SMARTBOOK- Transport Across Membranes

The sodium-potassium pump uses energy in the form of ______ to move ions against their concentration gradients.

ATP

The sodium-potassium pump moving Na+ out of the cell and K+ into the cell against their concentration gradients is an example of ______.

Active transport

What type of movement across membranes is shown in the picture and requires a transport protein and ATP?

Active transport

The solute molecules in this illustration of simple diffusion are moving ______ a concentration gradient to disburse throughout the cup.

Down

What process is occurring in the picture, reading from panel 1 at the top to panel 3 at the bottom?

Exocytosis

Membrane proteins called aquaporins allow ______ of water across membranes, as the movement of water solely by osmosis can be slow.

Facilitated diffusion

Select all of the substances that can pass freely through the membrane by simple diffusion.

Lipids Small nonpolar molecules Oxygen Carbon dioxide

In diffusion, a chemical concentration gradient dissipates, and thus diffusion represents the ______ of potential energy and does not require energy input.

Loss

The image shows the diffusion of water across a selectively permeable membrane, which is called ______.

Osmosis

Select all of the following that are true about the sodium-potassium pump.

Requires ATP, moves sodium out of the cell up its concentration gradient, moves potassium into the cell up it's concentration gradient

Match the methods of membrane transport with the correct descriptions.

Simple Diffusion- Movement of solutes from high to low concentration without a transport protein. Facilitated Diffusion- Movement of solutes from high to low concentration with a transport protein. Osmosis- Movement of water from areas of high water concentration (low solute concentration) to areas of low water concentration (high clout concentration). Active Transport- Movement of solutes from low to high concentration with a transport protein.

What happens during receptor-mediated endocytosis?

a cell brings substances that bind to membrane receptors

A substance is moved from an area where its concentration is low to an area where its concentration is high with the expenditure of energy in

active transport

What type of membrane transport requires energy (ATP) and transport proteins?

active transport

The sodium-potassium pump requires energy because both sodium and potassium ions move ______ their concentration gradients.

against

If a solute is more concentrated in one location than another, it forms

concentration gradient

After a concentration gradient disappears, molecules

continue to move randomly back and forth

The spontaneous movement of a substance from an area where it is more concentrated to an area where it is less concentrated is called ______.

diffusion

In a process called ______, a cell engulfs material and brings it into the cell in a vesicle pinched off the cell membrane.

endocytosis

What process is shown in the picture, reading it from the top panel to the bottom panel?

endocytosis

Pinocytosis is a type of __________.

endocytosis used by cells to engulf fluids and dissolved substances

A concentration gradient will dissipate unless ______ is expended to maintain a higher concentration in one area compared to the other.

energy

In passive transport, no _________ is spent to pass a substance across a membrane.

energy

At equilibrium, molecules continue to move back and forth between areas of solution at ______ rates, creating ______ concentrations throughout a solution.

equal, equal

In a membrane transport process called ______, a cell transports large molecules to the cell membrane in vesicles and releases them to the outside of the cell.

exocytosis

Membrane proteins assist ions and polar molecules across membranes down their concentration gradient in

facilitated diffusion

What type of membrane transport is shown in the picture and requires a carrier molecule, but not ATP?

facilitated diffusion

A concentration ______ occurs when there are unequal amounts of a solute in neighboring regions.

gradient

Hydrogen ions moving through a membrane protein release energy that is used to synthesize ATP. In this example of the potential energy in a concentration gradient, hydrogen ions are moving from a ____ concentration to a ____ concentration via facilitated diffusion.

high to low

A substance moving from an area where its concentration is ______ to an area where its concentration is ______ is moving down its concentration gradient.

higher, lower

If a solution has a higher solute concentration than a cell, then the solution is ______ compared to the cell.

hypertonic

If more water is exiting a human red blood cell than entering it, then the cell is in a(n) ______ solution.

hypertonic

If a solution has a higher solute concentration than a cell, then the solution is ______ compared to the cell.

hypotonic

If a solution has a lower solute concentration than the interior of a cell, then the solution is ______ compared to the cell interior.

hypotonic

If more water is entering a human red blood cell than exiting it, then the cell is surrounded by a(n) ______ solution.

hypotonic

In an isotonic solution, the solute concentration

is equal between two neighboring areas

If an equal amount of water enters and exits a human red blood cell, then the cell's interior is ______ to the cell's exterior.

isotonic

The concentrations of solutes between the interior and the exterior of a cell or organelle may be chemically different because the ______ is selectively permeable

membrane

The diffusion of water across a membrane down its own concentration gradient and toward the region with a higher solute concentration is called

osmosis

What is the process whereby an ion, an atom, or a molecule crosses a membrane without using energy?

passive transport

In diffusion, a substance moves by ______.

passive transport to a region where the substance is less concentrated

In what process does a cell capture large particles in vesicles and bring them into the cell?

phagocytosis

________ is a type of endocytosis used by cells to engulf bulk matter, including debris and other cells.

phagocytosis

During what process does a cell engulf small amounts of fluids or dissolved substances using vesicles and bring the substances into the cell?

pinocytosis

A concentration gradient is a form of ______ energy because energy that can be used to drive molecular motion is stored in the gradient.

potential

Simple diffusion does not require energy because it is a result of ______ molecular motion.

random

In a process called ______, molecules to be brought into the cell first bind to receptor proteins on the cell's surface, and then a vesicle forms and brings the molecules into the cell.

receptor-mediated endocytosis

Membranes of organelles and cells only allow specific ions, atoms, and molecules to pass because membranes are

selectively permeable

Substances such as lipids and small nonpolar molecules move freely through the cell membrane without the need for transport proteins in a process called

simple diffusion

The movement of substances down their concentration gradient without the use of transport proteins is called ______.

simple diffusion

What type of membrane transport is shown in the picture and lacks a carrier molecule?

simple diffusion

______ pressure is the force of water against a plant cell wall and helps maintain the shape of plant cells.

turgor

Plant cells are hypertonic compared to the surrounding soil. This helps to promote water movement into the cell, which generates

turgor pressure