Chapter 01: Cellular Biology

MULTIPLE CHOICE

1. Which statement best describes the cellular function of metabolic absorption?

a. Cells can produce proteins.

b. Cells can secrete digestive enzymes.

c. Cells can take in and use nutrients.

d. Cells can synthesize fats.

ANS: C

In metabolic absorption, all cells take in and use nutrients and other substances from their 

surroundings. The remaining options are not inclusive in their descriptions of cellular metabolic 

absorption.

PTS: 1 DIF: Cognitive Level: Remembering

2. Where is most of a cell’s genetic information, including RNA and DNA, contained?

a. Mitochondria

b. Ribosome

c. Nucleolus

d. Lysosome

ANS: C

The nucleus contains the nucleolus, a small dense structure composed largely of RNA, most of 

the cellular DNA, and the DNA-binding proteins, such as the histones, which regulate its 

activity. The mitochondria are responsible for cellular respiration and energy production. 

Ribosomes’ chief function is to provide sites for cellular protein synthesis. Lysosomes function 

as the intracellular digestive system.

PTS: 1 DIF: Cognitive Level: Remembering

3. Which component of the cell produces hydrogen peroxide (H2O2) by using oxygen to remove 

hydrogen atoms from specific substrates in an oxidative reaction?

a. Lysosomes

b. Peroxisomes

c. Ribosomes

d. Endosome

ANS: B

Test Bank - Pathophysiology: The Biologic Basis for Disease in Adults and Children (8th) 5

Peroxisomes are so named because they usually contain enzymes that use oxygen to remove 

hydrogen atoms from specific substrates in an oxidative reaction that produces H2O2, which is a 

powerful oxidant and potentially destructive if it accumulates or escapes from peroxisomes. 

Ribosomes are RNA-protein complexes (nucleoproteins) that are synthesized in the nucleolus 

and secreted into the cytoplasm through pores in the nuclear envelope called nuclear pore 

complexes. Lysosomes are saclike structures that originate from the Golgi complex and contain 

more than 40 digestive enzymes called hydrolases, which catalyze bonds in proteins, lipids, 

nucleic acids, and carbohydrates. An endosome is a vesical that has been pinched off from the 

cellular membrane.

PTS: 1 DIF: Cognitive Level: Remembering

4. Which cell component is capable of cellular autodigestion when it is released during cell injury?

a. Ribosome

b. Golgi complex

c. Smooth endoplasmic reticulum

d. Lysosomes

ANS: D

The lysosomal membrane acts as a protective shield between the powerful digestive enzymes 

within the lysosome and the cytoplasm, preventing their leakage into the cytoplasmic matrix. 

Disruption of the membrane by various treatments or cellular injury leads to a release of the 

lysosomal enzymes, which can then react with their specific substrates, causing cellular selfdigestion. The chief function of a ribosome is to provide sites for cellular protein synthesis. The 

Golgi complex is a network of flattened, smooth vesicles and membranes often located near the 

cell nucleus. The smooth endoplasmic reticulum is involved in steroid hormone production and 

removing toxic substances from the cell.

PTS: 1 DIF: Cognitive Level: Remembering

5. Which cAMP-mediated response is related to antidiuretic hormone?

a. Increased heart rate and force of contraction

b. Secretion of cortisol

c. Increased retention of water

d. Breakdown of fat

ANS: C

Antidiuretic hormone leads to increased retention of water in the body. Epinephrine causes 

increases in heart rate and force of contraction. Increased cortisol secretion is due to ACTH. 

Breakdown of fat is due to glucagon.

PTS: 1 DIF: Cognitive Level: Remembering

6. During which phase of the cell cycle is DNA synthesized?

a. G1

b. S

c. G2

d. M

Test Bank - Pathophysiology: The Biologic Basis for Disease in Adults and Children (8th) 6

ANS: B

The four designated phases of the cell cycle are: (1) the G1 phase (G = gap), which is the period 

between the M phase (M = mitosis) and the start of DNA synthesis; (2) the S phase (S = 

synthesis), during which DNA is synthesized in the cell nucleus; (3) the G2 phase, during which 

RNA and protein synthesis occurs, the period between the completion of DNA synthesis and the 

next phase (M); and (4) the M phase, which includes nuclear and cytoplasmic division.

PTS: 1 DIF: Cognitive Level: Remembering

7. What organic compound facilitates transportation across cell membranes by acting as receptors, 

transport channels for electrolytes, and enzymes to drive active pumps?

a. Lipids

b. Proteases

c. Proteins

d. Carbohydrates

ANS: C

Proteins have several functions, including acting as receptors, transport channels for electrolytes, 

and enzymes to drive active pumps Lipids help act as the “glue” holding cell membranes 

together. Proteases cause the breakdown of protein. Carbohydrates are involved in cellular 

protection and lubrication and help produce energy via oxidative phosphorylation.

PTS: 1 DIF: Cognitive Level: Remembering

8. Understanding the various steps of proteolytic cascades may be useful in designing drug therapy 

for which human diseases?

a. Cardiac and vascular disorders

b. Autoimmune and malignant disorders

c. Gastrointestinal and renal disorders

d. Endocrine and gastrointestinal disorders

ANS: B

Understanding the various steps involved in this process is crucial for designing drug 

interventions. Dysregulation of proteases features prominently in many human diseases, 

including cancer, autoimmunity, and neurodegenerative disorders. Cardiac, vascular, 

gastrointestinal, renal, and endocrine disorders do not involve this process.

PTS: 1 DIF: Cognitive Level: Remembering

9. Which structure prevents water-soluble molecules from entering cells across the plasma 

membrane?

a. Carbohydrate chains

b. Glycoprotein channels

c. Membrane channel proteins

d. Lipid bilayer

ANS: D

Test Bank - Pathophysiology: The Biologic Basis for Disease in Adults and Children (8th) 7

The bilayer’s structure accounts for one of the essential functions of the plasma membrane. It is 

impermeable to most water-soluble molecules (molecules that dissolve in water) because the 

water-soluble molecules are insoluble in the oily core region. The bilayer serves as a barrier to 

the diffusion of water and hydrophilic substances while allowing lipid-soluble molecules, such as 

oxygen (O2) and carbon dioxide (CO2), to diffuse through it readily. Carbohydrate chains, 

glycoprotein channels, and membrane channel proteins do not prevent water-soluble molecules 

from entering cells across the cell membrane.

PTS: 1 DIF: Cognitive Level: Remembering

10. A student asks for an explanation of the absolute refractory period of the action potential. What 

response by the professor is best?

a. A stronger than normal impulse will evoke another response.

b. No stimulus is able to evoke another response at this time.

c. Multiple stimuli can produce more rapid action potentials.

d. The hyperpolarized state means a weaker stimulus produces a response.

ANS: B

During the absolute refractory state of the action potential, no stimulus is able to evoke another 

response from the cell. A stronger than normal impulse may generate a response in the relative 

refractory period. This period of time is not related to the number of stimuli. A hyperpolarized 

state means a stronger than normal stimulus would be needed to generate a response.

PTS: 1 DIF: Cognitive Level: Remembering

11. Which form of cell communication is used to communicate within the cell itself and with other 

cells in direct physical contact?

a. Protein channel (gap junction)

b. Plasma membrane-bound signaling molecules

c. Hormone secretion such as neurotransmitters

d. Extracellular chemical messengers such as ligands

ANS: B

Cells communicate in three main ways; they display plasma membrane-bound signaling 

molecules that affect the cell itself and other cells in direct physical contact with it, they affect 

receptor proteins inside the target cell, and they form protein channels (gap junctions) that 

directly coordinate the activities of adjacent cells. Neurotransmitters are released by neurons and 

cross the synaptic cleft to communicate with the cells they innervate. Ligands are involved in 

binding processes.

PTS: 1 DIF: Cognitive Level: Remembering

12. Which mode of chemical signaling uses blood to transport communication to cells some distance 

away?

a. Paracrine

b. Autocrine

c. Neurotransmitter

d. Hormonal

Test Bank - Pathophysiology: The Biologic Basis for Disease in Adults and Children (8th) 8

ANS: D

Chemical signaling can be classified into three categories: (1) local-chemical mediator, (2) 

hormone, and (3) neurotransmitter. Hormones are released by one set of cells and travel through 

tissues or the bloodstream to another set of cells where they produce a response by those cells. In 

paracrine signaling, cells secrete local chemical mediators that are quickly absorbed, destroyed, 

or immobilized. Paracrine signaling requires close membrane-to-membrane contact. Paracrine 

signaling usually involves different cell types; however, cells also may produce signals that they, 

themselves, respond to, which is called autocrine signaling. Neurotransmitters are released by 

neurons and cross the synaptic cleft to communicate with the cells they innervate.

PTS: 1 DIF: Cognitive Level: Remembering

13. Which mode of chemical signaling uses local chemical mediators that are quickly taken up, 

destroyed, or immobilized?

a. Paracrine

b. Autocrine

c. Neurotransmitter

d. Hormone

ANS: A

In paracrine signaling, cells secrete local chemical mediators that are quickly taken up, 

destroyed, or immobilized. Autocrine signaling occurs when the target cells produce signals that 

they themselves respond to. Neurotransmitters are released by neurons and cross the synaptic 

cleft to communicate with the cells they innervate. Hormones are released by one set of cells and 

travel through tissues or the bloodstream to another set of cells where they produce a response by 

those cells.

PTS: 1 DIF: Cognitive Level: Remembering

14. Neurotransmitters affect the postsynaptic membrane by binding to which structure?

a. Lipids

b. Ribosomes

c. Amphipathic lipids

d. Receptors

ANS: D

In each type of chemical signaling, the target cell receives the signal by first attaching to its 

receptors. The other options do not correctly describe this process.

PTS: 1 DIF: Cognitive Level: Remembering

15. How do cells receive communication from the extracellular fluid surrounding them?

a. Protein channel (gap junction)

b. Plasma membrane-bound signaling molecules (involving receptors)

c. Hormone secretion such as neurotransmitters

d. Chemical messengers such as ligands

ANS: D

Test Bank - Pathophysiology: The Biologic Basis for Disease in Adults and Children (8th) 9

Signal transduction involves incoming signals or instructions from extracellular chemical 

messengers (ligands) that are conveyed to the cell’s interior for execution. The other options do 

not correctly describe how cells receive communication from the surrounding extracellular fluid.

PTS: 1 DIF: Cognitive Level: Remembering

16. Which molecule provides the second messenger necessary for extracellular communication to be 

activated?

a. Guanosine triphosphate (GTP)

b. Adenosine monophosphate (AMP)

c. Adenosine triphosphate (ATP)

d. Guanosine diphosphate (GDP)

ANS: B

The two major second-messenger pathways are cyclic AMP (cAMP) and calcium (Ca++). GTP, 

ATP, and GDP are not major second-messenger pathways. GTP and GDP are “middlemen” or 

intermediaries. Nutrients are transformed into energy in the form of ATP.

PTS: 1 DIF: Cognitive Level: Remembering

17. Under anaerobic conditions, what process provides energy for the cell?

a. Oxidative phosphorylation

b. Glycolysis

c. Lactolysis

d. Passive transport

ANS: B

Glycolysis provides energy to the cells when oxygen delivery is insufficient or delayed. 

Oxidative phosphorylation is the process by which energy produced from nutrients is transferred 

to ATP. Lactolysis is the breakdown of lactose. Passive transport is the movement of water and 

small, nonelectrically charge molecules across plasma membranes.

PTS: 1 DIF: Cognitive Level: Remembering

18. What is the mechanism by which the energy produced from carbohydrates, proteins, and lipids is 

transferred to adenosine triphosphate (ATP)?

a. Anaerobic glycolysis

b. Oxidative cellular metabolism

c. Oxidative phosphorylation

d. Tricarboxylic acid phosphorylation

ANS: C

Oxidative phosphorylation occurs in the mitochondria and is the mechanism by which the energy 

produced from carbohydrates, fats, and proteins is transferred to ATP. Glycolysis provides 

energy to the cells when oxygen delivery is insufficient or delayed. Oxidative cellular 

metabolism and tricarboxylic acid phosphorylation are not involved in transferring energy to 

ATP.

PTS: 1 DIF: Cognitive Level: Remembering

Test Bank - Pathophysiology: The Biologic Basis for Disease in Adults and Children (8th) 10

19. Passive transport is best described with which statement?

a. Being driven by osmosis, hydrostatic pressure, and diffusion

b. Involving receptors that can bind with substances being transported

c. Being capable of transporting macromolecules

d. Requiring energy generated by the cell

ANS: A

Water and small electrically uncharged molecules move easily through pores in the plasma 

membrane’s lipid bilayer. This process, called passive transport, naturally occurs through any 

semipermeable barrier. It is driven by osmosis, hydrostatic pressure, and diffusion, all of which 

depend on the laws of physics and do not require life. The other options do not correctly describe 

passive transport.

PTS: 1 DIF: Cognitive Level: Remembering

20. Which is the best example of active transport?

a. Movement across a membrane due to differences in solute concentration

b. Movement requiring the expenditure of metabolic energy

c. Movement of two molecules simultaneously in one direction

d. Movement of two molecules simultaneously in opposite directions

ANS: B

Active transport requires a life, biologic activity, and the expenditure of metabolic energy. 

Movement due simply to differences in concentration gradients is called passive transport. 

Movement of two molecules in the same direction is called symport, while moving two 

molecules in opposite directions is called antiport.

PTS: 1 DIF: Cognitive Level: Remembering

21. Which method of transport uses transmembrane proteins with receptors with a high degree of 

specificity for the substance being transported?

a. Active

b. Mediated

c. Transmembranous

d. Passive

ANS: B

Mediated transport (passive and active) involves integral or transmembrane proteins with 

receptors having a high degree of specificity for the substance being transported. Active and 

passive transport are opposites with active transport requiring the use of energy and passive 

transport relying on osmosis, hydrostatic pressure, and diffusion and not energy. 

Transmembranous means “across membranes.”

PTS: 1 DIF: Cognitive Level: Remembering

22. The movement of fluid across the arterial end of capillary membranes into the interstitial fluid 

surrounding the capillary is an example of which fluid movement process?

a. Hydrostatic pressure

Test Bank - Pathophysiology: The Biologic Basis for Disease in Adults and Children (8th) 11

b. Osmosis

c. Diffusion

d. Active transport

ANS: A

Hydrostatic pressure is the mechanical force of water pushing against cellular membranes. 

Osmosis is the movement of water “down” a concentration gradient, that is, across a 

semipermeable membrane from a region of higher water concentration to a region of lower water 

concentration. Diffusion is the movement of a solute molecule from an area of greater solute 

concentration to an area of lesser solute concentration. Active transport requires a life, biologic 

activity, and the expenditure of metabolic energy.