5.1 - 5.11 Mastering Review

Which of the following processes can move a solute against its concentration gradient?

active transport

Aquaporins

allow water to cross the plasma membrane via facilitated diffusion.

Membrane phospholipids

are able to drift about in the plasma membrane.

A plant cell in a hypotonic solutio

becomes turgid because of an inflow of water.

The fluid mosaic model describes the plasma membrane as consisting of

diverse proteins embedded in a phospholipid bilayer.

Phagocytosis is to eating as pinocytosis is to

drinking.

Small, nonpolar, hydrophobic molecules such as fatty acids

easily pass through a membrane's lipid bilayer.

When a cell uses chemical energy to perform work, it uses the energy released from a(n) ________ reaction to drive a(n) _____

exergonic; endergonic

When two aqueous solutions that differ in solute concentration are placed on either side of a semipermeable membrane and osmosis is allowed to take place, the water will

exhibit a net movement to the side with lower free water concentration.

Certain cells that line the stomach synthesize a digestive enzyme and secrete it into the stomach. This enzyme is a protein. Which of the following processes could be responsible for its secretion?

exocytosis

The cholesterol associated with animal cell membranes

helps to keep phospholipids from being too close to one another.

Some protozoans have special organelles called contractile vacuoles that continually eliminate excess water from the cell. The presence of these organelles tells you that the environment

is hypotonic to the protozoan.

A cell that has neither a net gain of water nor net loss of water when it is immersed in a solution must be

isotonic to its environment.

In a hypotonic solution, an animal cell will

lyse.

Diffusion does not require the cell to expend ATP. Therefore, diffusion is considered a type of

passive transport.

Oxygen crosses a plasma membrane by

passive transport.

The process of a white blood cell engulfing a bacterium is

phagocytosis.

Most of the functions of a cell membrane, including transport and enzymatic function, are performed by

proteins.

The molecules responsible for membrane transport are

proteins.

Cells acquire low-density lipoproteins (LDLs) by

receptor-mediated endocytosis.

All cells are enclosed by a plasma membrane that is similar in ________ and ________.

structure; function

Osmosis can be defined as

the diffusion of water.

Plasma membranes are selectively permeable. This means that

the plasma membrane allows some substances to enter or leave a cell more easily than others.

If placed in tap water, an animal cell will undergo lysis, whereas a plant cell will not. What accounts for this difference?

the relative inelasticity and strength of the plant cell wall

Which of the following processes is endergonic?

the synthesis of glucose from carbon dioxide and water

Which figure depicts an animal cell placed in a solution hypotonic to the cell?

top left/ figure A

Facilitated diffusion across a biological membrane requires ________ and moves a substance ________ its concentration gradient

transport proteins; down

What is the basic difference between exergonic and endergonic reactions?

Exergonic reactions release energy; endergonic reactions absorb it.

Which of the following statements is true for all types of passive transport?

The concentration gradient is the driving force.

Which of the following is a typical feature of an ATP-driven active transport mechanism?

The solute moves against the concentration gradient.