biology chapter 5

which of these is hydrophobic like the interior of the plasma membrane?

Lipid soluble molecule

Which part of the ATP molecule breaks free of the rest when an ATP molecule is used for energy?

Part D

Substrates bind to an enzyme's ________ site.

active

the movement of atoms, ions, or molecules from a region of higher concentration to regions of lower concentration is called _____.

diffusion

the diffusion of water across a selectively permeable membrane is called _____.

osmosis

Oxygen crosses a plasma membrane by

passive transport

The process of a white blood cell engulfing a bacterium is

phagocytosis

Most enzymes are

proteins

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

proteins

Enzymes work by _____.

reducing activation energy

What name is given to the reactants in an enzymatically catalyzed reaction?

substrate

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

exergonic; endergonic

mechanisms such as ______________, enable precise control over a cell's ______________- all of its chemical reactions

feedback inhibition; metabolism

What type of reaction breaks the bonds that join the phosphate groups in an ATP molecule?

hydrolysis

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

hypertonic

a plant cell placed in a(n) _____ solution will lose water and plasmolyze.

hypertonic

an animal cell placed in a(n) _______ solution will gain water, swell, and possibly burst

hypotonic

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

When placed in a hypotonic environment, where the solute concentration is below that of the cell, a houseplant will _____.

remain standing upright

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

Structure A in the figure is a(n) _____.

transport protein

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

transport proteins; down

The transfer of a phosphate group to a molecule or compound is called

phosphorylation

there are three main types of cellular work: chemical, transport, and movement. most of this work is powered by the transfer of a phosphate group from one molecule to another in a process known as _____.

phosphorylation

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

Cell A

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.

A child is brought to the hospital with a fever of 107°F. doctors immediately order an ice bath to lower the child's temperature. which of the following statements offers the most logical explanation for this action.

elevated body temperature may denature enzymes. this would interfere with the cells abilities to catalyze various reactions

What is the correct label for "A"?

energy of activation

A specific ______ speeds up each of a cell's chemical reactions.

enzyme

through energy coupling, cells use _________, or energy releasing, reactions to drive _________, or energy requiring, reactions. the molecule ________is the energy shuttle between these two types of reactions.

exergonic; endergonic; ATP

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 ideal osmotic environment for a plant cell is a(n) ___ environment.

hypotonic

in the lab you use a special balloon that is permeable to water but not sucrose to make an artificial cell. The balloon is filled with a solution of 20% sucrose and 80% water and is immersed in a beaker containing a solution of 40% sucrose and 60% water. the solution in the ballon is ______ relative to the solution in the beaker.

hypotonic

An enzyme

is an organic catalyst

As a result of its involvement in a reaction, an enzyme _____.

is unchanged

A plant cell surrounded by a(n) ___ solution will be flaccid (limp).

isotonic

the ideal osmotic environment for an animal cell is a(n) ______ environment

isotonic

Anything that prevents ATP formation will most likely

result in cell death

plasma membranes are selectively permeable. this means that

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

which of the following is an accurate comparison of active transport and facilitated diffusion

Active transport moves solutes against their concentration gradient; facilitated diffusion moves substances down their concentration gradient.

cellular respiration is an example of ________.

an exergonic process

cells store energy that they use for work in the ________.

arrangement of atoms within molecules

Light is _____ energy, which is converted into _____ energy by plants.

kinetic ... chemical