Checkpoint Answers

1
Chapter 4

• Checkpoint Answers

2
Checkpoint 1

•  In the reaction (H2O CO2 ? H2CO3), increasing
  the concentration of H2O would
•  A. decrease the concentration of
  H2CO3.B. increase the concentration of
  H2CO3.C. increase the concentration of
  CO2.D. have no effect on either CO2 or H2CO3
  concentrations.

3
Checkpoint 2

• 1. Energy transformations result in a(n)
  ______________ in entropy. 
  A. increase B. decrease C. no change
• 2. Oxidizing agents accept electrons from
  molecules undergoing reduction. (T)
• 3.  A reducing agent donates electrons to a
  molecule. (T)
• 4.  Exergonic reactions proceed with the release
  of energy. (T)
• 5.  A molecule that gains a hydrogen is also
  oxidized. (F)
• 6.  Chemically reduced FAD has __________ extra
  hydrogen atom(s) bound to it.  A. one
  B. two C. three D. no
• 7.  Oxidized nicotinamide adenine dinucleotide
  (NAD) has ______________ two hydrogens. 
  A. lost B. gained C. shared

4
Chapter 5

• Checkpoint Answers

5
Checkpoint 1

• 1. ______________ is the opposite of
  glycogenesis. A. GlycolysisB. GlyconeogenesisC
  . GlycogenolysisD. Gluconeogenesis
• 2. Glucose formed from amino acids comes from the
  process of glycogenolysis.  (F)
• 3. The Cori cycle involves formation of glucose
  made by gluconeogenesis in the liver from lactic
  acid produced by fermentation in skeletal
  muscles. (T)

6
Checkpoint 2

• 1. In glycolysis, glucose is converted to
  glycogen.  (F)
• 2. Glycolysis converts glucose into two
  ______________ molecules. A. glycogen
  B. lactic acid C. acetyl CoA D. pyruvic
  acid
• 3. Acetyl CoA and NAD are the end-products of the
  Krebs Cycle.  (F)
• 4. Each turn of the Krebs cycle produces A. 2
  FADH2, 1 ATP, and 3 NADH. B. 1 FADH2, 1
  ATP, and 3 NADH.C. 3 FADH2, 2 ATP, and 1 NADH.
  D. 1 FADH2, 3 ATP, and 2 NADH
• 5. The actual yield of ATP from 1 glucose
  is A. 18-20 ATP. B. 36-38 ATP.C. 30-32
  ATP. D. 26-28 ATP.

7
Checkpoint 3

• 1. Which of the following can undergo metabolic
  conversion to acetyl CoA and enter the Krebs
  cycle? A. glucose B. fatty
  acidsC. protein D. All of these
  choices are correct.
• 2. The majority of energy within the body is
  stored as triglycerides. (T)
• 3. Acetyl CoA A. can enter the Krebs
  cycle.B. can reversibly form ketone
  bodies.C. can directly form pyruvic
  acid.D. Both can enter the Krebs cycle and can
  reversibly form ketone bodies.
• 4. How many amino acids are essential for an
  adult? A. eight B. nine C. ten
  D. twelve

8
Chapter 6

• Checkpoint Answers

9
Checkpoint 1

• 1. The majority of water within the body is found
  in the A. intracellular compartment. B. extrace
  llular compartment.C. blood plasma. D. intersti
  tial fluid.
• 2. The extracellular matrix is made up of
  collagen, elastin, and a gel-like ground
  substance. (T)
• 3. Active transport does not require the
  expenditure of energy.  (F)
• 4. Proteins that extend from the cytoskeleton
  within the cell, through the plasma membrane, and
  into the extracellular matrix are A. lysosomal
  proteins. B. metallo proteins.C. receptor
  proteins. D. integrin proteins.

10
Checkpoint 2

• 1. Passive transport of water is known
  as A. filtration. B. osmosis.C. facilitated
  diffusion. D. a water pump.
• 2. Dialysis uses the process of A. facilitated
  diffusion. B. primary active transport.C. simpl
  e diffusion. D. secondary active transport.
• 3. The rate of diffusion increases as the
  concentration gradient increases. (T)
• 4. What type of intravenous fluid would be given
  to reduce edema? A. hypertonic
  B. isotonic C. hypotonic
• 5. Explain the difference between osmolarity and
  osmolality. (read full explanation in your
  testbook)

11
Checkpoint 3

• 1. Protein carrier mediated transport of
  molecules display A. specificity. B. competitio
  n.C. saturation. D. All of these choices are
  correct.
• 2. Glucose can enter into the cell by facilitated
  diffusion or countertransport.  (F fasc. diff or
  cotransport)
• 3. Active transport carriers are also
  called A. vesicles. B. channels.C. pumps. D
  . receptors.
• 4. What type of functional complex will prohibit
  paracellular transport? A. tight
  junctions B. adherens junctionsC. desmosomes D.
   gap junctions
• 5. Movement of large molecules into a cell is
  called A. endocytosis. B. exocytosis.C. bulk
  transport. D. Both A and C are correct.

12
Checkpoint 4

• 1. The charge difference across a membrane
  produces the membrane potential.  (T)
• 2. The resting membrane potential is closest to
  the equilibrium potential for A. sodium
  ions. B. chloride ions.C. calcium
  ions. D. potassium ions.
• 3. Hyperkalemia would ____________ the resting
  membrane potential of the cell. A. increase
  B. decrease C. have no effect on
• 4. A change in the concentration of any ion
  inside or outside the cell will change the
  resting potential. (T)

13
Checkpoint 5

• 1. Which of the following is NOT a general
  category of cell signaling molecules? A. endocrin
  e signaling B. enzymatic signalingC. paracrine
  signaling D. synaptic signaling
• 2. Which of the following is NOT true of cyclic
  AMP? A. It is found on the outside of a plasma
  membrane.B. It is a second messenger for polar
  regulatory molecules.C. It is made from
  ATP.D. It activates enzymes inside a cell to
  produce the desired effect.
• 3. Where is the receptor for a nonpolar,
  lipid-soluble regulatory molecule? A. embedded
  in the outer surface of the plasma
  membraneB. embedded in the inner surface of the
  plasma membraneC. in the cytoplasm or nucleus
  of the cellD. All of the choices are correct.