EXAM 3

A calorie is a commonly used unit of chemical energy. It is also the unit of

• heat

• sound

• light

• radioactivity

The energy used by humans ultimately originates from what source?

• animals

• water

• sun

• air

If the AG of a reaction was -31.45 kJoules, you would know that

• the reaction requires an energy input of 31.45 kloules to proceed

• the products have more free energy than the reactants

• the reaction is spontaneous

• the reaction most likely leads to development of a more ordered system

Energy is defined as

• change

• movement

• the capacity to do work

• heat

The chemistry of living systems representing all chemical reactions is called

• enzymology

• thermodynamics

• metabolism

• anabolism

When the substrate is bound to the enzyme, the shape of the enzyme may change slightly, leading to

• a great range of possible catalytic activities

• an induced fit

• more permanent binding through intimate total contact

• more possible products of the reaction

Many metabolic pathways involve ATP; either generating ATP, or requiring ATP. Why is ATP so important to metabolism?

• Hydrolysis of the bond between adenine and ribose in ATP is commonly used to release energy that can be used to drive other cellular reactions.

• Hydrolysis of ATP is used to drive exergonic reactions.

• The phosphate groups of ATP are held together by unstable bonds that can be broken to release energy.

• ATP is a protein that serves as the energy currency of cells.

In animals that take in oxygen from their environment, glucose is broken down into carbon dioxide and water in a process called

• organic compound respiration

• glucose respiration

• anaerobic respiration

• aerobic respiration

What are the products of one turn of the citric acid cycle?

• 4 C02, 6 NADH, 2 FADH2. 2 ATP

• 4 CO2. 12 NADH, 4 FADH,. 4 ATP

• 2 C02, 3 NADH, 1 FADH2, 1 ATP

• 2 CO2, 6 NADH, 2 FADH2, 2ATP

In the reaction catalyzed by aconitase, the conversion of citrate to isocitrate can be inhibited by fluoroacetate. Fluoroacetate is used as a pesticide. Why is this an effective pesticide?

• It inhibits ATP synthase.

• It inhibits the electron transport chain.

• it inhibits pyruvate oxidation.

• It inhibits the citric acid cycle.