BIO 1693 MIDTERM 2 EXAM
QUESTIONS AND ANSWERS. VERIFIED
2025/2026.
What are the 3 monosaccharides absorbed by the digestive system? - ANS glucose, fructose,
and galactose (but they all get converted to glucose for ATP prodcution)
What are the two fates of glucose once absorbed? - ANS glucose is either oxidized by the
cells to create ATP or stored in the body
How can glucose be stored in the body? - ANS 1. Glucose can be stored by the liver and
skeletal muscle cells as glycogen (glycogenesis).
2. If the glycogen stores are full glucose can be converted to triglycerides by the liver cells to be
stored in adipose tissue.
3. Some cells can use glucose to create amino acids.
How does glucose enter the cell? - ANS facilitated diffusion, sped up by insulin
List the four sets of reactions in glucose metabolism - ANS 1. glycolysis
2. formation of acetyl coenzyme A
3. Krebs cycle
4. electron transport chain
Describe glycolysis - ANS -The first stage of cellular respiration which occurs in the cytosol.
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, -the 6-carbon glucose molecule is split into two 3-carbon pyruvic acid molecules
-hydrogen is added to coenzyme NAD to create NADH+H^+
for every two pyruvic acid molecules two ATPs are produced. This reaction does not require
oxygen.
Describe the formation of acetyl coenzyme A - ANS The formation of acetyl coenzyme A
prepares pyruvic acid for the entrance into the Krebs Cycle.
-Pyruvic acid is split into 2-carbon fragment by the removal of CO2.
-NAD is converted to NADH+H
-the remaining atoms called an acetyl group are combined with coenzyme A to create acetyl
coenzyme A
this all occurs in a mitochondrion
Describe the Krebs Cycle - ANS A series of reactions that transfers hydrogen atoms to the
coenzymes NAD and FAD
-NADH+H and FADH2 are created
-For every 2 acetyl coenzyme A that enters the Krebs cycle, 2 ATP are produced
-most of the energy is stored in NADH+H and FADH2 and in order for it to be freed up their
hydrogen electrons must pass through the electron transport chain
Describe the electron transport chain - ANS During glycolysis, the formation of acetyl
coenzyme A and the krebs cycle hydrogen many hydrogen atoms were formed.
-The hydrogen atoms get split into hydrogen ions and electrons
-the hydrogen ions create a gradient in which the electrons travel down with oxygen being the
final electron acceptor
-during this process ATP and water are produced
How much ATP does one glucose molecule produce in total? - ANS 30 or 32
Define glycogenesis - ANS The synthesis of glycogen from glucose to be stored in liver and
skeletal muscle cells. stimulated by insulin
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
QUESTIONS AND ANSWERS. VERIFIED
2025/2026.
What are the 3 monosaccharides absorbed by the digestive system? - ANS glucose, fructose,
and galactose (but they all get converted to glucose for ATP prodcution)
What are the two fates of glucose once absorbed? - ANS glucose is either oxidized by the
cells to create ATP or stored in the body
How can glucose be stored in the body? - ANS 1. Glucose can be stored by the liver and
skeletal muscle cells as glycogen (glycogenesis).
2. If the glycogen stores are full glucose can be converted to triglycerides by the liver cells to be
stored in adipose tissue.
3. Some cells can use glucose to create amino acids.
How does glucose enter the cell? - ANS facilitated diffusion, sped up by insulin
List the four sets of reactions in glucose metabolism - ANS 1. glycolysis
2. formation of acetyl coenzyme A
3. Krebs cycle
4. electron transport chain
Describe glycolysis - ANS -The first stage of cellular respiration which occurs in the cytosol.
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, -the 6-carbon glucose molecule is split into two 3-carbon pyruvic acid molecules
-hydrogen is added to coenzyme NAD to create NADH+H^+
for every two pyruvic acid molecules two ATPs are produced. This reaction does not require
oxygen.
Describe the formation of acetyl coenzyme A - ANS The formation of acetyl coenzyme A
prepares pyruvic acid for the entrance into the Krebs Cycle.
-Pyruvic acid is split into 2-carbon fragment by the removal of CO2.
-NAD is converted to NADH+H
-the remaining atoms called an acetyl group are combined with coenzyme A to create acetyl
coenzyme A
this all occurs in a mitochondrion
Describe the Krebs Cycle - ANS A series of reactions that transfers hydrogen atoms to the
coenzymes NAD and FAD
-NADH+H and FADH2 are created
-For every 2 acetyl coenzyme A that enters the Krebs cycle, 2 ATP are produced
-most of the energy is stored in NADH+H and FADH2 and in order for it to be freed up their
hydrogen electrons must pass through the electron transport chain
Describe the electron transport chain - ANS During glycolysis, the formation of acetyl
coenzyme A and the krebs cycle hydrogen many hydrogen atoms were formed.
-The hydrogen atoms get split into hydrogen ions and electrons
-the hydrogen ions create a gradient in which the electrons travel down with oxygen being the
final electron acceptor
-during this process ATP and water are produced
How much ATP does one glucose molecule produce in total? - ANS 30 or 32
Define glycogenesis - ANS The synthesis of glycogen from glucose to be stored in liver and
skeletal muscle cells. stimulated by insulin
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
