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NU 545 UNIT 1 EXAM 2026 |100 QUESTIONS AND
CORRECT DETAILED ANSWERS | RATED A+ | NEW AND
REVISED
1. 1. What is metabolic absorption?: Metabolic absorption is the process by which cells take in nutrients, water,
ions, and other substances from their environment to fuel metabolism, produce energy, and maintain cellular structures.
This process is essential for sustaining cell function and responding to environmental changes.
2. 2. What uses oxygen to remove hydrogen atoms in an oxidative reaction?: - Peroxisomes use
oxygen to remove hydrogen atoms from specific substrates, generating hydrogen peroxide (H2O2) as a byproduct.
Enzymes like catalase then break down H2O2 to prevent damage.
Peroxisomes are crucial for detoxification, fatty acid metabolism, and nerve cell myelination.
3. 3. During cell injury, what is released that is capable of cellular autodiges- tion?:
Lysosomes release enzymes such as proteases, lipases, and nucleases during cell injury.
These enzymes digest cellular components, leading to autodigestion (autolysis) and contributing to cell death if the damage persists.
4. 4. Where is the genetic information contained in the cell?: Genetic information is stored in the
nucleus, which houses DNA and histones that regulate gene activity.
A small amount of DNA is also found in mitochondria, essential for mitochondrial function and energy production.
5. 5. Cell membranes contain which major chemical components? Cell mem- branes
consist of:: Phospholipids (forming a bilayer).
Proteins (receptors, transport channels, enzymes). Cholesterol
(stabilizing membrane fluidity).
Carbohydrates (glycolipids, glycoproteins) for signaling and protection.
6. 6. What allows potassium to diffuse in and out of cells?: Potassium channels in the cell membrane
allow potassium ions to move in and out of cells along their concentration gradient, maintaining resting membrane potential and
supporting cellular functions like nerve impulse transmission.
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7. 7. How is the cell protected from injury?: Cells are protected by: Plasma
membrane: Barrier against harmful substances.
Glycocalyx: Cushions and protects against damage.
Cytoskeleton: Maintains structure and absorbs mechanical stress. Antioxidants:
Neutralize free radicals.
Repair mechanisms: Fix DNA and maintain membrane integrity.
8. 8. In cirrhosis, what does cholesterol have to do with erythrocytes?: In cirrhosis, abnormal
cholesterol metabolism alters erythrocyte membranes, reducing their flexibility and increasing fragility.
This leads to hemolysis, target cell formation, and anemia.
9. 9. What is platelet-derived growth factor (PDGF )?: PDGF is a signaling protein that stimulates cell growth,
proliferation, and repair.
It plays a key role in wound healing, tissue regeneration, and angiogenesis (formation of new blood vessels).
10. 10. What is cell communication, and how does it occur?: Cell communication involves sending
and receiving signals to coordinate activities. It occurs through:
Chemical signaling: Hormones, neurotransmitters, cytokines. Direct
contact: Gap junctions, membrane-bound signals.
Autocrine, paracrine, and endocrine mechanisms.
11. 11. What is chemical signaling?: Chemical signaling involves the release of molecules (e.g., hor- mones,
cytokines, neurotransmitters) that bind to specific receptors on target cells, triggering a response.
It includes autocrine, paracrine, and endocrine signaling.
12. 12. How is glucose transported from the blood to the cell? Glucose enters cells via::
Facilitated dittusion: Through GLUT transporters, driven by a concentration gradient.
NU 545 UNIT 1 EXAM 2026 |100 QUESTIONS AND
CORRECT DETAILED ANSWERS | RATED A+ | NEW AND
REVISED
1. 1. What is metabolic absorption?: Metabolic absorption is the process by which cells take in nutrients, water,
ions, and other substances from their environment to fuel metabolism, produce energy, and maintain cellular structures.
This process is essential for sustaining cell function and responding to environmental changes.
2. 2. What uses oxygen to remove hydrogen atoms in an oxidative reaction?: - Peroxisomes use
oxygen to remove hydrogen atoms from specific substrates, generating hydrogen peroxide (H2O2) as a byproduct.
Enzymes like catalase then break down H2O2 to prevent damage.
Peroxisomes are crucial for detoxification, fatty acid metabolism, and nerve cell myelination.
3. 3. During cell injury, what is released that is capable of cellular autodiges- tion?:
Lysosomes release enzymes such as proteases, lipases, and nucleases during cell injury.
These enzymes digest cellular components, leading to autodigestion (autolysis) and contributing to cell death if the damage persists.
4. 4. Where is the genetic information contained in the cell?: Genetic information is stored in the
nucleus, which houses DNA and histones that regulate gene activity.
A small amount of DNA is also found in mitochondria, essential for mitochondrial function and energy production.
5. 5. Cell membranes contain which major chemical components? Cell mem- branes
consist of:: Phospholipids (forming a bilayer).
Proteins (receptors, transport channels, enzymes). Cholesterol
(stabilizing membrane fluidity).
Carbohydrates (glycolipids, glycoproteins) for signaling and protection.
6. 6. What allows potassium to diffuse in and out of cells?: Potassium channels in the cell membrane
allow potassium ions to move in and out of cells along their concentration gradient, maintaining resting membrane potential and
supporting cellular functions like nerve impulse transmission.
,2|Page
7. 7. How is the cell protected from injury?: Cells are protected by: Plasma
membrane: Barrier against harmful substances.
Glycocalyx: Cushions and protects against damage.
Cytoskeleton: Maintains structure and absorbs mechanical stress. Antioxidants:
Neutralize free radicals.
Repair mechanisms: Fix DNA and maintain membrane integrity.
8. 8. In cirrhosis, what does cholesterol have to do with erythrocytes?: In cirrhosis, abnormal
cholesterol metabolism alters erythrocyte membranes, reducing their flexibility and increasing fragility.
This leads to hemolysis, target cell formation, and anemia.
9. 9. What is platelet-derived growth factor (PDGF )?: PDGF is a signaling protein that stimulates cell growth,
proliferation, and repair.
It plays a key role in wound healing, tissue regeneration, and angiogenesis (formation of new blood vessels).
10. 10. What is cell communication, and how does it occur?: Cell communication involves sending
and receiving signals to coordinate activities. It occurs through:
Chemical signaling: Hormones, neurotransmitters, cytokines. Direct
contact: Gap junctions, membrane-bound signals.
Autocrine, paracrine, and endocrine mechanisms.
11. 11. What is chemical signaling?: Chemical signaling involves the release of molecules (e.g., hor- mones,
cytokines, neurotransmitters) that bind to specific receptors on target cells, triggering a response.
It includes autocrine, paracrine, and endocrine signaling.
12. 12. How is glucose transported from the blood to the cell? Glucose enters cells via::
Facilitated dittusion: Through GLUT transporters, driven by a concentration gradient.
