BIO TEST QUESTIONS UNIT 5B

After a dye diffuses uniformly throughout a glass of water, the dye molecules are no longer moving. True or False?

False

Osmosis is the diffusion of water molecules across selectively water-permeable membranes. True or False?

True

Imagine an artificial cell made with a selectively permeable membrane that allows water to pass through but does not allow sugar to pass. If you fill this cell with a 1% sugar solution and then you place the cell in a 2% sugar solution, what happens?

Water leaves the cell.

Two aqueous solutions are separated by a selectively permeable membrane that allows water to pass through but does not allow starch to pass through. Solution A is 10% starch and solution B is 5% starch. What will occur?

Water will diffuse from solution B to solution A.

For diffusion to occur, there must be:

a gradient.

Many metabolic poisons work by inhibiting ATP production. Which type of transport would be most affected?

active transport

Diffusion is the movement of molecules from __________.

an area of higher concentration of that type of molecule to an area of lower concentration

Active transport requires all of the following EXCEPT

aquaporins

Which of the following processes does a cell use to take up molecules against their concentration gradient?

both active transport and endocytosis

Which of the following associations is not correct?

desmosomes-allow inflexible attachments among cells

A freshwater protozoan, such as Paramecium, tends to ________ because it lives in a ________ environment.

gain water; hypotonic

Solutions that cause water to enter cells by osmosis are called:

hypotonic.

To say that a cell is "selectively permeable" means:

only certain molecules can pass through.

Choose the substance that will diffuse most rapidly across the plasma membrane.

oxygen

Two types of connections between cells, called "gap junctions" and "plasmodesmata," are specialized to __________.

permit the passage of substances (e.g., ions) between cells through small passageways that directly link the cytoplasm of one cell to the cytoplasm of another cell

The process in which white blood cells engulf bacteria is termed:

phagocytosis.

You observe a cell under a microscope and you can clearly see a cell wall, a vacuole, and cytoplasmic connections. These cytoplasmic connections must be:

plasmodesmata.

Cell membranes do all of the following EXCEPT:

provide shape and structure to a cell.

Each substance needs a different type of transport to get into a cell. Pick the answer choices that accurately match the type of transport needed to convey each of the following substances into a cell.oxygen, water, sodium ions, potassium ions, bacteria (Note that sodium ions are more concentrated outside cells than inside; potassium ions are more concentrated inside cells than outside.)

simple diffusion, osmosis, facilitated diffusion, active transport, endocytosis

If a frog egg cell is placed into a hypotonic solution, it will:

swell via osmosis.

The fluid mosaic model describes membranes as fluid because __________.

the phospholipids and proteins move from place to place within the bilayer

The cells of the intestinal epithelium (lining) are joined to one another by ________ that prevent substances from passing between the cells of this tissue.

tight junctions

Facilitated diffusion and active transport both require ________ for the movement of molecules across the membrane.

transport proteins

Which of the following groups includes carrier and channel proteins?

transport proteins

Which of the following types of membrane proteins are responsible for facilitated diffusion?

transport proteins