Deck 1: Cellular Biology

Question 1

A eukaryotic cell is undergoing DNA replication. In which region of the cell would most of the genetic information be contained?

A) Mitochondria
B) Ribosome
C) Nucleolus
D) Nucleus

Answer 1

Nucleolus

Question 2

An athlete runs a marathon, after which his muscles feel fatigued and unable to contract. A deficiency in which of the following would cause impaired muscle contraction?

A) GTP
B) AMP
C) ATP
D) GMP

Answer 2

ATP

Question 3

Pancreatic beta cells secrete insulin, which inhibits secretion of glucagons from neighboring alpha cells. This action is an example of which of the following signaling types?

A) Paracrine
B) Autocrine
C) Neurohormonal
D) Hormonal

Answer 3

Paracrine

Question 4

The fluid mosaic model for biologic membranes describes membrane behavior. According to this model, which of the following float singly or as aggregates in the fluid lipid bilayer?

A) Peripheral membrane proteins
B) Integral membrane proteins
C) Glycoproteins
D) Cell adhesion molecules

Question 5

Electrolytes are:

A) small lipid-soluble molecules.
B) large protein molecules.
C) micronutrients used to produce ATP.
D) electrically charged molecules.

Question 6

The movement of small, electrically uncharged molecules through a semipermeable barrier is an example of:

A) osmosis.
B) diffusion.
C) hydrostatic pressure.
D) active transport.

Question 7

An isolated cell is observed to absorb oxygen and use it to transform nutrients to energy. Which of the following cellular functions is it displaying?

A) Metabolic absorption
B) Communication
C) Secretion
D) Respiration

Question 8

A tissue capillary bed has a hydrostatic pressure of 25 mm Hg and an oncotic pressure of 10 mm Hg. The filtration pressure is _____ mm Hg.

A) 5
B) 10
C) 15
D) 20

Question 9

Plasma membrane receptors are available to bind to:

A) oxygen.
B) ribosomes.
C) amphipathic lipids.
D) ligands.

Question 10

A cell is isolated for microscopy. It is observed to have supercoiled DNA with histones. Which of the following would also be observed?

A) Single circular chromosome
B) Nucleus
C) Freely floating nuclear material
D) No organelles

Question 11

A patient with metastatic cancer would be expected to have alterations in extracellular matrix that include:

A) decreased fibronectin.
B) increased collagen.
C) decreased elastin.
D) increased glycoproteins.

Question 12

In cirrhosis, how does cholesterol alter the fluidity of the plasma membrane of erythrocytes?

A) Cholesterol decreases the membrane fluidity of the erythrocyte, which reduces its ability to carry oxygen.
B) Cholesterol decreases the membrane fluidity of erythrocytes, which reduces its ability to carry hemoglobin.
C) Cholesterol increases the membrane fluidity of erythrocytes, which allows binding of excess glucose.
D) Cholesterol increases the membrane fluidity of erythrocytes, which prolongs its life span beyond 120 days.

Question 13

The three phases of cellular catabolism are:

A) digestion, glycolysis and oxidation, and the citric acid cycle.
B) diffusion, osmosis, and mediated transport.
C) S phase, G phase, and M phase.
D) metabolic absorption, respiration, and excretion.

Question 14

The phase of catabolism during which ATP production is highest is:

A) digestion.
B) glycolysis.
C) oxidation.
D) citric acid cycle.

Question 15

A patient has a body fluid of 300 mOsm/kg. This measure is termed:

A) osmolality.
B) osmolarity.
C) osmotic pressure.
D) effective osmolality.

Question 16

Which form of cell communication is used to communicate with other cells in direct physical contact?

A) Cell junction
B) Gap junction
C) Desmosomes
D) Tight junctions

Question 17

Oncotic pressure (colloid osmotic pressure) is determined by:

A) concentration of sodium.
B) plasma proteins.
C) hydrostatic pressure.
D) availability of membrane transporter proteins.

Question 18

Which of the following is true regarding the predominant extracellular cation?

A) Has a positive charge
B) Migrates toward the positive pole
C) Is sodium
D) Is potassium

Question 19

In cellular metabolism, each enzyme has a high affinity for a:

A) solute.
B) substrate.
C) receptor.
D) ribosome.

Question 20

A runner has depleted all the oxygen available for muscle energy. Which of the following will facilitate his continued muscle performance?

A) Electron-transport chain
B) Aerobic glycolysis
C) Anaerobic glycolysis
D) Oxidative phosphorylation

Question 21

At rest, the membrane potential is nearly the equilibrium potential for potassium. Why is potassium able to diffuse easily in and out of cells?

A) Because potassium has a greater concentration in the intracellular fluid (ICF)
B) Because sodium has a greater concentration in the extracellular fluid (ECF)
C) Because the resting plasma membrane is more permeable to potassium
D) Because there is an excess of anions inside the cell

Question 22

The ion transporter that moves Na⁺ and Ca²⁺ simultaneously in the same direction is an example of which of the following types of transport?

A) Active mediated transport
B) Uniport
C) Antiport
D) Symport

Question 23

A patient who has diarrhea receives a hypertonic saline solution intravenously to replace the sodium and chloride lost in the stool. What effect will this fluid replacement have on cells?

A) Cells will become hydrated.
B) Cells will swell or burst.
C) Cells will shrink.
D) Cells will divide.

Question 24

The phase of the cell cycle during which the centromeres split and the sister chromatids are pulled apart is referred to as:

A) anaphase.
B) telophase.
C) prophase.
D) metaphase.

Question 25

A cell is isolated and electrophysiology studies reveal that the resting membrane potential is -70 millivolts. The predominant intracellular ion is Na⁺ and the predominant extracellular ion is K⁺. With voltage change, which of the following would result in an action potential?

A) K⁺ rushing into the cell
B) Na⁺ rushing into the cell
C) Na⁺ rushing out of the cell
D) K⁺ rushing out of the cell

Question 26

Platelet-derived growth factor stimulates the production of:

A) platelets.
B) epidermal cells.
C) connective tissue cells.
D) fibroblast cells.

Question 27

What causes the rapid change in the resting membrane potential that initiates an action potential?

A) Potassium gates open, and potassium rushes into the cell changing the membrane potential from negative to positive.
B) Sodium gates open, and sodium rushes into the cell changing the membrane potential from negative to positive.
C) Sodium gates close, allowing potassium into the cell to change the membrane potential from positive to negative.
D) Potassium gates close, allowing sodium into the cell to change the membrane potential from positive to negative.

Question 28

The process during which lysosomal enzymes can be released to degrade engulfed particles is referred to as:

A) endocytosis.
B) pinocytosis.
C) phagocytosis.
D) exocytosis.

Question 29

A biopsy of the lung bronchi revealed ciliated epithelial cells that are capable of secretion and absorption. These cells are called:

A) simple columnar epithelium.
B) ciliated simple columnar epithelium.
C) stratified columnar epithelium.
D) pseudostratified ciliated columnar epithelium.

Question 30

The cellular uptake of cholesterol depends on:

A) active mediated transport.
B) the antiport system.
C) receptor-mediated endocytosis.
D) passive transport.

Question 31

How are potassium and sodium transported across plasma membranes?

A) By passive electrolyte channels
B) By coupled channels
C) By adenosine triphosphate enzyme (ATPase)
D) By diffusion

Question 32

How is the transport of glucose from the blood to the cell accomplished?

A) By active-mediated transport (active transport)
B) By active diffusion
C) By passive osmosis
D) By passive-mediated transport (facilitated diffusion)

Question 33

The movement of fluid across the arterial end of capillary membranes into the interstitial fluid surrounding the capillary is an example of which process of fluid movement?

A) Hydrostatic pressure
B) Osmosis
C) Diffusion
D) Active transport

Question 34

What is the role of cytokines in cell reproduction?

A) Provide growth factor for tissue growth and development
B) Block progress of cell reproduction through the cell cycle
C) Restrain cell growth and development
D) Provide nutrients for cell growth and development

Question 35

The phase during the cell cycle where nuclear and cytoplasmic division occurs is called:

A) G₁.
B) S.
C) M.
D) G₂.