Ch 6 Cell interaction Quiz Questions

Which type of diffusions belong to CARRIER-MEDIATED TRANSPORT? 1. Facilitated 2. Simple diffusion 3. Osmosis 4. Active Transport 5. Diffusion of Ions through membrane CHANNELS

1. facilitated 4. Active transport

List three characteristics of facilitated diffusion that distinguishes it from simple diffusion.

1. powered by the random movement of molecules 2. requires specific carrier proteins 3. transport proteins may always exist in the plasma membrane or be insertedwhen needed.

Which types of diffusion belong to NON-CARRIER MEDIATED TRANSPORT? 1. Facilitated 2. Simple diffusion 3. Osmosis 4. Active Transport 5. Diffusion of Ions through membrane CHANNELS

2. Simple diffusion 3. Osmosis 5. Diffusion of Ions through membrane CHANNELS

Which of the following solutions is isotonic relative to blood plasma? A)0.15 m NaCl B)0.9% NaCl C)5% dextrose D)All of these are isotonic to plasma.

5% dextrose has the same osmolality as normal plasma, which is approximately 300 mOsm.

Describe the distribution of fluid in the body?

67% in the intracellular compartment 33% in the extracellular compartment ((of that 33%)) 20% - plasma membrane 80% interstitial fluid

The interstitial fluid comprises what percentage of the extracellular fluid? A)80% B)67% C)33% D)20%

A 80

Explain what is meant by simple diffusion and list the factors that influence diffusion rates

A single substance tends to move from an area of high concentration to an area of low concentration until the concentration is equal across a space. factors that effect diffusion 1. magnitude of the concentration 2. temperature 3. surface area 4. density

Living cells are negatively charged inside primarily because of ___________. A)ATP, organic acids, and other negative molecules that cannot escape B)Removal of sodium ions, which are positively charged, by the Na+/K+ pump C)Extrusion of Ca2+ ion, which is much more concentrated outside a cell than inside D)Cell membranes that are more permeable to potassium than sodium

A)ATP, organic acids, and other negative molecules that cannot escape

When the body gains water and the blood becomes too diluted, it is detected by osmoreceptors located in the ____________. A)brain B)heart C)blood vessels D)blood cells

A)brain

A deficiency of protein in the blood caused by liver disease such as cirrhosis, where the damaged liver is unable to produce adequate amounts of the protein albumin, leads to __________________. A)edema B)high blood volume C)high blood pressure D)ADH secretion

A)edema If a person has an abnormally low concentration of plasma proteins, excessive accumulation of fluid in the tissues results.

Which of the following substances is least able to diffuse through a living cellular membrane? A)glucose B)oxygen gas C)cholesterol D)water

A)glucose Oxygen gas, water, and cholesterol pass through a living cellular membrane by simple diffusion whereas glucose requires a carrier protein to diffuse.

In diabetes mellitus, the blood glucose level is high and glucose appears in the urine. This is due to a property of the carrier proteins along the kidney tubules, namely _______________. A)inhibition B)an inborn error of metabolism C)specificity D)saturation

A)inhibition

The primary effect of antidiuretic hormone (ADH) is to _____________. A)lower the osmolality of the blood B)raise the osmolality of the blood C)prevent unnecessary loss of water D)inhibit the sense of thirst

A)lower the osmolality of the blood Homeostasis of plasma concentration.

Solutes that cannot pass freely through a semipermeable membrane are said to be ______________. A)osmotically active B)osmotically inactive C)isotonic D)isosmotic

A)osmotically active Two solutions that have the same osmolality as plasma are said to be isosmotic. Two solutions that have the same concentration of non-penetrable solutes are said to be istonic. Osmotically inactive solutes can freely pass through a semipermeable membrane

Red blood cells placed in a 0.3m urea solution (urea is permeable) will exhibit _________. A)shrinkage B)no change C)crenation D)hemolysis

A)shrinkage When RBCs are placed in a 0.3m urea solution, the urea diffuses into the cells until its concentration on both sides of the cell membrane becomes equal. Meanwhile, the solutes within the cells that are osmotically active causing osmosis of water into the cells. Therefore, RBCs placed in 0.3m urea will eventually burst.

The membrane of a resting cell leaks sodium and potassium ions, but the ________ compensates for this and maintains the membrane potential near a constant value. A)sodium/potassium pump B)transport of calcium ions C)closure of potassium channels in the membrane D)closure of sodium channels in the membrane

A. A)sodium/potassium pump The sodium/potassium pump actively transports 3 Na+ out of the cell for every 2 K+ that moves into the cell.

The carrier proteins of cell membranes have many properties in common with enzymes including all of the following except ________________. A. Allosteric inhibition B)specificity C)saturation D)competition

A. Allosteric inhibition Allosteric inhibition applies to enzymes and not to carrier proteins. An allosteric inhibitor combines with a part of the enzyme at a location other than the active site to change shape so that it can no longer combine properly with its substrate.

The most important diffusible ion in the establishment of membrane potential is A. K+ B. Na+ C. Ca^2+ D. Cl -

A. K+

Two solutions are said to differ in ________ if they have different concentrations of non-penetrating solutes. A)tonicity B)molarity C)molality D)osmolality

A. TONICITY Molarity pertains to the number of moles of solute per liter of solution. Molality pertains to the number of moles of solute per kilogram of solvent. Osmolality is an expression for the total molality of a solution.

Which of these statements regarding an increase in blood osmolality is true? A. it can occur as a result of dehydration B. it causes a decrease in blood osmotic pressure C. it is accompanied by a decrease in ADH secretion D. All of these are true

A. it can occur as a result of dehydration

If a poison such as cyanide stopped the production of ATP, which of the following transport processes would cease? A. the movement of Na+ out of a cell B. Osmosis C. the movement of K+ out of the cell D. all of the above

A. the movement of Na+ out of a cell

Which of the following questions regarding second messengers is false? A. they are needed to mediate the action of nonpolar regulatory molecules B. they are released from the plasma membrane into the cytoplasm of cells C. They are produced in response to the binding of regulatory molecules to receptors in the plasma membrane D. They produce the intracellular actions of polar regulatory molecules

A. they are needed to mediate the action of nonpolar regulatory molecules

The term, potential difference, means the amount of electrical charge (voltage) that exists across a cell membrane at any moment. A)True B)False

A. true

Explain how active transport differs from facilitated diffusion.

Active transport needs energy(ATP) while facilitated diffusion does not need energy.Active transport needs energy because the substance is going against the concentration gradient.

Ion channels in a cell membrane permit the selective passage of ____________. A)respiratory gases B)Na+ and K+ C)amino acids D)small organic wastes

B)Na+ and K+ Na+ selectively passes through Na+ ion channels and K+ selectively passes through K+ ion channels.

If transport through a cell membrane requires the expenditure of energy, it is called ____________. A)facilitated diffusion B)active transport C)simple diffusion

B)active transport Both facilitated diffusion and simple diffusion are passive forms of transport that rely on concentration gradients and not the expenditure of energy.

Integrins ____________________. A)are the protein fibers of the cytoskeleton B)are glycoproteins that are found extending through the plasma membrane C)are enzymes that break down extracellular matrix proteins D)are proteins that inhibit blood clotting

B)are glycoproteins that are found extending through the plasma membrane Integrins extend from the cytoskeleton within a cell, through the cell membrane, and into the extracellular matrix. By binding to components within the matrix, they serve as a sort of "glue" or adhesion molecule between cells and the extracellular matrix.

The number of molecules diffusing through a membrane per unit time (rate) depends on all of the following except the ____________. A)concentration of molecules on each side of the membrane B)availability of ATP C)permeability of the membrane to the molecules D)surface area of the membrane

B)availability of ATP Diffusion occurs along concentration gradients and does not rely on the availability of ATP unless it's an active transport.

Water passes from the tissue fluids into the blood capillaries mainly because _________. A)blood has a lower protein concentration than the tissue fluids B)blood has a higher protein concentration than the tissue fluids C)blood contains more salt than the tissue fluids D)tissue fluids are more concentrated than the blood plasma

B)blood has a higher protein concentration than the tissue fluids Plasma proteins cannot pass from the capillaries into the tissue fluid because the plasma proteins are osmotically active.

The Nernst equation enables us to calculate the membrane voltage that exactly balances the diffusion of a particular ion down its concentration gradient. To use the equation, however, we must know all of the following, except the _____________. A)valence of the ion (for example, +1 for potassium; +2 for calcium) B)equilibrium potential of the ion in millivolts (mV) C)intracellular concentration of the ion in mEq/L D)extracellular concentration of the ion in mEq/L

B)equilibrium potential of the ion in millivolts (mV) Valence is represented by z in the equation, intracellular concentration of the ion in mEq/L is represented by [Xi], and extracellular concentration of the ion in mEq/L is represented by [Xo]. The equilibrium potential of the ion in mV is what the Nernst equation calculates.

Excessive vomiting, for example, can deplete the body's K+ reserves and abnormally lower the potassium concentration in the plasma (hypokalemia). The membrane potential of cells under the influence of hypokalemia would record a value _______________. A)somewhere between +90 and +120 mV B)somewhere between (--)65 and (--)90 mV C)somewhere between (--)40 and (--)65 mV D)around +60mV

B)somewhere between (--)65 and (--)90 mV When an abnormal decrease in the blood concentration of K+ occurs, less K+ can enter the cell. In terms of the Nernst equation, the ratio of [K+o] to [K+i] increases. This raises the membrane potential (taking it further away from zero).

Cells take in oxygen by simple diffusion and glucose by facilitated diffusion. Therefore, oxygen uptake and glucose uptake will differ from each other in all of the following respects except ________________. A)specificity B)the need for ATP C)competition by other solutes D)saturation

B)the need for ATP Neither the simple diffusion of oxygen nor the facilitated diffusion of glucose require ATP.

When a cell reaches a potassium equilibrium, __________________. A)all diffusion of K+ stops B)there are equal amounts of K+ ions on both sides of the cell membrane C)K+ outward diffusion is balanced by electrical attraction inward D)The membrane potential is about +60mV

B)there are equal amounts of K+ ions on both sides of the cell membrane

Plasma has an osmolality of about 300 mOsm. The osmolality of isotonic saline is equal to A. 150 mOsm B. 300 mOsm C. 600 mOsm D. none of the above

B. 300 mOsm

The cell membrane is more permeable to _______ than any other cation. A)Na+ B)K+ C)Ca2+ D)H+

B. K+ There are more K+ channels in the cell membrane making it more permeable to K+.

Which of these is not an example of cotransport? A. movement of glucose and Na+ through the apical epithelial membrane in the intestinal epithelium B. Movement of Na+ and K+ through the action of the Na+/K+ pumps C. movement of Na+ and glucose across the kidney tubules D. Movement of Na+ into a cell while Ca^2+ moves out

B. Movement of Na+ and K+ through the action of the Na+/K+ pumps

Which of these statements about the facilitated diffusion of glucose is true? A. there is a net movement from region of lower to the region of higher B. carrier proteins in the cell membrane are required for this transport C. This transport requires energy obtained from ATP D. It is an example of cotransport

B. carrier proteins in the cell membrane are required for this transport

Red blood cells crenate in a A. hypotonic B. hypertonic C. isotonic

B. hypertonic

Which of these statements about carrier mediated facilitated diffusion is true? A. it uses cellular ATP B. it is used for cellular uptake of blood glucose C. it is a form of active transport D. none of these are true

B. it is used for cellular uptake of blood glucose

in Hyperkalemia, the resting membrane potential A. moves farther from 0 millivolts B. moves closer to 0 millivolts c. remains unaffected

B. moves closer to 0 millivolts

The atomic weights of the following elements are C = 12, O = 16, H = 1. The formula for glucose is C6H12O6. Maltose is made by combining two glucose molecules with the removal of (--)H and (--)OH groups to form water as a by-product. Thus the molecular weight (MW) of maltose is ______________. A)58 B)180 C)342 D)360

C)342 The two molecules of glucose (each with a molecular weight of 180, therefore 180 + 180 = 360) joined by dehydration synthesis (subtract the molecular weight of H2O which = 18) forms a maltose molecule with a molecular weight = 342.

Red blood cells placed in a hypertonic solution will ________________. A)swell and eventually lyse B)remain unchanged C)crenate D)hemolysis

C)crenate

Glutamic acid weighs 147 grams per mole. To make a 1 M solution of glutamic acid, you could ____________________. A)dissolve 147 g in 1 kg (kilogram) of water B)dissolve 147 g in 1 L (liter) of water C)dissolve 147 g in enough water to make 1 L of solution D)dissolve 147 g in enough water to make 1 kg of solution

C)dissolve 147 g in enough water to make 1 L of solution One mole of solute dissolved in water to make one liter of solution is a one-molar-solution [abbreviated 1.0 M].

Avogadro's number (6.02 x 1023) refers to ___________________. A. how many moles of solute are needed to make an isotonic solution B)the freezing point depression in relation too osmolality C)how many molecules are present in one mole of a substance D)how many moles of a substance are present in one kilogram

C)how many molecules are present in one mole of a substance An amount of any compound equal to its molecular weight in grams must contain the same number of molecules as an amount of any other compound equal to its molecular weight in grams, which is 6.02 x 1023.

In biological applications, it is often preferable to measure solution concentrations in molality rather than molarity, especially if comparing solutions of two different substances. This is because ___________________. A)with molarity it is impossible to calculate whether a solution is isotonic to living tissues. B)two solutions of the same molality have equivalent ratios of solute to water, but two solutions of the same molarity may not have equivalent ratios. C)if one scientist reports concentrations measured in molality, another scientist elsewhere can exactly replicate the work. This is not possible with molarity.

C)if one scientist reports concentrations measured in molality, another scientist elsewhere can exactly replicate the work. This is not possible with molarity. Although molarity is used quite often in chemistry, it is not completely desirable in discussions of osmosis because the exact ratio of solute to water is not specified.

Primary active transport involves a conformational change in the carrier protein. The most immediate stimulus for this is ______________. A)a change in membrane voltage B)binding of the carrier protein to a molecule in the extracellular fluid C)phosphorylation (binding of the carrier protein to a phosphate group) within the cell D)fluctuations in the pH of the medium around the carrier protein

C)phosphorylation (binding of the carrier protein to a phosphate group) within the cell

Movement of water through a cell membrane, rather than a solute, is called _________. A)simple diffusion B)solvent diffusion C)osmosis

C. osmosis

The movement of water across a plasma membrane occurs by A. an active transport water pump B. a facilitated diffusion carrier C. simple diffusion through membrane channels D. all the above

C. simple diffusion through membrane channels

The resting membrane potential of neuron or muscles cells is A. Equal to the potassium equilibrium potential B. equal to the sodium equilibrium potential C. somewhat less negative than the potassium equilibrium potential D. somewhat more positive than the sodium equilibrium E. not changed by stimulation

C. somewhat less negative than the potassium equilibrium potential

Extracellular fluid contains up to 10,000 times more calcium than intracellular fluid, and yet all cells continue to pump out even more calcium. They could only do this by means of ______________. A)pinocytosis B)facilitated diffusion C)osmosis D)active transport

D)active transport Active transport uses ATP to move ions and molecules against their concentration gradients.

Some cells employ a countertransport (or antiport) mechanism to maintain a high extracellular Ca2+ concentration coupled to the passive inward diffusion of Na+. This best describes __________________. A)a membrane which is impermeable to Ca2+ and will not let it into the cell B)primary active transport of Ca2+ out of the cell C)facilitated diffusion of Ca2+ out of the cell D)secondary active transport of Ca2+ out of the cell

D)secondary active transport of Ca2+ out of the cell The uphill extrusion of Ca2+ from a cell by a type of pump that is coupled to the passive diffusion of Na+ into the cell is called secondary active transport.

Cells continually generate carbon dioxide and must get rid of it. The mechanism by which carbon dioxide moves out of the cell is by ________________. A)active transport B)facilitated diffusion C)cotransport D)simple diffusion

D)simple diffusion Small molecules that have polar covalent bonds but which are uncharged like carbon dioxide can penetrate the phospholipid bilayer by simple diffusion.

A high density of microvilli is to be expected especially on the surface of epithelial cells located in the _______________. A)brain B)liver C)muscles D)small intestine

D)small intestine The rapid diffusion of the products of digestion across the epithelial membrane in the small intestine is aided by microvilli that increase surface area.

Suppose that gated ion channels for Na+ or Ca^2+ opened in the plasma membrane of a muscle cell. The membrane potential of that cell would.. A. move toward the equilibrium potential for that ion B. become less negative than the resting membrane potential C. move farther away from the potassium equilibrium D. all of these

D. all of these

Which of these statements comparing a 0.5 m NaCL solution and a 1.0 m glucose solution is true? A. they have the same osmolality B. they have the same osmotic pressure C. they are isotonic to each other D. all of these are true

D. all of these are true

Which of these statements about the Na+/K+ pump is true? A. Na+ is actively transported into the cell B. K+ is actively transported out of the cell C. an equal number of Na+ and K+ ions are transported with each cycle of the pump D. the pumps are constantly active in all cells

D. the pumps are constantly active in all cells

Facilitated diffusion can transport molecules against a concentration gradient. A)True B)False

FALSE Facilitated diffusion is a type of passive transport using a carrier protein and does not require ATP but instead follows the concentration gradient.

The spontaneous, random diffusion of molecules creates a concentration gradient. A)True B)False

FALSE The random molecular motion tends to eliminate the concentration difference as the molecules become more diffusely spread out.

____________ is a solution in which the concentration of both the solvent and solute ate equal on both sides of the cell membrane. ___________ is a solution in which there is a higher concentration of water molecules (solvent) outside a cell than on the inside. ___________ is a solution in which there is ahigher concentration of water molecules (solvent) inside a cell than on the outside of the cell. A. Hypertonic B. Hypotonic C. Isotonic

Isotonic hypotonic hypertonic

The dialysis membranes used in the treatment of kidney disease do not allow plasma protein molecules to pass. A)True B)False

TRUE Dialysis membranes allow waste molecules to diffuse through but molecules that are needed by the body, such as plasma proteins are held back.

Simple diffusion does not require a living cell membrane. A)True B)False

TRUE As long as there is a concentration gradient, simple diffusion will occur such as Koolaid powder sprinkled on top of a container of water.

A concentration gradient is a state of low entropy. A)True B)False

TRUE Because a concentration difference represents an unstable state of high organization or low entropy.

Small, nonpolar (or uncharged) ((such as Oxygen, carbon dioxide, and steroid hormones lipid-soluble molecules)) pass easily through the lipid portion of the membrane T/F

True

The basal lamina consists of collagen and is part of the extracellular matrix. A)True B)False

True The basal lamina consists of a type of collagen that underlies epithelial membranes and by forming chemical bonds between the carbohydrates on the outside surface of cell membranes and the glycoproteins of the extracellular matrix, the basal lamina helps to wed the epithelium to its underlying connective tissue.

The Na+/K+ pumps are found only in nerve and muscle cells. A)True B)False

false Most cells of the body have numerous Na+/K+ pumps that are constantly active. For example, there are about 200 per RBC, 35,000 per WBC, and several million per kidney tubule cell.

Osmosis is the movement of water through a semipermeable membrane from the side with a more concentrated solution to the side with a more dilute solution. A)True B)False

false Osmosis is the movement of water through a semipermeable membrane from the side with a more dilute solution to the side with a more concentrated solution

Osmosis is the net diffusion of water through a semipermeable membrane, so pure water has a lower osmotic pressure than any solution. A)True B)False

false Pure water has zero osmotic pressure.

Functions of ______ 1. Impart a polarity to cells 2. Affect adhesion and motility 3. Affect proliferation

integrin

The net diffusion of water across the membrane is known as _______

osmosis

Proteins given intravenously would raise a patient's blood volume and pressure. A)True B)False

true This is because proteins are osmotically active.