types of blood cells, normal blood cells and blood cells after they have been placed in an unknown solution. Into what type of solution were the cells placed? answer choices a. hypotonic b. hypertonic c. isotonic d. osmotic

b. hypertonic

A cell that is 90% water and 10% solute is placed in a solution that is 90% water and 10% solute. Which of the following is correct? answer choices a. it is hypertonic because water is exiting the cell. b. it is isotonic because the concentration is the same inside and outside the cell. c. it is hypotonic because water is entering the cell. d. it is hypertonic because water is entering the cell.

b. it is isotonic because the concentration is the same inside and outside the cell.

The diagram above represents two cells viewed using the same magnification with the same microscope. One possible conclusion that can be drawn about the activity of these two cells is that answer choices a. more active transport occurs in cell B than in cell A b. more active transport occurs in cell A than in cell B c. cell B uses some of the extra mitochondria to make food d. cell A is a plant cell since it has a cell wall

b. more active transport occurs in cell A than in cell B

Why do cells need buffering agents? answer choices a. to maintain constant internal environment at a pH of 10 b. to minimize the changes in pH of the internal environment c. to function properly in an extremely basic internal environment d. to function properly in an extremely acid internal environment

b. to minimize the changes in pH of the internal environment

A person with swollen gums rinses his mouth with warm salt water, and the swelling decreases. Which has occurred? answer choices a. The swollen gums have absorbed the saltwater solution b. The saltwater solution lowers the temperature of the water in the gums c. The salt in the solution has moved against the concentration gradient d. The water in the gums has moved from a high to a low concentration of water.

d. The water in the gums has moved from a high to a low concentration of water.

A person with swollen gums rinses his mouth with warm salt water, and the swelling decreases. Which of the following has occurred? answer choices a. The swollen gums have absorbed the saltwater solution. b. The saltwater solution lowers the temperature of the water in the gums. c. The salt in the solution has moved against the concentration gradient. d. The water in the gums has moved out due to the high concentration of salt in the solution.

d. The water in the gums has moved out due to the high concentration of salt in the solution.

In an emergency trauma room, a doctor accidentally gives a patient a large transfusion of distilled water directly into one of his veins instead of blood. Predict what might happen if distilled water was given to the patient instead of blood. a. have no unfavorable effect as long as the water was sterile b. have serious, perhaps fatal effects because there would be too much fluid for the heart to pump. c. have serious, perhaps fatal effects because the red blood cells would tend to shrivel. d. have serious, perhaps fatal effects because the red blood cells would tend to burst.

d. have serious, perhaps fatal effects because the red blood cells would tend to burst.

What form of transport is illustrated in the diagram? answer choices a. active transport, moving solutes into the cell against the concentration gradient b. active transport, moving solutes into the cell down the concentration gradient c. passive transport, moving solutes into the cell against the concentration gradient d. passive transport, moving solutes into the cell down the concentration gradient

d. passive transport, moving solutes into the cell down the concentration gradient

Which is an example of osmosis? answer choices a. potassium ions moving in and out of an animal cell b. carbon dioxide moving into the leaf cells of a plant c. oxygen moving into the bloodstream from the lungs d. water moving into the root cells of a plant

d. water moving into the root cells of a plant

The diagram shows how a plant cell transports sucrose, a sugar (the plant cell wall is not shown). The proton pump (bottom) transports hydrogen ions outside the cell. The transport protein (top) allows hydrogen ions to move into the cell, but it must move a sucrose molecule along with each ion. Which statement best describes the transport of sucrose across the plasma membrane of the plant cell? answer choices a. Active transport of sucrose provides the energy to transport hydrogen ions. b. Facilitated transport of sucrose provides the energy to transport hydrogen ions. c. Active transport of hydrogen ions creates a concentration gradient of sucrose. d. Facilitated transport of hydrogen ions creates a concentration gradient of sucrose.

c. Active transport of hydrogen ions creates a concentration gradient of sucrose.

Epithelial cells have a large number of aquaporins compared to other cell types. Aquaporins are protein channels that allow water, but not other molecules, across the plasma membrane. Aquaporins aid in the transport processes of osmosis and facilitated diffusion. Which of the choices is a similarity shared by osmosis and facilitated diffusion? answer choices a. Both are forms of active transport. b. Both move water from low concentration to high concentration. c. Both move water from high concentration to low concentration. d. ATP is required by both processes.

c. Both move water from high concentration to low concentration.

A cell that is 70% water and 30% solute is placed in a solution that is 75% water and 25% solute. Which of the following is correct? answer choices a. It is isotonic because the concentration is the same inside and outside the cell. b. It is hypertonic because water is exiting the cell. c. It is hypotonic because water is entering the cell. d. It is hypertonic because water is entering the cell.

c. It is hypotonic because water is entering the cell.

Myoglobin and hemoglobin are two proteins that bind to oxygen. Hemoglobin is present in red blood cells. Myoglobin, a similar protein, is present in muscle cells. The amount of oxygen dissolved in body fluids is measured as partial pressure. The graph above shows the percent of each protein that is bound to oxygen at different partial pressures. How does the binding of oxygen by myoglobin affect oxygen homeostasis? answer choices a. It reduces the amount of oxygen in the cells of body tissues. b. It increases the amount of oxygen in the alveoli of the lungs. c. It reduces the amount of oxygen in the blood returning to the lungs. d. It increases the amount of oxygen in the blood leaving the body tissues.

c. It reduces the amount of oxygen in the blood returning to the lungs.

A pipe carries rainwater into a lake. The rainwater has picked up dissolved nitrates from surrounding lawns. Which of the following is a consequence of simple diffusion of nitrates in the lake? answer choices a. A concentration gradient of nitrates is created and maintained. b. The total amount of dissolved nitrate in the lake water decreases. c. Nitrate concentration decreases in some places and increases in others. d. Energy is required to move the nitrates from one end of the lake to the other.

c. Nitrate concentration decreases in some places and increases in others.

The calcium ion passes easily through the membrane of one cell but cannot cross the membrane of a second cell. Which part of the plasma membrane allows this substance to cross? answer choices a. Carbohydrate groups on the membrane allow ions to cross. b. The fatty acid tails of the phospholipids allow ions to cross. c. Protein channels in the plasma membrane allow ions to cross. d. Phosphate groups of the phospholipid bilayer allow ions to cross.

c. Protein channels in the plasma membrane allow ions to cross.

Which situation will most likely result in a substance diffusing into a cell? answer choices a. The pH of the substance is different from the pH of the cell. b. The cell is a plant cell and possesses a cell wall and a plasma membrane. c. The concentration of the substance is greater inside the cell than outside. d. The substance is a mixture of large organic molecules.

c. The concentration of the substance is greater inside the cell than outside.

A beaker is divided into two halves, A & B, by a membrane that is freely permeable to the water and NaCl but not to protein. Side A is half-filled with a solution of 8% protein, while side B is half filled with a 2% protein solution. Predict what would happen to side A after a few hours. a. The number of protein molecules has increased. b. The number of water molecules has decreased. c. The number of water molecules has increased. d. The percentage of water has decreased.

c. The number of water molecules has increased.

You are conducting osmosis experiments with a test tube of human cells in solution. You pour table salt into the test tube. According to the principles of osmosis, what can you predict will happen to the cells? answer choices a. They will swell and burst b. They will not be affected. c. They will shrink and shrivel. d. They will undergo rapid mitosis.

c. They will shrink and shrivel.

A freshwater plant is placed in a container of saltwater. What will most likely happen to the cells of the plant? answer choices a. They will swell because water will move into them b. They will swell because salt will move into them. c. They will shrink because water will move out of them. d. They will shrink because salt will move out of them

c. They will shrink because water will move out of them.

An osmosis investigation was conducted using chicken eggs to represent cells with semi permeable membranes. The mass of each egg was measured to determine how much water diffused into or out of the eggs. The eggs was first soaked in vinegar to dissolve the shell. Each egg was the placed in one of three different solutions for 24 hours. The table below shows the results of the investigation. Based on this experiment, which of the following should be inferred about cells with semi permeable membranes? A. Substances other than water may also cross the cell membrane. b. Substances other than water may block pores in the cell membrane. c. Water enters the cell when placed in environments of high water concentration. d. Water leaves the cell when placed in environment with a low concentration of solutes.

c. Water enters the cell when placed in environments of high water concentration.

The organism shown in the diagram normally lives in small ponds and streams that contain water with small amounts of salts and other ions. What would happen to the organism if it was moved to an environment containing distilled (pure--no salt) water? answer choices a. Salt ions would move out of the organism due to osmosis. b. Salt ions would move into the organism due to osmosis. c. Water molecules would move into the organism due to osmosis. d. Water molecules would move out of the organism due to osmosis.

c. Water molecules would move into the organism due to osmosis.

Using a microscope and a wet-mount slide, a student observed a pond water sample containing paramecia, which are single-celled freshwater organisms. He noticed that there was a structure within each living paramecium that contracted regularly—about four times each minute. He researched the organism in his science textbook and found that the structure was a contractile vacuole and its function was to remove excess water from the paramecium. In the diagram below, a paramecium is represented as seen through a microscope. The function of the contractile vacuole is described. He decided to determine if the concentration of salt in the environment of the paramecium would affect the rate at which the contractile vacuole would contract. The process used to remove excess water from the paramecium by the contractile vacuole is answer choices a. synthesis b. digestion c. active transport d. passive transport

c. active transport

How does the sodium-potassium pump make the interior of the cell negatively charged? answer choices a. by expelling anions b. by pulling in anions c. by expelling more sodium cations than potassium cations are taken in d. by taking in and expelling an equal number of cations

c. by expelling more sodium cations than potassium cations are taken in

The diagram below represents a cell and some molecules in its environment. Which molecule would require the use of energy in order to be brought into the cell? answer choices a. 1 b. 2 c. 3 d. 4

d. 4

A student filled a dialysis tube with 97% water solution and sealed the ends. The tube and its contents had a mass of 55 grams. The student placed the tube in a solution, and the mass of the tube and its contents increased to 60 grams. Into which solution was the dialysis tube placed? answer choices a. 0% water b. 95% water c. 97% water d. 99% water

d. 99% water

Which of the following does not occur due to passive transport? answer choices a. A substance moves to an area of lower concentration. b. The concentration of a solution approaches equilibrium. c. The volume of a solution changes due to the movement of water. d. A concentration gradient of a dissolved substance in a solution is created.

d. A concentration gradient of a dissolved substance in a solution is created.

Which example represents active transport? answer choices a. Carbon dioxide moves out of body cells into the blood. b. Red blood cells swell when placed in distilled water. c. A de-shelled egg shrinks when placed in a salt solution. d. An amoeba surrounds and engulfs a bacterium using pseudopodia.

d. An amoeba surrounds and engulfs a bacterium using pseudopodia.

The student predicted that the contractile vacuole would contract fewer times in one minute in a solution that had a higher concentration of salt than that found in typical pond water. This prediction is most likely answer choices a. Correct, because a high concentration of salt in the environment will force water into the cell, causing the contractile vacuole to pump b. Incorrect, because salt would be entering the cell, and the contractile vacuole would have to pump it out c. Incorrect, because the concentration of salt in the environment should not affect a cell d. Correct, because water would be moving out of the cell into the salt solution

d. Correct, because water would be moving out of the cell into the salt solution

A cell with a 20% salt solution is placed into a beaker of pure water. What will happen to the cell? answer choices a. It will shrink b. Plasmolysis c. No change d. It will burst

d. It will burst

Which is not an example of passive transport? answer choices a. Carbon dioxide in a capillary crosses the alveoli membranes of the lungs. b. Oxygen dissolved in the blood crosses the phospholipid portion of the membrane of a red blood cell. c. Glucose molecules are transported by a carrier protein until its concentration on both sides of the membrane is equal. d. Sodium ions move through a protein channel until there is a higher concentration in extracellular fluid than the cytoplasm.

d. Sodium ions move through a protein channel until there is a higher concentration in extracellular fluid than the cytoplasm.

Which statement is best supported by the diagram? answer choices a. Oxygen molecules entered the cell over time by active transport. b. Water molecules are too large to enter or leave the cell, so they remained where they were at the start of the investigation. c. Protein molecules are kept inside of the cell because the cell needs them. d. The protein molecules are too large to diffuse out of the cell.

d. The protein molecules are too large to diffuse out of the cell.