BIO 156 Mastering 9 (Ch 5 Part A)

Which of these is hydrophobic like the interior of the plasma membrane? The figure shows the structure of a cell membrane. There are a lipid bilayer, the cytoplasm, and the extracellular fluid. Several molecules are placed in the extracellular fluid, and they are labeled from A to D. Lipid soluble molecule is labeled as A, water as B, glucose as C, and a hydrogen ion as D. A C B C and D D

A

Question 1: After reading Example 1, you will be ready to answer this question. Do fish drink? No, because fish keep their mouth shut. No, because the water they live in tastes bad. Although freshwater fish do not drink, saltwater fish must drink because they lose too much water through their gills.

Although freshwater fish do not drink, saltwater fish must drink because they lose too much water through their gills.

Question 5: After reading Example 5 on reverse osmosis filters, you will be ready to answer this question. Why are they called "reverse osmosis filters?" Because fancy names sell more products. Because the person who named it didn't understand osmosis. Because high pressure is used to push water through a filter, against the concentration gradient.

Because high pressure is used to push water through a filter, against the concentration gradient.

Which of the following is NOT a true statement about diffusion? Diffusion is a result of the kinetic energy of atoms and molecules. Diffusion requires no input of energy into the system. Diffusion proceeds until equilibrium is reached. Diffusion occurs when particles spread from areas of low concentration to areas of high concentration.

Diffusion occurs when particles spread from areas of low concentration to areas of high concentration.

Question 4: After reading Example 4 on food in the frig, you will be ready to answer this question. Why does jelly last so long in the frig? Toxic preservatives in jelly kill bacteria. Most companies add antibiotics to jelly. Jelly contains so much sugar that it creates a hypertonic environment, inhibiting the growth of bacteria and mold.

Jelly contains so much sugar that it creates a hypertonic environment, inhibiting the growth of bacteria and mold.

Question 2: After reading Example 2, on diarrhea and constipation, you will be ready to answer this question. Why might a salty laxative help relieve constipation? Anything that tastes that bad is bound to cause diarrhea. Salty laxatives in the large intestine help pull water out of cells and into the intestine by osmosis, thereby relieving constipation. Laxatives contains toxins, and your body tries to remove them quickly from the digestive tract.

Salty laxatives in the large intestine help pull water out of cells and into the intestine by osmosis, thereby relieving constipation.

Which statements about the fluid mosaic structure of a membrane are correct? Select the three correct statements. Membranes include a mosaic, or mix, of carbohydrates embedded in a phospholipid bilayer. The diverse proteins found in and attached to membranes perform many important functions. Because membranes are fluid, membrane proteins and phospholipids can drift about in the membrane. The framework of a membrane is a bilayer of phospholipids with their hydrophilic heads facing the aqueous environment inside and outside of the cell and their hydrophobic tails clustered in the center. The kinky tails of some proteins help keep the membrane fluid by preventing the component molecules from packing solidly together.

The diverse proteins found in and attached to membranes perform many important functions. Because membranes are fluid, membrane proteins and phospholipids can drift about in the membrane. The framework of a membrane is a bilayer of phospholipids with their hydrophilic heads facing the aqueous environment inside and outside of the cell and their hydrophobic tails clustered in the center.

Question 3: After reading "Example 3: Water, water everywhere, and not a drop to drink!" you will be ready to answer this question. Why can't we drink seawater? The salts in the saltwater cause water to be pulled out of our tissues, causing dehydration. Because whales have pooped in the water, and it is not safe to drink. There are toxins in seawater that we shouldn't drink.

The salts in the saltwater cause water to be pulled out of our tissues, causing dehydration.

If you are going to bake potatoes, and your potatoes are soft and dehydrated, they can be soaked in __________ to make them more firm before baking. an isotonic solution a hypertonic solution made with distilled water and a tablespoon of salt a hypotonic solution such as tap water a hypertonic solution such as distilled water

a hypotonic solution such as tap water

In this diagram of the plasma membranes of two adjoining cells, identify the protein indicated by the white arrow, including its function. Plasma membranes of two adjoining cells. A white arrow points to a protein that spans the membrane. The protein has a binding site on the exterior surface for a specific molecule. A dotted line with an arrow at the end extends into the cell. a glycoprotein that is involved in cell-cell recognition an active transport protein that moves molecules across a membrane against their concentration gradient a receptor protein that binds with a signaling molecule and relays the message into the cell by activating other molecules inside the cell a protein involved in enzymatic activity an attachment protein that provides structural support

a receptor protein that binds with a signaling molecule and relays the message into the cell by activating other molecules inside the cell

Which of these processes can move a solute against its concentration gradient? active transport osmosis facilitated diffusion passive transport diffusion

active transport

Which of these processes requires energy? active transport passive transport facilitated diffusion diffusion osmosis

active transport

Which of the following is a difference between active transport and facilitated diffusion? active transport requires energy from ATP and facilitated diffusion does not facilitated diffusion requires energy from ATP and active transport does not facilitated diffusion involves transport proteins and active transport does not active transport involves transport proteins and facilitated diffusion does not facilitated diffusion can move solutes against a concentration gradient

active transport requires energy from ATP and facilitated diffusion does not

The sodium-potassium pump uses energy from ATP to move sodium ions out of the cell, and potassium ions into the cell. This is an example of passive transport. facilitated diffusion. diffusion. exocytosis. active transport.

active transport.

Which of the following can move across membranes by diffusion? water oxygen carbon dioxide all of the above none of the above

all of the above

Which of the following can move across membranes by passive transport? oxygen carbon dioxide water all of the above none of the above

all of the above

Which of the following is a function of membrane proteins? some proteins function as receptors for chemical messengers from other cells some proteins are enzymes involved in catalytic reactions some proteins are involved in transport, and help move substances across the membrane some proteins are receptors involved in signal transduction all of the above

all of the above

When diffusion across a membrane stops because a state of dynamic equilibrium is reached, it means that: more molecules are moving out than in. molecules are no longer moving across the membrane. an equal number of molecules are moving in and out, so there is no net movement. more molecules are moving in than out.

an equal number of molecules are moving in and out, so there is no net movement.

A cell that neither gains nor loses water while sitting in a solution is probably sitting in a hypotonic environment. distilled water. an isotonic environment. a hypertonic environment.

an isotonic environment

What type of organism has cholesterol in it's membranes? animals fungi plants all of the above

animals

The movement of molecules from higher concentration to lower concentration is called: diffusion active transport cytoplasm orientation none of the above

diffusion

The plasma membrane forms a pocket that pinches inward, forming a vesicle that contains material from outside the cell. This describes the process of active transport. exocytosis. diffusion. passive transport. endocytosis.

endocytosis.

A white blood cell is capable of producing and releasing thousands of antibody molecules every second. Antibodies are large, complex protein molecules. How would you expect them to leave the cell? passive transport diffusion active transport exocytosis receptor-mediated endocytosis

exocytosis

If a large hormone molecule is produced inside a cell, the hormone can be released out into the extracellular environment by: exocytosis. endocytosis. osmosis. active transport. diffusion.

exocytosis

The export of macromolecules out of the cell by means of a membrane-enclosed vesicle moving to the plasma membrane is called: active transport pinocytosis exocytosis phagocytosis endocytosis

exocytosis

A molecule moves down its concentration gradient using a transport protein in the plasma membrane. This is an example of active transport. exocytosis. facilitated diffusion. diffusion. endocytosis.

facilitated diffusion.

Which of the following best describes the plasma membrane? cobblestone road covered on the outside by cytoskeleton dense rows of cellulose rigid and impermeable fluid mosaic

fluid mosaic

Paramecium is a genus of protists that lives in water. It has organelles called contractile vacuoles that continually eliminate the excess water gained through osmosis. Knowing that Paramecia gain water through osmosis, we can deduce that they normally live in the ocean. freshwater lakes and ponds. very salty environments. ice and very cold environments.

freshwater lakes and ponds

Identify Structure A. The figure shows a model of a cell membrane with the cytoplasm and extracellular fluid. Different parts of it are labeled with letters. Some big molecules embedded in lipid bilayer and bound with oligosaccharides outside the cell are marked A. Some molecules of lipid bilayer are bound with oligosaccharides outside the cell; this oligosaccharide part is marked B. Thick long filaments outside the cell are marked C. A part of the membrane which consists of 2 layers of molecules, is labeled D. Molecules which are a part of lipid bilayer and have different effects on the membrane fluidity at different temperatures are found only in animals and are marked E. Large molecules which are embedded in lipid bilayer and protrude on both sides of it are labeled F. phospholipid extracellular matrix glycoprotein protein cholesterol

glycoprotein

Which of the following function as cell identification tags that can be recognized by other cells? cellulose and amylase glycoproteins and glycolipids lysosomes and peroxisomes glycerol and fatty acids cytoplasm and cytoskeleton

glycoproteins and glycolipids

What is the role of cholesterol molecules that are embedded in the membranes of some living things? keep the membrane rigid at lower temperatures help transport large molecules across the membrane help stabilize the phospholipids at body temperature all of the above

help stabilize the phospholipids at body temperature

A plant cell placed in a(n) _________- solution will lose water and plasmolyze. hypertonic isotonic hypotonic

hypertonic

If the solution outside of a cell has a greater concentration of solutes than the solution inside the cell, the solution outside the cell is ___ in relation to the cell. hydrophilic isotonic hypertonic hydrophobic hypotonic

hypertonic

There is a net diffusion of water out of an animal cell when it is placed in a(n) _________ solution. hypertonic isotonic hypotonic

hypertonic

This cell is in a(n) _____ solution. The figure shows a cell membrane, the extracellular fluid, and the cytoplasm. The concentration of the solute is higher outside the cell. The figure shows 2 states of the cell: when it was just placed in this solute and over the time. hypotonic and isotonic hypertonic hypertonic or isotonic isotonic hypotonic

hypertonic

You know that this cell is in a(n) _____ solution because it _____. The figure shows a cell placed in a solution with a higher concentration than inside the cell. The movement of the water is directed outside the cell, and the cell is shrunken. hypertonic solution ... lost water hypertonic ... gained water hypotonic ... lysed hypotonic ... is turgid hypertonic ... lysed

hypertonic solution ... lost water

2. An animal cell placed in a(n) ________ solution will gain water, swell, and possibly burst. hypertonic isotonic hypotonic

hypotonic

If the solution outside of a cell has a lower concentration of solutes than the solution inside the cell, the solution outside the cell is ___ in relation to the cell. hypotonic hydrophobic hydrophilic isotonic hypertonic

hypotonic

In a plant cell, if there is a net inflow of water keeping pressure exerted against the inside of the cell wall, the cell must be in ___ environment. a hypotonic a hypertonic a very salty an isotonic a flaccid

hypotonic

Some protists (like Paramecium) have special organelles called ontractile vacuoles that continually eliminate excess water from the cell. The presence of these organelles tells you that the environment is ___ to the protist. hypertonic isotonic hypotonic

hypotonic

The ideal osmotic environment for a plant cell is a(n) _______ environment. hypertonic isotonic hypotonic

hypotonic

You know that this cell is in a(n) _____ solution because the cell _____. The figure shows a cell membrane, the extracellular fluid, and the cytoplasm. The concentration of the solute is higher inside the cell. The figure shows 2 states of the cell: when it was just placed in this solute and over the time. hypotonic ... shrunk hypotonic ... swelled hypertonic ... lost water hypertonic ... gained water isotonic ... neither lost nor gained water

hypotonic....swelled

Endocytosis moves materials _____ a cell via _____. into ... facilitated diffusion out of ... diffusion into ... a transport protein into ... membranous vesicles out of ... membranous vesicles

into ... membranous vesicles

A plant cell surrounded by a(n) __________ solution will be flaccid (limp). hypertonic isotonic hypotonic

isotonic

If the solutions both inside and outside of a cell have an equal concentration of solutes, the solution outside the cell is ___ in relation to the cell. hypertonic hydrophobic hypotonic isotonic hydrophilic

isotonic

The ideal osmotic environment for an animal cell is a(n) ________ environment. hypertonic isotonic hypotonic

isotonic

In a hypertonic environment, a plant cell will: become larger become younger become turgid lose the water from the central vacuole, and the cell membrane will pull away from the cell wall become active

lose the water from the central vacuole, and the cell membrane will pull away from the cell wall

A human cell placed into a hypertonic solution is likely to burst as a result of osmosis. remain unchanged. increase in size. lose water by osmosis.

lose water by osmosis

In active transport, molecules move across the plasma membrane against their concentration gradient. no energy input is required from the cell. the plasma membrane forms a pocket that pinches inward, forming a vesicle that contains material from outside the cell. a vesicle inside the cell fuses with the plasma membrane and releases its contents outside the cell. molecules move across the plasma membrane by crossing the lipid bilayer directly, rather than by using a transport protein.

molecules move across the plasma membrane against their concentration gradient.

When molecules move down their concentration gradient, they move from where they are __________ to where they are ___________ .

more concentrated to less concentrated

What type of molecules pass most easily through plasma membranes? glycoproteins because they contain proteins glycolipids because they contain lipids polar molecules because they are insoluble in lipids nonpolar molecules because they are soluble in lipids ions because they are charged molecules

nonpolar molecules because they are soluble in lipids

Which of the following requires specific transport proteins? A. diffusion of oxygen B. facilitated diffusion C. active transport D. all of the above E. only B and C

only B and C

What name is given to the process by which water crosses a selectively permeable membrane? passive transport pinocytosis diffusion phagocytosis osmosis

osmosis

If the salt concentration inside a cell is 0.9%, and the salt concentration outside a cell is 9%, in which direction will there be a net movement of water by diffusion? from the cell into the nucleus into the cell movement in and out will be equal out of the cell there will be no movement since water cannot cross the membrane by diffusion

out of the cell

Diffusion across a biological membrane is called ________ .

passive transport

Facilitated diffusion is a type of _____. active transport passive transport pinocytosis phagocytosis

passive transport

A white blood cell engulfing a bacterium is an example of _____. facilitated diffusion phagocytosis receptor-mediated endocytosis pinocytosis exocytosis

phagocytosis

Identify Structure D. The figure shows a model of a cell membrane with the cytoplasm and extracellular fluid. Different parts of it are labeled with letters. Some big molecules embedded in lipid bilayer and bound with oligosaccharides outside the cell are marked A. Some molecules of lipid bilayer are bound with oligosaccharides outside the cell; this oligosaccharide part is marked B. Thick long filaments outside the cell are marked C. A part of the membrane which consists of 2 layers of molecules, is labeled D. Molecules which are a part of lipid bilayer and have different effects on the membrane fluidity at different temperatures are found only in animals and are marked E. Large molecules which are embedded in lipid bilayer and protrude on both sides of it are labeled F. cholesterol glycoprotein extracellular matrix protein phospholipid bilayer of membrane

phospholipid bilayer of membrane

Question 1: Which type of molecule is the main component of cell membranes? proteins phospholipids starches triglycerides glucose

phospholipids

Which of the following describes a phospholipid molecule? hydrophobic head, non-polar tail hydrophilic head, polar tail polar head, hydrophilic tail polar head, hydrophobic tail non-polar head, hydrophobic tail

polar head, hydrophobic tail

Sodium ions require energy to move across a plasma membrane. The movement of sodium ions across a membrane: requires a transport protein is by passive transport is by facilitated diffusion all of the above

requires a transport protein

In an aqueous environment, phospholipids tend to organize into a bilayer because the formation of a bilayer: shields the hydrophilic tails from water. shields the hydrophilic heads from water. exposes the hydrophilic tails to water. exposes the hydrophobic heads to lipids. shields the hydrophobic tails from water.

shields the hydrophobic tails from water.

When a person is dehydrated, his or her IV fluids should be isotonic, because either a hypertonic or hypotonic IV would damage red blood cells. are not necessary, since a dehydrated person would not require IV fluids. should be hypotonic, because if dehydrated, he or she needs as much water as possible. should be hypertonic, because if dehydrated, he or she probably needs salt as well.

should be isotonic, because either a hypertonic or hypotonic IV would damage red blood cells.

Structure A is a _____. The figure shows a scheme of a facilitated diffusion. The lipid bilayer, extracellular fluid, and the cytoplasm are pictured there. There is a carrier in the membrane. Particles can be seen inside and outside the cell, but their concentration is higher outside. These particles are labeled as A. phospholipid solvent solute transport protein water molecule

solute

What does it mean if the plasma membrane exhibits selective permeability? water cannot pass through the membrane all substances can cross the membrane some substances can cross the membrane more easily than other substances water can only move through the membrane from outside to inside water can only move through the membrane from inside to outside

some substances can cross the membrane more easily than other substances

What is the function of Structure E? The figure shows a model of a cell membrane with the cytoplasm and extracellular fluid. Different parts of it are labeled with letters. Some big molecules embedded in lipid bilayer and bound with oligosaccharides outside the cell are marked A. Some molecules of lipid bilayer are bound with oligosaccharides outside the cell; this oligosaccharide part is marked B. Thick long filaments outside the cell are marked C. A part of the membrane which consists of 2 layers of molecules, is labeled D. Molecules which are a part of lipid bilayer and have different effects on the membrane fluidity at different temperatures are found only in animals and are marked E. Large molecules which are embedded in lipid bilayer and protrude on both sides of it are labeled F. structural support of the cell cell-cell communication transport across the plasma membrane detection of environmental change stabilization of the phospholipids

stabilization of the phospholipids

A human cell placed in a hypotonic environment would take up water through osmosis. lose water through osmosis. shrivel up. have no change in net water balance.

take up water through osmosis

Many bacteria and fungi have a difficult time surviving on our food if the food is very salty. The best explanation for this is that the salt in the food creates a hypertonic environment for the bacteria and fungi. that bacteria and fungi cannot survive in an isotonic environment. that the salt in the food creates a hypotonic environment for the bacteria and fungi. that bacteria and fungi cannot survive in a hypotonic environment.

that the salt in the food creates a hypertonic environment for the bacteria and fungi.

You can recognize the process of pinocytosis when _____. a receptor protein is involved the cell is engulfing extracellular fluid the cell is engulfing a large particle

the cell is engulfing extracellular fluid

Which of the following will happen to an animal cell if placed in a hypotonic environment? enzymes will be released by the cell to destroy the salt water will be pumped in by active transport the cell will become larger, and may burst the cell will become smaller and shriveled the cell's volume will not be affected

the cell will become larger, and may burst

What is osmoregulation? the use of receptors to bring in macromolecules the use of proteins for cell identification the passage of nonpolar molecules through a membrane the movement of phospholipids into a bilayer the control of water balance

the control of water balance

If a cell is in equilibrium with its environment: the volume of the cell will keep getting larger the environment is probably isotonic to the cell the environment is probably hypotonic to the cell the environment is probably hypertonic to the cell the cell is probably dead

the environment is probably isotonic to the cell

Which of the following has the greatest effect on the ability of polar molecules to pass through membranes? the glycoproteins on the exterior of the cell the protein carriers that are present in the membrane the cholesterol molecules in the membrane the cytoskeleton the type of extracellular matrix

the protein carriers that are present in the membrane

If placed in distilled water, an animal cell will burst, whereas a plant cell will not. What accounts for this difference? the relative impermeability of the plant cell membrane to water expulsion of water by the plant cell's central vacuole the relative impermeability of the plant cell wall to water the fact that plant cell cytoplasm is isotonic to distilled water the relative inelasticity and strength of the plant cell wall

the relative inelasticity and strength of the plant cell wall

You are working on a team that is designing a new drug. For this drug to work, it must enter the cytoplasm of specific target cells. Which of the following would be a factor that determines whether the molecule selectively enters the target cells? the concentration of the drug molecule that is transported in the blood the similarity of the drug molecule to other molecules that are transported into the target cells the phospholipid composition of the target cells' plasma membrane the nonpolar, hydrophobic nature of the drug molecule

the similarity of the drug molecule to other molecules that are transported into the target cells

Water crosses the plasma membrane using a process that requires energy from the cell. through cotransport. through facilitated diffusion or diffusion. through active transport. against its concentration gradient.

through facilitated diffusion or diffusion.

In facilitated diffusion, a molecule cannot cross a biological membrane unless ___ is present. a hormone an acid a transport protein energy a base

transport protein

Structure A in the figure is a(n) _____. Molecules of solute, shown in the figure, can pass through the plasma membrane due to the structure A, which is placed on the surface of the membrane. The structure A has two openings - one to the extracellular fluid, another - to the cytoplasm. enzyme antibody structural protein receptor molecule transport protein

transport protein

Structure B is a _____. The figure shows a scheme of a facilitated diffusion. The lipid bilayer, extracellular fluid, and cytoplasm are pictured there. Particles can be seen inside and outside the cell, but their concentration is higher outside. Also, there is a large molecule which pierces the membrane. This molecule is labeled as B. water molecule solvent transport protein solute phospholipid

transport protein

Facilitated diffusion across a biological membrane requires ___, and moves a substance from ___ concentration. energy; low to high transport proteins; high to low energy; high to low transport proteins; low to high

transport proteins; high to low