5 Vocabulary

Question 1

Active Transport

Answer 1

The movement of a substance across a biological membrane against its concentration gradient, aided by specific transport proteins and requiring an input of energy (often as ATP)

Question 2

Adenosine Triphosphate (ATP)

Answer 2

Adenosine triphosphate, the main energy source for cells. ATP releases energy when its phosphate bonds are hydrolyzed

Question 3

Concentration Gradient

Answer 3

A region along which the density of a chemical substance increases or decreases.Cells often maintain concentration gradients of ions across their membranes. When a concentration gradient exists, substances tend to move from where they are more concentrated to where they are less concentrated

Question 4

Diffusion

Answer 4

The random movement of particles that results in the net movement of a substance down its concentration gradient from a region where it is more concentrated to a region where it is less concentrated

Question 5

Endocytosis

Answer 5

Cellular uptake of molecules or particles via formation of new vesicles from the plasma membrane

Question 6

Exocytosis

Answer 6

The movement of materials out of a cell by the fusion of vesicles with the plasma membrane

Question 7

Facilitated Diffusion

Answer 7

The passage of a substance through a specific transport protein across a biological membrane across its concentration gradient

Question 8

Fluid Mosaic

Answer 8

The currently accepted model of cell membrane structure, depicting the membrane as a mosaic of protein molecules suspended in a fluid bilayer of phospholipid molecules

Question 9

Hypertonic Solution

Answer 9

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

Question 10

Isotonic Solution

Answer 10

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

Question 11

Marker proteins

Answer 11

Built into cell membranes, identifies cells as being one of yours

Question 12

Osmoregulation

Answer 12

The homeostatic maintenance of solute concentrations and water balance by a cell or organism

Question 13

Osmosis

Answer 13

The diffusion of free water across a selectively permeable membrane

Question 14

Passive Transport

Answer 14

The diffusion of a substance across a biological membrane, with no expenditure of energy

Question 15

Phagocytosis

Answer 15

Cellular “eating”; a type of endocytosis in which a cell engulfs macromolecules, other cells, or particles into its cytoplasm

Question 16

Phosphorylation

Answer 16

The transfer of a phosphate group, usually from ATP, to a molecule. Nearly all cellular work depends on ATP energizing other molecules by phosphorylation

Question 17

Receptor proteins

Answer 17

Built into cell membranes, receive and transmit signals into your cells

Question 18

Selective permeability

Answer 18

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

Question 19

Tonicity

Answer 19

The ability of a solution surrounding a cell to cause that cell to gain or lose water

Question 20

Transport Proteins

Answer 20

Embedded in cell membranes, move sugar molecules and other nutrients into your cells