bio: ch. 5

Molecules that come from the food we eat provide energy for the work that goes on inside our cells. This energy, stored inside our food, is a form of ____

potential energy called chemical energy.

Diffusion _____.

proceeds until a dynamic equilibrium is reached

Most enzymes are ____.

proteins

Which environments would be best for the functioning of plant and animal cells?

A hypotonic environment for plant cells and an isotonic environment for animal cells.

In cells, what is usually the immediate source of energy for an endorgonic reaction?

ATP

What compound directly provides energy for cellular work?

ATP

In your body, what process converts the chemical energy found in glucose into the chemical energy found in ATP?

cellular respiration

The plasma membrane forms a pocket that pinches inward, forming a vesicle that contains material from outside the cell. This describes the process of

endocytosis.

A person eats one hard-boiled egg and digests the egg fully. During cellular respiration most of the Calories in the egg turn into _____

heat

Which of these are by-products of cellular respiration?

heat and water

In cellular respiration, most energy is released and transferred to ATP when ______.

high-energy electrons "fall" to lower energy levels.

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

hydrolysis

An object at rest has no _____ energy, but it may have _____ energy resulting from its location or structure.

kinetic; potential.

The sum total of all the chemical reactions that occur in organisms is called ______.

metabolism

In active transport,

molecules move across the plasma membrane against their concentration gradient

Humans convert approximately ______ of the energy stored in food to useful work.

34%

The region of an enzyme to which a substrate binds is called the ______ site.

active

Which statement about an enzyme is TRUE?

An enzyme's function depends on its three-dimensional shape.

How are combustion and cellular respiration different?

Cellular respiration breaks down sugar, and combustion breaks down octane.

Which statement about enzymes is TRUE?

Enzymes catalyze specific reations

What is the function of ATP?

It provides energy for cellular work.

Which of these is exhibiting kinetic energy?

a space station orbiting Earth

Which process could result in the net movement of a substance into a cell, if the substance is more concentrated than the cell in the surroundings?

active transport

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

active transport.

In a hypotonic solution, a plant cell will _____.

become turgid

Active transport _____.

can involve the transport of ions.

The principle that energy cannot be created or destroyed is known as _____.

conservation of energy.

Enzymes increase the rate of a reaction by

decreasing activation energy

The reaction ADP + P = ATP is a ______ reaction.

endergonic

"Conservation of energy" refers to the fact that _____.

energy cannot be created or destroyed but converted from one form to another

Which of the following is a measure of randomness in a system?

entropy

What molecules are scientists currently trying to use to generate power for nanotechnology devices, such as microscopic robots?

enzymes

A _____ reaction occurs spontaneously.

exergonic

The energy for an endergonic reaction comes from a _____ reaction.

exergonic

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

exhibit a net movement to the side with lower water concentration

When a person cries, tears are exported from cells. Which category of transport most precisely matches this process?

exocytosis

Cells with a higher concentration of ions than the surrounding medium tend to _____.

expand

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

facilitated diffusion

Substances that plug up an enzyme's active site are enzyme ______.

inhibators.

Endocytosis move materials _____ a cell via _____.

into ..... membranous vesicles

An enzyme _____.

is an organic catalyst

A cell that neither gains nor loses a net amount of water at equilibrium when it is immersed in a solution is ____.

isotonic to its environment.

What is the fate of the phosphate group that is removed when ATP is converted to ADP?

it is acquired by a reactant in an endergonic reaction

What biological process did scientists use as inspiration for engineering enzymes to remove molecular tags from red blood cells?

natural selection

Which of the following is highest in chemical energy?

one molecule of glucose

What name is given to the process by which water crosses a selectively permeable membrane?

osmosis

Diffusion is an example of ______.

passive transport

Facilitated diffusion is a type of _____.

passive transport

A white blood cell engulfing a bacterium is an example of ______.

phagocytosis

ATP energizes other molecules in cells by transferring a _____ to those molecules.

phosphate group

Which of these molecules spontaneously form membranes when mixed in water and most likely were one of the first organic compounds formed on Earth?

phospholipids

Chemical energy is a form of _____ energy.

potential

Osmosis can be defined as _____.

the diffusion of water across a selectively permeable membrane

Enzymes work by _____.

reducing activation energy

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

relative inelasticity and strength of the plant cell wall

Anything that prevents ATP formation will most likely

result in cell death

An enzyme's function is most dependent on its _____.

shape

Kinetic energy is energy in motion. Potential energy is _____ energy.

stored

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

substrate

Energy can be defined as _____.

the capacity to cause change.

What is energy coupling?

the use of energy released from an exergonic reaction to drive an endergonic reaction

Water crosses the plasma membrane

through facilitated diffusion or diffusion.

Energy is conserved. This means that in any system,

total energy input equals total energy output.

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

transport proteins; down