Question 1

Biological membranes are one dimensional fluids.
__________________

Accepted Answer

two

Question 2

Which of the following statements about the sodium-potassium pump is true?

Accepted Answer

The sodium-potassium pump actively transports 3 sodium ions out of the cell and 2 potassium ions into the cell, maintaining the electrochemical gradient.

Question 3

In cells that are constantly involved in secretion, an equivalent amount of membrane must be returned to the interior of the cell for each vesicle that fuses with the plasma membrane; if this does not occur, then what would happen?

Accepted Answer

If the membrane is not returned to the interior of the cell, the cell surface will keep expanding due to the continuous addition of vesicle membranes to the plasma membrane.

Question 4

A human white blood cell engulfs a bacterial cell by:

Accepted Answer

Phagocytosis is the process by which a cell engulfs large particles or cells, such as bacteria, by surrounding them with its membrane, forming a vesicle. This is how white blood cells ingest bacterial cells.

Question 5

Figure 5-2
Use the figure to answer the corresponding question(s). 
-Select the receptor mediated endocytosis events that are in the correct (before, after) order:

Accepted Answer

Ligand binding to receptors and the formation of a coated vesicle by endocytosis is the initial step in receptor-mediated endocytosis.

Question 6

Plasmodesmata of plant cells are functionally equivalent to __________ of animal cells.

Accepted Answer

Plasmodesmata in plant cells and gap junctions in animal cells both serve as channels that allow for communication and transport of materials between adjacent cells.

Question 7

Compare and contrast simple diffusion, osmosis, and facilitated diffusion.

Accepted Answer

The answer of Compare and contrast simple diffusion, osmosis, and...

Question 8

One difference between tight junctions and dermatomes is that tight junctions:

Accepted Answer

Tight junctions are regions where the plasma membranes of two neighboring cells are in actual contact, forming a barrier to prevent the passage of materials between the cells.

Question 9

Compare and contrast the structure and functions of three of the following four intercellular junctions: desmosomes, gap junctions, tight junctions, and plasmodesmata.

Accepted Answer

The answer of Compare and contrast the structure and functions...

Question 10

Which of the following describes how facilitated diffusion is powered?

Accepted Answer

Energy is required to do the work of establishing and maintaining a concentration gradient.

Question 11

Figure 5-2
Use the figure to answer the corresponding question(s). 
-The process illustrated in Figure 5-2 would most likely be used to transport:

Accepted Answer

The answer of Figure 5-2
Use the figure to answer the...

Question 12

Pinocytosis:

Accepted Answer

Pinocytosis is a form of endocytosis where the cell ingests extracellular fluid and its dissolved solutes by the inward pinching of the plasma membrane, and it is nonspecific.

Question 13

A person has a genetic disease that prevents the phospholipids in the plasma membrane of the white blood cells from freely fusing with the other membranes within the cell.How would this disease affect phagocytosis?

Accepted Answer

The disease would prevent the phagocytic vacuole from fusing with the lysosome, which is necessary for the digestion of engulfed particles during phagocytosis.

Question 14

A bacterium containing sodium ions at a concentration of 0.1 mM lives in a pond that contains sodium ions at 0.005 mM.Evidently, sodium ions are entering the cell by:

Accepted Answer

The sodium ions are moving against their concentration gradient (from lower concentration in the pond to higher concentration inside the bacterium), which requires energy, indicating active transport.

Question 15

Using correct terminology, describe what would happen to a red blood cell placed in a solution of 0.5% sodium chloride.

Accepted Answer

The answer of Using correct terminology, describe what would happen...

Question 16

Receptor-mediated endocytosis:

Accepted Answer

Receptor-mediated endocytosis is an active process that involves the selective uptake of specific molecules by binding to receptors on the cell surface, leading to their enclosure in membranous vesicles for internalization.

Question 17

Figure 5-2
Use the figure to answer the corresponding question(s). 
-The process illustrated in Figure 5-2 is called:

Accepted Answer

The answer of Figure 5-2
Use the figure to answer the...

Question 18

In the mechanism of action of a proton pump, the role of ATP is to:

Accepted Answer

ATP provides the energy needed for the proton pump to actively transport protons (H+) from the inside of the cell to the outside, against their concentration gradient.

Question 19

In the cotransport of glucose and sodium ions:

Accepted Answer

In cotransport, sodium ions move down their concentration gradient, which provides the energy to transport glucose against its concentration gradient.

Question 20

The structures in this figure:

Accepted Answer

The answer of The structures in this figure: 
...

Quiz 5: Biological Membranes

Biological membranes are one dimensional fluids. __________________