Chapter 25 Quiz (100%)

Identify the molecule labeled "7."

hydrogen atoms citric acid *4 carbon molecule NADH FADH2

Identify the molecule labeled "1."

hydrogen atoms citric acid *pyruvic acid NADH FADH2

Identify the molecule labeled "2."

hydrogen atoms citric acid 4 carbon molecule *carbon dioxide FADH2

Identify the molecule labeled "6."

hydrogen atoms citric acid 4 carbon molecule NADH *FADH2

A(n) ________ acts as an intermediary that accepts electrons from one molecule and transfers them to another molecule.

hydrogen ion *coenzyme acetyl group cytochrome electron

During glycolysis

*a molecule of glucose is converted into two molecules of pyruvic acid. 6 molecules of ATP are produced. carbon dioxide is produced. NADH2 molecules attach to the cytochromes. more energy is used than is released.

The TCA cycle

*begins with the formation of a molecule of citric acid. directly produces most of the ATP from the catabolism of glucose. does not form any carbon dioxide. contains enzymes called cytochromes. forms acetyl-CoA from glucose-6-phosphate.

Identify the molecule labeled "4."

*hydrogen atoms citric acid 4 carbon molecule NADH FADH2

Urea is formed in the

*liver. stomach. kidneys. small intestine. large intestine.

The function of the citric acid cycle is to

*remove hydrogen atoms from organic molecules and transfer them to coenzymes. transfer the acetyl group. perform a hydrolysis reaction with surrounding cells. produce ATP and ADP. fight the mitochondria.

The major cation in extracellular fluid that is essential for normal membrane function is

*sodium. potassium. calcium. magnesium. iron.

The process of deamination produces

keto acids. urea. *ammonia. acetyl-CoA. B vitamins.

In order for glycolysis to occur, ________ must be present

glucose molecules appropriate cytoplasmic enzymes ATP and ADP NAD *all of these

The sum of all of the biochemical processes going on within the human body at any given time is called

glycolysis. oxidative phosphorylation. catabolism. anabolism. *metabolism.

The carbon dioxide of respiration is formed during

glycolysis. the TCA cycle. electron transport. the transition step *both answers 2 and

All of the following are true of beta-oxidation, except that

it occurs in the mitochondria. it is the process that breaks down fatty acids into two-carbon fragments that can be metabolized by the TCA cycle. *excess lipids are converted into glycogen molecules. it requires coenzyme A, NAD, and FAD. it yields large amounts of ATP.

The major steps in oxidative phosphorylation include all of the following, except

removal of hydrogen atoms from a substrate molecule by coenzymes. ionization of hydrogen atoms. increasing the energy level of electrons passing through the electron transport chain. *the rupture of carbon-carbon double bonds. the loss of electrons by oxygen atoms.

The major cation in cytoplasm that is essential for membrane function is

sodium. *potassium. calcium. magnesium. iron

A cation that is essential for muscle contraction, nerve function, and blood clotting is

sodium. potassium. *calcium. magnesium. selenium.

In oxidative phosphorylation, energy for the synthesis of ATP is provided by

the splitting of oxygen molecules. the breaking of the covalent bonds in glucose. *the movement of hydrogen ions through channels in the respiratory enzymes. the combination of two atoms of hydrogen and one atom of oxygen to form water. the oxidation of acetyl-CoA.