Chapter 5 (exam 2)

Question 1

Fluid Mosaic Model

Answer 1

Currently accepted model of cell membrane structure, which envisions the membrane as a mosaic of protein molecules drifting laterally in a fluid bilayer of phospholipids.

Question 2

Amphipathic

Answer 2

Having both a hydrophobic and hydrophillic region

Question 3

Glycoproteins

Answer 3

proteins with one or more covalently attached carbohydrates

Question 4

Glycolipids

Answer 4

A lipid with one or more covalently attached carbohydrates

Question 5

Selective Permeability

Answer 5

A property of biological membranes that allows them to regulate the passage of substances across them.

Question 6

Transport Proteins

Answer 6

A transmembrane protein that helps a certain substance or class of closely related substances to cross the membrane

Question 7

concentration gradient

Answer 7

A region along which the density of a chemical substance increases or decreases.

Question 8

osmosis

Answer 8

The diffusion of free water molecules across a selectively permeable membrane

Question 9

hypertonic

Answer 9

A solution that when surrounding a cell, will cause the cell to lose water

Question 10

hypotonic

Answer 10

A solution that when surrounding the cell, will cause the cell to take up water

Question 11

isotonic

Answer 11

Referring to a solution that, when surrounding a cell, causes no net movement of water into or out of the cell.

Question 12

facilitated diffusion

Answer 12

The passage of molecules or ions down their electrochemical gradient across a biological membrane with the assistance of specific transmembrane transport proteins, requiring no energy expenditure.