intro to enzymes & cell metabolism miller levine 2.4 2010

intro to enzymes & cell metabolism miller levine 2.4 2010

Multiple Choice

True or False. Organisms must obey the law of conservation of energy and matter as they complete metabolism.

• true

• false

Multiple Choice

Every time an organism converts energy from one form to another--like when moving or carrying out an energy absorbing chemical reaction or breaking ATP to use its energy--cells give off and lose some energy as:

• ADP

• light

• heat

• sound

Multiple Choice

A warm blooded organism's stable body body heat and body temperature is due to:

• friction of proteins moving as they work

• loss of energy as heat during every energy conversion

• both are true

• neither is true

Multiple Choice

When attach to the phosphate group broken off of ATP, a cell's proteins

• change size

• are destroyed or turned "off"

• change shape & are usually "turned on"

Multiple Choice

During the light dependent reactions of photosynthesis and during the electron transport chain phase of aerobic cellular respiration, the spinning of enzyme ATP sythase provides _ energy that is converted to both heat and _ energy as it catalyzes the reaction ADP + Pi -->ATP.

• chemical potential, heat

• kinetic, chemical potential

• heat, light

Multiple Choice

After ATP is broken to ATP, a _ is usually attached to protein, changing its shape in a way that provides it with energy and allows it to do its type of cell work.

• photon

• mitochondrian

• ribosome

• phosphate group

Multiple Choice

A chemical reaction that is considered cell work because energy must be absorbed to store in new chemical bonds as smaller molecules are assembed into larger ones is_

• anabolic

• exothermic

• catabolic

• impossible

Multiple Choice

The hydrolysis of ATP-->ADP + Pi + energy is

• catabolic

• energy absorbing

• endothermic

• anabolic

Multiple Choice

The energy diagram below describes a chemical reaction that was

• energy releasing

• exothermic

• catabolic

• endothermic

Multiple Choice

What kind of reaction usually causes the environment to get warmer because heat is released. In a cell, some of the energy could be stored as ATP instead of being released as heat.

• endothermic

• exothermic

• metabolic

• anabolic

Multiple Choice

In the whoosh bottle demo, the activation energy of the chemical reaction was

• the heat that made the bottle warm

• the fire leaping in and out of the bottle

• the oxygen in the air

• the fire on the match or lighter

• the alcohol in the bottle

Multiple Choice

The chemical reaction used in the whoosh bottle demo, combustion of alcohols in oxygen, was

• endotermic

• exothermic

• endergonic

• energy absorbin

Multiple Choice

Which ethanol bottle took the longest for its reaction to be completed because its rate of reaction (speed) was lowest?

• the one with the highest concentration --95%--alcohol

• the one with the medium concentration --82%--alcohol

• the one with the ;lowest concentration --70%--alcohol

Multiple Choice

What of the 3 lines shows the condition having the highest rate (speed)?

• bottom

• middle

• top

Multiple Choice

What's so special for organisms about the ATP cycle and the process of cell respiration?

• It allows some of food molecule energy to be stored as chemical energy that can later be used for cell work

• It alllows all of food molecule energy to be immediately released as heat

Multiple Choice

true or false? Only endothermic, energy absorbing, anabolic chemical reactions require activation energy to be absorbed from the environment.

• true

• False

Multiple Choice

The source of activation energy is

• ATP hydrolysis

• glucose

• heat in the environment

Multiple Choice

Why is it important that organisms remain very near their normal body temperatures?

• to avoid denaturation of their proteins

• to avoid having too many chemical reactions activated

Multiple Choice

What happens to a protein that has been denatured?

• its shape is abnormal

• It can't work correctly anymore

• it may have been exposed to an extreme temperature, salt concentration, pH, or motion.

• all of the above

Multiple Choice

The role of an enzyme in a cell is to

• speed up a particular chemical reaction

• lower the activation energy of a particular chemical reaction

• act as a catalyst

• lower the temperature at which a particular reaction can be activated

• all of the above

Multiple Choice

Which of these two reactions was catalyzed by an enzuyme? (on the right side graph)?

• the one with a solid line

• the one with dashed line

Multiple Choice

the part of an enzme protein which must have exactly the same shape as the reactant and that squeezes up on it to lower activation energy is called the

• regulatory site

• active site

• peptide bond