BIO 113 - Chapter 3, Part 2 Study Set

Simple and facilitated diffusion differ because __________.

facilitated diffusion requires the presence of a transport protein within the plasma membrane, while simple diffusion does not

A high concentration of water has _____ dissolved particles than a low water concentration.

fewer

Fluid and small dissolved solutes leave the pores of a capillary via the process of

filtration

The __________ determines if glucose moves into or out of the hepatocyte.

glucose concentration between the intracellular and extracellular fluid

Some individuals have defective genes for LDL receptors rendering them nonfunctional. Individuals with these mutations typically have __________.

higher than normal blood cholesterol levels due to inability of peripheral cells to uptake LDLs

A solution that contains a higher concentration of solutes than the cytosol of a cell would be considered _____ in reference to the cell.

hypertonic

Up to a point, _____ solute concentration increases transport rate.

increasing

An individual displaying a larger than normal number of LDL receptors is __________ likely to develop artherosclerosis.

less

The directional movement of ions by facilitated diffusion through protein channels is determined by __________.

the electrochemical gradient of the ion being transported

A red blood cell placed in a hypertonic medium will __________.

Shrink

During one cycle, the sodium-potassium pump binds and moves __________.

3 Na+ and 2 K+

Which membrane transport process consumes ATP and uses a carrier?

Active

What do facilitated diffusion and primary active transport have in common?

Both are examples of carrier-mediated transport

What is the source of energy used to power the sodium-potassium pump?

Breakdown of ATP

Which one of the following molecules is able to move across the cell membrane by simple diffusion? Hemoglobin Glucose DNA Starch Carbon dioxide

Carbon dioxide

What does facilitated diffusion require?

Carrier proteins

Water you drink is absorbed into the blood from the digestive tract. An increase in water intake causes a(n) __________ in the plasma osmolarity.

Decrease

Examples of passive membrane transport

Diffusion Filtration Osmosis Movement of molecules from an area of higher concentration to an area of lower concentration Movement down a concentration gradient

Cellular products such as hormones and neurotransmitters are released by the process of __________.

Exocytosis

Neurons release neurotransmitters using secretory vesicles which form in the cell and empty their contents into the interstitial fluid. What type of cellular transport is occurring?

Exocytosis

Release of the digest bacterium indicates the excretion waste products via _____

Exocytosis

What is the fluid located between cells called?

Extracellular or interstitial fluid

Sugars and amino acids are carried into most body cells by means of

Facilitated diffusion

T/F The sodium-potassium pump maintains a high sodium ion concentration in the cell.

False

T/F Unlike simple diffusion, facilitated diffusion requires energy expenditure by the cell

False

Some large, polar molecules, which can cross the membrane via facilitated diffusion.

Glucose

The movement of water by osmosis is always from a __________.

High to low water concentration

A cell placed into which solution will lose water by osmosis?

Hypertonic

Physiological saline is a solution containing 0.9% NaCl. A cell in 1.5% NaCl is in a(n) __________ solution.

Hypertonic

An IV solution of 0.45% NaCl is __________ and induces the movement of water __________.

Hypotonic; into cell

Facilitated diffusion occurs __________.

In either direction depending on the concentration gradient of the molecule

When a cell is in a solution where the concentration of solute is the same in the cell as in the solution, the solution is called ________.

Isotonic

Examples of impermeable substances

Large polar molecules Ions Proteins Phosphates

The Na+/K+ ATPase moves sodium in the __________ direction compared with the direction it travels through sodium leakage channels.

Opposite

The movement of water across a semi-permeable membrane is called

Osmosis

What is the diffusion of water down its own concentration gradient through a selectively permeable membrane called?

Osmosis

Small, non polar molecules, which can pass directly through the phospholipid layer

Oxygen

White blood cells engulf bacteria by means of __________.

Phagocytosis

What brings nonspecific material into a cell?

Pinocytosis

Examples of active membrane transport

Pinocytosis Vesicular transport Sodium-potassium pumps Movement up a concentration gradient Receptor-mediated transport

Examples which would cause hemolysis

Placing a red blood cell in distilled water Placing a red blood cell with an ICF concentration of 0.9% NaCl into a solution with 0.1% NaCl Placing red blood cell into a hypotonic solution

Examples which would cause crenation

Placing a red blood cell into a hypertonic solution Placing a red blood cell with a concentration 0.9% NaCl into a solution of 1.5% NaCl

Water diffuses through certain organs such as the kidneys and bladder much faster than would occur by passive diffusion through a lipid bilayer alone. What accounts for this more rapid rate of water transport in these organs?

Presence of aquaporin channels for facilitated diffusion of water

The concentration of calcium in a cell is 3%. The concentration of calcium in the surrounding fluid is 1%. How could the cell obtain more calcium?

Primary active transport

Which of the following is the type of transport that LDL (low-density lipoprotein) uses to enter a cell?

Receptor-mediated endocytosis

Exocytosis is a process by which cells _____

Release substances from the cell via vesicles

SGLTs rely on a method of membrane transport called _____ to simultaneously move glucose and sodium across the cell membrane.

Secondary active transport

What method of membrane transport requires ATP, but only indirectly?

Secondary active transport

Which will pass through a cell membrane most easily?

Small non polar molecules

Examples of permeable substances

Small polar molecules Urea Oxygen molecules Carbon dioxide

Charged particles, which can diffuse through the membrane if specific channel proteins are open.

Sodium ions

What is responsible for maintaining the ionic gradients required for nerve impulse conduction?

Sodium-potassium pump

Sugars can be transported into cells against their concentration gradient because of __________.

Symport with sodium ions

When sugar is mixed with water, equilibrium is reached when __________.

The dissolved sugar molecules are evenly distributed throughout the solution

Which is the most direct source of energy for cotransport?

The movement of one of the transported substances down its concentration gradient

Why do patients with cystic fibrosis have thick, sticky mucus in their lungs?

Their lungs have faulty chloride pumps.

The ability of a solution to affect the fluid volume in a cell is referred to as its ______.

Tonicity

This point is referred to as the _____ maximum.

Transport

T/F A 5% urea solution is hypotonic to a 10% urea solution.

True

T/F Both symport and antiport require transport proteins.

True

T/F Diffusion is one of the processes in which materials are exchanged between a cell and its environment.

True

T/F Facilitated diffusion requires a specific transporter for a specific molecule.

True

T/F If a cell is placed in an isotonic medium, there will be no net movement of water.

True

T/F If the material the cell takes in is liquid, the process is termed pinocytosis.

True

T/F Low-density lipoprotein is brought into the cell by receptor-mediated endocytosis.

True

T/F The binding and release of sodium or potassium ions are due to conformational changes in the protein.

True

T/F The sodium-potassium pump is a transmembrane protein.

True

Which type of membrane transport moves large particles and fluid droplets across the cell membrane?

Vesicular transport

Small, polar molecules, which can slip through small gaps in the phospholipid bilayer.

Water

Two solutions are separated by a selectively permeable membrane. If solution A has a higher concentration of a nonpermeating solute than solution B, then __________.

Water will pass down its concentration gradient from solution B to A

A reduction in the number of glucose carrier proteins within the plasma membrane __________ the rate of glucose diffusion.

decreases

At this point, the addition of more solute _____ increase the amount of solute being transported.

does not

During osmosis, water will move _____ its own concentration gradient until equilibrium has been reached.

down

A red blood cell is placed in a hypotonic solution. This means that the concentration of solutes in the solution is _____ the concentration of solutes in the intracellular fluid and the cell will _____.

lower than; swell

Enzymes from the _____ degrade and digest the bacterium.

lysosome

A wondering _____ encounters a bacterium.

macrophage

Simple diffusion is defined as the movement of __________.

molecules from areas of higher concentration to areas of lower concentration

Primary and secondary active transport proteins differ in that primary active transport proteins __________.

move both molecules against their gradients, while secondary active transport proteins couple the movement of an ion down its gradient with the movement of another molecule against its gradient

At some point, all carriers are _____ and solute cannot be moved any faster.

occupied

Certain white blood cells engulf microorganisms and bring them in to digest them. This process is best described as _____

phagocytosis

Phagocyosis and pinocytosis differ in that __________.

phagocytosis allows for the transport of larger particles than pinocytosis

Lysosomes fuse with the phagosome to form a _____

phagolysosome

When completely surrounded, the bacterium is brought inside the cell membrane and forms a _____.

phagosome

Which molecule will require cellular energy to cross the plasma membrane? glycerol molecule non-polar molecule carbon dioxide oxygen polar molecule

polar molecule

Extending outwards from the macrophage, _____ are formed to encircle the bacterium.

pseudopods

The most specific type of endocytosis is __________.

receptor-mediated endocytosis

Osmosis is the net flow of water from one side of a _____ permeable membrane to the other.

selectively

Small lipid-soluble molecules slip directly through the phospholipid bilayer by the process of

simple diffusion

The sodium-potassium pump functions to pump ___________.

sodium ions out of the cell and potassium ions into the cell

Facilitated diffusion is used to transport ___________.

sugars and amino acids

Sodium and glucose are transported together from the intestinal lumen into an intestinal cell. The carrier protein is a(n) __________ and the process is called __________.

symport; cotransport

The _____ now moves back to the cell membrane which it fuses once again.

vesicle

Changes in the membrane potential trigger the opening or closing of __________.

voltage-gated channels

The normal movement of water across this membrane is from high to low _____ concentration.

water

Osmosis is best defined as the movement of __________.

water molecules across a membrane from an area of high-water concentration an area of lower concentration