Chapter 5, bio
Membrane potential will affect the directional movement of A. Glucose (C6H12O6) B. Cholesterol C. Potassium (K+) D. Oxygen (O2)
C. Potassium (K+)
What initiates the sodium-potassium pump? A. Three sodium ions bind to the cytoplasmic side of the protein B. Three sodium ions are translocated out of the cell C. Phosphorylated pump has low affinity for sodium allowing sodium to leave and potassium to bind D. Two potassium ions are transported into the cell E. ATP binds to the protein which becomes phosphorylated (ADP is released)
A. Three sodium ions bind to the cytoplasmic side of the protein.
A cell that is 98% water is placed in 50% salt water. This cell will A. shrink B. swell C. shrink and then swell D. remain the same size
A
A macrophage (immune cell) consuming a bacteria is best described as phagocytosis. A. True B. False
A
In receptor- mediated endocytosis, what must (cargo) molecules bind to in the plasma membrane of the engulfing cell? A. receptor B. phospholipid C. protein coat D. ligand
A
Of the following molecules, which passes through a lipid bilayer most readily? A. carbon dioxide B. glucose C. K+ D. arginine E. RNA
A
Rank the folowing substances according to their roles of simple diffusion through an artificial phospholipid bilayer (from fastest to slowest): lactose (a diasaccharide); glucose; starch; arginine; methane (CH4); ethane (C2H6); and Na+. A. methane (CH4) > ethane (C2H6) > glucose > lactose > Na+ > arginine > starch B. Na+ > ethane (C2H6) > arginine > methane (CH4) > lactose > glucose > starch C. starch > arginine > Na+ > lactose > glucose > ethane (C2H6) > methane (CH4) D. ethane (C2H6) > methane (CH4) > arginine > lactose > Na+ > glucose > starch E. starch > Na+ > ethane (C2H6) > glucose > methane (CH4) > arginine > lactose
A
Sodium Ions (Na+) and potassium ions (K+) are pumped across the sodium-potassium pump (Na+/K+-ATPase). What type of transport is this pump? A. antiporter B. biporter C. uniporter D. symporter
A
Solution "A" has a solute concentration of 10% while solution "B" has a solvent concentration of 80%. If they are separated by a selectively permeable membrane A. the net direction of water movement will be from solution "A" to solution "B" B. the net direction of water movement will be from solution "B" to solution "A" C. there will be no net movement of water D. the system is in dynamic equilibrium to begin with
A
The lipid layer that forms the foundation of cell membranes is primarily composed of molecules called __________. A. phospholipids B. fats C. proteins D. carbohydrates
A
The plasma membrane is a thin sheet of lipid embedded with A. proteins. B. carbohydrates. C. polymers. D. nucleotides. E. sodium and potassium ions.
A
The process by which a white blood cell or an amoeba engulfs bacteria is called phagocytosis. A. True B. False
A
When oxygen leaves the alveoli in the lungs and enters the capillaries, diffusion occurs. A. True B. False
A
When placed in a solution of water, a human skin cell burst. Which of the following statements best explains why this happens? A. the inside of the cell is hypertonic to the outside B. the inside of the cell is hypotonic to the outside C. the membrane contains transporters that allow the rapid movement of ions D. the membrane contains channels that allow the rapid movement of ions E. both c and d are correct explanantions
A
Which form of endocytosis is where cells can take in dissolved solutes in extracellular fluid? A. Pinocytosis B. Receptor-mediated C. Exocytosis D. Phagocytosis
A
Which phospholipid tails make biological membranes more fluid compared to their normal state? A. Unsaturated B. Long C. Saturated D. Hydrophilic
A
A scientist performs an experiment in which they create an artificial cell with a selectively permeable membrane through which only water can pass. They inject a 5M solution of glucose into the cell and then place the cell into a beaker containing 10M glucose. What effect do you expect to observe? A. Water moves out of the cell B. Glucose moves out of the cell C. No net change in cell weight D. Water moves into the cell E. Glucose moves into the cell
A. Water moves out of the cell
Membrane proteins serve many functions. One of the functions is transportation of substances across the membrane. If a cell biologist placed cells into an environment in which a chemical has been added that blocks the function of only carrier proteins, the process that will be affected is A. active transport B. osmosis C. simple diffusion D. phagocytosis E. pinocytosis
A. active transport.
Which type of proteins is embedded in the cell membrane in both active transport and facilitated transport? A. carrier B. cytoskeletal C. structural D. targeted
A. carrier
Carrier-mediated transport of a substance down its concentration gradient is called A. facilitated diffusion. B. active transport. C. exocytosis. D. endocytosis. E. phagocytosis.
A. facilitated diffusion.
If a cell has the same concentration of dissolved molecules as its outside environment, the cell's condition is referred to as being A. isotonic. B. hypertonic. C. hypotonic. D. hydrophobic. E. hydrophilic.
A. isotonic.
What is the main component of an animal cell membrane? A. phospholipids B. polynucleotides C. aquaporins D. glycolipids E. cholesterol
A. phospholipids
Osmosis is the diffusion of water across a membrane in response to the concentration of one or more of the ______. A. solutes B. membranes C. compartments D. cells
A. solutes
Membrane fluidity is affected by A. temperature, cholesterol, types of fatty acids B. size of molecules, polarity of molecules, temperature C. types of fatty acids, waters affinity for hydrogen bonding D. hydrophilic tails, hydrophobic heads, cholesterol
A. temperature, cholesterol, types of fatty acids.
In the process of diffusion, molecules move from areas where A) their concentration is higher to areas where their concentration is lower until an equilibrium is reached B) their concentration is lower to areas where their concentration is higher until an equilibrium is reached C) their concentration is lower to areas where their concentration is higher through specific protein channels or carriers D) their concentration is higher to areas where their concentration is lower using energy from ATP
A. their concentration is higher to areas where their concentration is lower until an equilibrium is reached.
All of the following cross the membrane from hughter concentration to lower concentration by simple diffusion EXCEPT A. carbon dioxide B. glucose C. nitrogen gas D. oxygen gas
B
Following a meal glucose must move from the gut lumen where there is a high glucose concentration into the intestinal cell where there is a relatively low level of glucose. This movement is called A. passive diffusion B. facilitated diffusion C. active transport D. endocytosis E. exocytosis
B
If a cell lacks ATP, which of the following processes would cease to operate immediately? A. diffusion B. sodium/potassium pump C. facilitated diffusion D. osmosis E. tonicity
B
Let's suppose an insect, which doesn't maintain a constant body temperature, was exposed to a shift in temperature from 60 degrees F to 80 degrees F. Which of the following types of cellular changes would be the most beneficial to help this animal cope with the temperature shifts? A) increase the number of double bonds in the fatty acyl tails of phospholipids. B) increase the length of the fatty acyl tails of phospholipids C) decrease the amount of cholesterol in the membrane D) decrease the amount of carbohydrate attached to membrane proteins E) decrease the amount of carbohydrate attached to phospholipids.
B
Placing celery sticks in fresh water will make them more turgid and harder. This is because A. the celery is hypotonic to fresh water B. the celery is hypertonic to fresh water C. the celery is isotonic to fresh water D. water moves from the celery sticks into fresh water E. None of the choices are correct
B
The heads of the all phospholipid molecules found in a cell membrane face inward toward the cell contents. A. True B. False
B
What kind of solution will have fewer solutes than the opposite side of the membranes? A. isotonic B. hypotonic C. hypertonic D. none of the other choices
B
When membrane-bound receptors like HER2 bind to molecules outside of the cell, they must move through the membrane and bind to a second HER2 receptor, forming a dimer, in order for the signal to be sent inside the cell. This is possible because the cell membrane is _____. A. A semi-permeable barrier B. A fluid mosaic C. Rigid like a cell wall D. Hydrophobic E. A barrier to ions
B
Where does the energy for secondary active transport come from? A. ATP B. an electrochemical ion gradient C. sucrose D. glucose
B
Which of the following best describes the selective uptake of a specific cargo molecule into the cell through receptor binding and aggregation? A. pinocytosis B. receptor-mediated endocytosis C. autophagocytosis D. phagocytosis E. receptor-mediated exocytosis
B
Which of the following crosses membranes from higher concentration to a lower concentration through a protein, by facilitated diffusion? A. oxygen gas B. ions C. nitrogen gas D. carbon dioxide
B
Which of the following molecules add stiffness and strength to the plasma membrane? A.glycoproteins B. cholesterol C. phospholipids D. enzymatic proteins E. phosphate groups
B
Which of the following refers to materials only leaving the cell? A. diffusion B. exocytosis C. endocytosis D. pinocytosis E. phagocytosis
B
Which solution will have more water than the opposite side of the membrane? A. isotonic B. hypotonic C. hypertonic D. none of the other choices
B
While water continually orients phospholipids into a lipid bilayer, it does not fix the lipids permanently into position. Thus, the bilayer is considered to be _______. A. static B. fluid C. fluctuating D. charged
B
If you were a very thirsty cell, which process would you use to take in some nutrients secreted by one of your neighbors? A. Phagocytosis B. Pinocytosis C. Receptor-mediated endocytosis D. Exocytosis
B. Pinocytosis
If you were to replace the phosphate group of a phospholipid with a fatty acid chain, you would have A. glycerol B. a triglyceride C. cholesterol D. glycolipid
B. a triglyceride.
The movement of substances to regions of lower concentration is called A. active transport. B. diffusion. C. pinocytosis. D. pumping. E. exocytosis.
B. diffusion.
Which of the following protein classes are not found as membrane proteins? A. transport channels B. hormones C. receptors D. enzymes E. identity markers
B. hormones
Membrane proteins are not very soluble in water, because they possess long stretches of non-polar amino acids that are A. too long to interact with the water molecules. B. hydrophobic. C. are transmembranal. D. hydrophilic. E. used as transport channels.
B. hydrophobic
When the solute concentration of solution A is lower than the solute concentration of solution B, solution A is considered A. hypertonic B. hypotonic C. isotonic
B. hypotonic.
The fluid nature of the membranes is attributed to a lateral movement of A. protein channels. B. phospholipid molecules. C. antigen molecules. D. pumps such as the proton pump. E. the entire lipid bilayer.
B. phospholipid molecules.
Osmosis can only occur if water travels through the A. cell wall. B. semi-permeable membrane. C. vacuole. D. ER. E. cytoskeleton.
B. semi-permeable membrane.
A phospholipid molecule: A. Has a hydrophilic head that is repelled by water B. Has hydrophilic tails that are repelled by water C. Has a hydrophilic head that is attracted to water D. Has a hydrophobic head that is repelled by water E. Has hydrophobic tails that are attracted to water
C
Large particles can be brought into the cell by A. facilitated diffusion B. active transport C. phagocytosis D. exocytosis E. all of the above
C
Pinocytosis and phagocytosis are accomplished in a cell by the A. nucleus B. mitochondria C. cell membrane D. endoplasmic reticulum E. cell wall
C
Simple diffusion occurs when what cross membranes from a higher concentration to a lower concentration? A. polar molecules B. water C. gases D. ions
C
The primary structural component of a cell membrane is: A. A cholesterol molecule B. A protein molecule C. A phospholipid molecule D. An enzyme E. A sugar molecule attached to a protein
C
What does having a higher amount of a molecule on one side of a membrane than the opposite side create? A. fluidity B. a fluid mosaic model C. a gradient D. a pump
C
What is a form of endocytosis where the cells can take in large particles and small cells such as bacteria? A. Exocytosis B. Receptor-mediated C. Phagocytosis D. Pinocytosis
C
Where does the energy for the sodium potassium pump (Na+/K+-ATPase) come from? A. potassium (K+) B. an electrochemical gradient C. ATP D. sodium (Na+)
C
Which has proteins that have a region that does not interact with the hydrophobic region of the phospholipid bilayer? A. Integral membrane B. Only transmembrane C. Peripheral membrane D. Only lipid-anchored
C
Which is a transporter that transports two or more ion/molecules in opposite directions across the cell membranes? A. biporter B. uniporter C. antiporter D. symporter
C
Which of the following events in a biological membrane would not be energetically favorable and therefore would not occur spontaneously? A. the rotation of phospholipids B. the lateral movement of phospholipids C. the flip-flop of phospholipids to the opposite leaflet D. the rotation of membrane proteins E. lateral movement of membrane proteins
C
Which of the following movements is not an example of passive transport? A. the movement of water through Aquaporin B. the innercellular transport of molecules via channels C. the transport of NA+ and K+ via Na+/K+-ATPase D. the simple diffusion of CO2 through a phospholipid bilayer E. all of the above examples of passive transport
C
Which of the following statements best descibes the chemical composition of biological memebranes? A. Biological membranes áre bilayers of proteins with associated lipids and carbohydrates B. Biological membranes are composed of two layers: one layer of phospholipids and one layer proteins C. Biological membranes are bilayers of phospholipids with associated proteins and carbohydrates D. Biological membranes are composed of equal numbers of phospholipids and one layer of proteins E. Biological membranes are composed of lipids with proteins attached to outer surface
C
Which of the following statements is TRUE of membrane phospholipids? A. The hydrophilic head groups face the interior portion of the membrane. B. The hydrophobic tail groups face the exterior portion of the membrane. C. They spontaneously flip-flop from one side of the membrane to the other. D. They freely move laterally within the membrane. E. They rarely flip-flop across or move laterally within the membrane.
C
Which of the following would not be in a biological membrane? A. phospholipid B. cholesterol C. DNA D. proteins
C
The type of movement that is specific and requires carrier molecules and energy is A. exocytosis B. facilitated diffusion C. active transport D. endocytosis E. osmosis
C. active transport.
A research laboratory is attempting to collect the content of human red blood cells. The type of solution researchers should use to cause blood cell to lyse (burst) would be A. hyperosmotic B. isosmotic C. hypoosmotic D. osmotic
C. hypoosmotic.
If two solutions have unequal concentrations of a solute, the solution with the lower concentration is called A. isotonic. B. hypertonic. C. hypotonic. D. osmosis.
C. hypotonic.
Cholesterol functions in the plasma membrane to A. transport ions. B. serve as an energy molecule. C. maintain fluidity. D. mediate steroid action. E. maintain hypertension.
C. maintain fluidity.
The part of a membrane protein that extends through the phospholipid bilayer is primarily composed of amino acids that are A. highly polar. B. negatively charged. C. non-polar. D. positively charged. E. water soluble.
C. non-polar.
The process often referred to as "cellular eating" is A. osmosis. B. pinocytosis. C. phagocytosis. D. diffusion. E. active transport.
C. phagocytosis.
A student sitting on the back row opened a bottle of foul-smelling perfume and dabbed it on her wrists. One-by-one (beginning in the back of the room) the students began to cough due to the foul smell. This phenomena was due to A. osmosis B. molecules moving from an area of low concentration to high concentration C. an allergic reaction D. diffusion E. active transport
D
In a concentration gradient, the concentration of a molecules is what to what on each side of membrane? A. high; and high B. the same; as it is C. low; and low D. high; and low
D
In eukaryotes, which of the following is NOT a function of the plasma membrane? A. barrier for separating extracellular and intracellular environments of a cell B. cell-to-cell adhesion C. selective transport D. ATP synthesis E. cell signaling
D
Molecules such as glucose and amino acids are NOT lipid soluble and therefore A. easily pass across the cell membrane B. require active transport to cross the cell membrane C. must be converted to lipids before they can enter a cell D. combine with carrier proteins and pass across by facilitated transport E. must be engulfed by a cell using endocytosis
D
Osmosis occurs as water can cross the lipid bilayer through specialized channels for water movement called ________________. A. proteins B. transmembrane carbohydrates C. membrane pores D. aquaporins
D
The First Law of Thermodynamics simply states that A. energy is constantly being created in the universe B. disorder in the universe is continually increasing C. energy can be created but not destroyed D. energy cannot be created or destroyed, just changed from one form to another E. energy can be recycled through the universe
D
The release of insulin from pancreatic cells occurs by A. endocytosis B. pinocytosis C. phagocytosis D. exocytosis E. receptor-mediated endocytosis
D
The solute concentration inside the cells of a plant is 0.3M; outside the cells, it is 0.2M. If you assume that the solutes do not readily cross the membrane, which of the following statements best describes what will happen? A. the plant cell will lose a lot of water, and the cells will crenate B. the plant cell lose a little water, and the cells will expand C. the plants cells will take up a lot of water, and the cells will undergo osmotic lysis D. the plant cell will take up a little water, and the plasma membrane of the cell will slightly push against the cell wall E. both a and B are correct
D
What describes the movement of substances down their concentration gradients? A. Osmosis B. Active transport C. Facilitation D. Diffusion
D
What does not cross the membranes by facilitated diffusion? A. calcium ions B. glucose C. proteins D. small, uncharged (hydrophobic) molecules
D
What kind of solution will have more solutes than the opposite side of the membrane? A. none of the other choices B. hypotonic C. isotonic D. hypertonic
D
Which is a transporter that transports two or more ions/molecules in one direction across the membranes? A. uniporter B. biporter C. antiporter D. symporter
D
Which of the following would be in a biological membrane? A. water B. DNA C. RNA D. carbohydrates
D
Which type of membrane protein will be used to bind to hormones? A. channel proteins B. carrier proteins C. cell recognition proteins D. receptor proteins E. enzymatic proteins
D
If ATP production is blocked, decreased transport of material across a membrane occurs. Which type of transport is affected? Choose all that apply. A) Osmosis B) Diffusion C) Facilitated Diffusion D) Active Transport E) Endocytosis
D) Active Transport E) Endocytosis
During neuronal signaling, a change in membrane potential will cause sodium channels to open and let Na+ ions diffuse down their concentration gradient into the cell. Which of the following helps establish the concentration gradient necessary for this process to occur? A. Na+/K+ channel B. voltage-gated Na+ channel C. Na+ symporter D. Na+/K+ pump
D. Na+/K+ pump
A scientist performs an experiment in which they create an artificial cell with a selectively permeable membrane through which only water can pass. They inject a 5M solution of glucose into the cell and then place the cell into a beaker of water. After an hour, what effect do you expect to observe? A. Water moves out of the cell B. Glucose moves out of the cell C. No net change in cell weight D. Water moves into the cell E. Glucose moves into the cell
D. Water moves into the cell
A type of transport of a solute across a membrane, up its concentration gradient, using protein carriers driven by the expenditure of chemical energy is known as A. osmosis. B. diffusion. C. facilitated transport. D. active transport. E. exocytosis.
D. active transport.
On the outer surface of the plasma membrane there are marker molecules that identify the cell type. Often these molecules are A. ATP. B. amino acids. C. nucleotides. D. carbohydrate chains. E. inorganic ions.
D. carbohydrate chains.
The accumulation of amino acids and sugars in animal cells can occur through A. ATP pumps. B. sodium-potassium pumps. C. glucose pumps. D. coupled transport. E. proton pumps.
D. coupled transport.
Red blood cells are bi-concave. Their shape is determined by interior proteins anchored to the membrane termed A. clathrins. B. phospholipids. C. cytoskeleton. D. spectrins. E. actin filaments.
D. spectrins.
A cell containing 2% dissolved materials is placed in a solution consisting of 4% solute. The net movement of ____ molecules will be ____ the cell due to osmosis. A. solute, into B. solute, out of C. water into D. water, out of
D. water, out of
Phospholipids and ________ are the major components of cell membranes. A. glycolipids B. cholesterol C. glucose transporters D. glycocalyx E. proteins
E
Researchers have identified a drug that prevents coat proteins in a eukaryotic cells from binding to each other. If you added the drug to a sample of cells, which of the following steps in receptor- mediated endocytosis and exocytosis would be inhibited? A. the formation of vesicles at the plasma membrane during receptor-mediated endocytosis B. the uncoating of vesicles during receptor-mediated endocytosis C. fusion between a vesicle and a lysosome during receptor-mediated endocytosis D. the formation of vesicles at the Golgi membrane during exocytosis E. both b and d are correct
E
Researchers prepared membrane vesicles with or without an H+/glucose symporter or an H+ pump out of the vesicle. If the researchers then added glucose outside the vesicles, under which of the following set of conditions would you expect glucose to move against a gradient and accumulate inside the vesicles? A. vesicles contain H+/glucose symporter, and the pH inside is lower than outside B. vesicles contain H+/glucose symporter, and the outside is lower than inside C. vesicles contain H+/glucose symporter, and the Na+ concentration inside is lower than outside D. vesicles contain H+/glucose symporter, and an H+ pump E. both b and d are correct
E
What features of a membrane are major contributors to its selective permeability? A. phospholipid bilayers B. channels and transporters C. glycoproteins on the outer surface of the membrane D. peripheral membrane proteins E. both a and b
E
When a substance moves from an area of low concentration to an area of high concentration while using energy, the process is termed A. diffusion B. osmosis C. facilitated diffusion D. pinocytosis E. active transport
E
When an atom or molecule gains one or more electrons, it is said to be A. energized B. oxidized. C. polarized D. activated E. reduced
E
When you cut into most active plant tissue, water appears almost immediately because plant cells contain a. a hypertonic solution that produces turgor pressure. b. a hypotonic solution that produces turgor pressure. c. an isotonic condition and you cut the cell open. d. a hypertonic condition and cutting it reversed this to hypotonic. e. a hypotonic condition and cutting it reversed this to hypertonic.
b. a hypotonic solution that produces turgor pressure.
Of the following conditions, which is absolutely necessary for diffusion to take place? a. a differentially permeable membrane b. low temperatures c. a concentration difference d. a non-permeable membrane e. a living cell
c. a concentration difference
Which components of a cell membrane are used for cell-to-cell recognition? a. phospholipids b. channel proteins c. glycolipids d. glycoproteins e. cholesterol molecules
d. glycoproteins