Mastering A&P Ch.25

What needs to be present for glycolysis to proceed

NAD, ATP, glucose, ADP

All the available nutrient molecules distributed in the blood form a

Nutrient pool

How food fuels cellular respiration

a. Eating food provides fuel and building blocks for your body b. After food is broken down in the digestive system, it is transported to cells via the circulatory system c. Fuel molecules are broken down further in glycolysis and the citric acid cycle d. ATP is produced with the help of the electron transport chain

Lipogenesis generally begins with

acetyl-CoA

Lipogenesis is common for organic molecules because the intermediate ________ is formed in most nutrient metabolic processes.

acetyl-CoA

Synthesis of fatty acids starts with __________.

acetyl-CoA

Growth and repair involve primarily what type of reactions?

anabolic

The complete catabolism of fatty acids is through the process called

beta-oxidation

Heat loss to the cooler air that moves across the surface of your body is called

convection

The trace element needed as a cofactor for hemoglobin synthesis is

copper

Carbon and oxygen atoms are removed as carbon dioxide in a process called

decarboxylation

Which of the following occurs when water is released (lost) during a reaction?

dehydration synthesis

The loss of heat energy by vaporizing water is called

evaporation

True of beta-oxidation

fatty acids break down into two-carbon fragments. it occurs in the mitochondria. it yields large amounts of ATP. it requires coenzyme A, NAD, and FAD.

Steps in glycolysis

1. As soon as the glucose molecule enters the cytosol, a phosphate group is attached to the molecule 2. A second phosphate group is attached. Together' steps 1 and 2 cost the cell 2 ATP 3. The six carbon chain is split into two three-carbon molecules, each of which then follows the rest of this pathway. 4. As another phosphate group is attached to each molecule, and NADH is generated from NAD. 5. One ATP molecule is formed for each molecule processed 6. The atoms in each molecule are rearranged, releasing a molecule of water. 7. A second ATP molecule is formed for each molecule processed. Step 7 produces 2 ATP molecules

Glycolysis produces how many pyruvate molecules and how many ATP molecules? (Figure 25-2)

2 pyruvate molecules with a net gain of 2 ATP molecules

Following a meal, the absorptive state lasts approximately

4 hours

The vitamin that plays a role in maintaining epithelia and is required for the synthesis of visual pigments is vitamin

A

Taking excess vitamins can be dangerous. It is possible to overdose on vitamin

A - fat soluble

Which of the following statements about ADH (antidiuretic hormone) is correct?

ADH is released by the posterior pituitary gland.

Which of the following statements about aldosterone is NOT correct?

Aldosterone increases sodium reabsorption by increasing the number of Na+-K+ ATPase pumps in the luminal membrane of the proximal tubule.

Fatty acids and many amino acids cannot be used for ________ because their catabolic pathways produce acetyl-CoA.

gluconeogenesis

The process of synthesizing glucose from noncarbohydrates is called

gluconeogenesis

Which of the following processes takes place in the cytosol of a eukaryotic cell?

glycolysis

Select the correct sequence of steps as energy is extracted from glucose during cellular respiration.

glycolysis → acetyl CoA → citric acid cycle → electron transport chain

An element that is a component of hemoglobin, myoglobin, and cytochromes is

iron

What is the osmolarity of the filtrate at the end of the proximal tubule?

isotonic - 300 mOsm

The vitamin that is essential for the production of several clotting factors is vitamin

k

The condition where the blood pH drops because of ketone bodies in the blood is called __________.

ketoacidosis

All of the following occur during the postabsorptive state

ketone bodies may be formed. fat mobilization occurs. glycogenolysis occurs in the liver. gluconeogenesis occurs in the liver.

The vitamin that prevents breakdown of vitamin A and fatty acids is vitamin

E

Fat-soluble vitamin overdoses primarily affect which organ?

liver

A cation that often acts as a cofactor for enzymes is

magnesium

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

metabolism

Where does beta-oxidation take place? (Figure 25-7)

mitochondria

The citric acid cycle occurs in the

mitochondrial matrix

In what organelle would you find acetyl CoA formation, the citric acid cycle, and the electron transport chain?

mitochondrion

In oxidative phosphorylation, energy for the synthesis of ATP is directly obtained from the

movement of hydrogen ions through channels in the inner mitochondrial membrane.

During starvation,

muscle proteins are used as an energy source.

The vitamin that is part of the coenzyme NAD is

niacin

An ion that is a necessary component of high-energy compounds and nucleic acids and a structural component of bone is the ________ ion.

phosphate

The major cation in cytoplasm is

potassium

A vitamin obtained that is a coenzyme in amino acid and lipid metabolism is

pyridoxine (B6)

What is the function of the urea cycle?

reduce the concentration of ammonia

The amino group that is removed from an amino acid during deamination is converted to the less toxic form of __________.

urea

A way to conserve or generate heat?

vasoconstriction in the skin shivering thermogenesis nonshivering thermogenesis release of thyroxine

The two most important coenzymes for glycolysis and the citric acid cycle are

NAD FAD

Reactions within ________ provide most of the energy needed by a typical cell.

Mitochondria

During amino acid catabolism, the enzyme that removes the amino group from amino acids requires a co-enzyme derived from vitamin __________.

B6

Oxygen is an important molecule in which of the following?

CAC and ETS

The carbon dioxide of respiration is formed during

Citric acid cycle

The vitamin that is required for proper bone growth and for calcium absorption and retention is vitamin

D

Most of the ATP from metabolism is produced in the

ETS

The smallest lipoproteins, called __________, transport cholesterol from peripheral tissues to the liver.

HDL

________ carry excess cholesterol from peripheral tissues to the liver.

HDLs

Glycolysis yields two molecules of pyruvate. Which of the following statements best describes what next happens to pyruvate?

In the presence of oxygen, pyruvate enters a mitochondrion.

What two types of lipoproteins are manufactured by the liver? (Figure 25-8)

LDL VLDL

Lipoproteins are water-soluble because of a superficial coating of

Phospholipids and proteins

Nitrogen Compounds

Purines and pyrimidines Amino Acids Porphyrins Creatine

When NAD+ is ________ it becomes NADH. When NADH is ________ it becomes NAD+.

Reduced; oxidized

Lipoproteins that are primarily sent to skeletal muscles and adipose tissues are called

VLDL

Which statement describes the citric acid cycle?

This process produces some ATP and carbon dioxide in the mitochondrion.

Which statement describes glycolysis?

This process splits glucose in half and produces 2 ATPs for each glucose.

Which statement describes the electron transport chain?

This process uses energy captured from electrons flowing to oxygen to produce most of the ATPs in cellular respiration.

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

calcium

The electron transport system doesn't produce ATP directly instead it uses the hydrogen ion gradient to drive

chemiosmosis

The major anion in body fluids is

chloride

In the citric acid cycle, a 2 carbon molecule and a 4 carbon molecule combine to produce

citric acid

In the ETS, ________ accepts electrons from one molecule and transfers them to another.

coenzyme

Intermediary molecules that accept electrons and transfer them to another molecule are called

coenzymes

The direct transfer of heat energy from one object to another through physical contact is called

conduction

The function of the citric acid cycle is to

remove hydrogen atoms from organic molecules and transfer them to coenzymes.

The vitamin that is part of the coenzyme FAD is

riboflavin

An important trace mineral that acts as an antioxidant is

selenium

The major cation in extracellular fluid is

sodium

In a warm environment, does more blood return to the trunk through deep or superficial veins? Why? (Figure 25-14)

superficial veins; allows heat to radiate

Catabolism of protein is not a practical source of quick energy because

the energy yield from protein is less than the yield from lipids. proteins are more difficult to break apart than lipids or carbohydrates. extensive catabolism of protein threatens homeostasis. one of the by-products of protein catabolism is ammonia.

During the absorptive state,

the liver forms glycogen

The term ________ refers to the homeostatic process that allows us to maintain a constant body temperature.

thermoregulation

The vitamin whose deficiency causes beriberi is

thiamine

In transamination, the amino group of an amino acid is

transferred to a keto acid

What is the role of NADH in metabolism?

transport hydrogen atoms to coenzymes

The element that is necessary for the proper function of the enzyme carbonic anhydrase is

zinc