Cell Function

Question 1

_____ is involved in importing what is needed from the extracellular environment and exporting out what is not needed for life functions of the cell

Answer 1

Plasma membrane

Question 2

allows some substances to pass through more readily than others

Answer 2

Selective permeability

Question 3

The plasma cell membrane is ______ ______.

Answer 3

selectively permeable

Question 4

Transport across the membrane can either be ____ or ____

Answer 4

active, passive

Question 5

• Does not require any energy expenditure or “activity” of the cell membrane. - Down a concentration or electrical gradient - Requires that cell’s own kinetic energy - Diffusion

Answer 5

Passive transport

Question 6

• Requires energy expenditure of metabolic energy by the cell - Particles are “pulled” across the membrane - Usually against concentration or electrical gradient

Answer 6

Active transport

Question 7

Movement of solute down concentration or electrical gradient

Answer 7

Diffusion

Question 8

Movement of H2O through a semi-permeable membrane down concentration gradient

Answer 8

Osmosis

Question 9

Facilitated diffusion of solute through a membrane channel (may be open or closed = gated)

Answer 9

Channel-mediated transport

Question 10

Facilitated diffusion of solute through a membrane structure that changes shape

Answer 10

Carrier-mediated transport

Question 11

_____ can occur between lipid proteins and through integral proteins that function as water channels

Answer 11

Osmosis

Question 12

____ is the net movement of water from a region of high concentration to low concentration

Answer 12

Osmosis

Question 13

Water pressure that results from osmosis

Answer 13

osmotic pressure

Question 14

Osmotic pressure in the solution with higher concentration is higher… This drives the movement of ____ out

Answer 14

water

Question 15

Same relative amount of solutes in both

Answer 15

Isotonic

Question 16

higher concentration in extracellular environment

Answer 16

Hypertonic

Question 17

lower concentration in extracellular environment

Answer 17

Hypotonic

Question 18

3 qualities of channel-mediated passive transport

Answer 18

• serve as protein “tunnels” - Membrane channels are specific - allow only one type of solute to pass through - Gated channels may be open (active) or closed (inactive)

Question 19

3 qualities of carrier-mediated passive transport

Answer 19

• the carrier protein attracts and binds the solute - the carrier changes shape allowing the solute to be deposited on other side - uses a concentration gradient

Question 20

Requires the expenditure of metabolic energy by the cell - transport by pumps - transport by vesicles

Answer 20

active transport

Question 21

Membrane transporters that move a substance against its concentration gradient - opposite of diffusion

Answer 21

Transport by pumps

Question 22

_____ moves from an area of low concentration to an area of high concentration

Answer 22

Transport by pumps

Question 23

Transport by pumps are driven by 2 sources of cellular energy:

Answer 23

• Uses energy from hydrolysis of ATP - Uses energy stored in an ionic concentration gradient

Question 24

Read this to understanding everytime

Answer 24

Got it?

Question 25

Allows substances to enter or leave the interior of a cell without actually moving through its plasma membrane

Answer 25

Transport by viscles

Question 26

There are 2 types of transport by vesicles

Answer 26

1. Endocytosis-materials move into a cell
2. Exocytosis-material move out of a cell

Question 27

Process where the plasma membrane “traps” extracellular material and brings it into the cell

The cytoskeleton does all the work to form a vesicle

Answer 27

Endocytosis

Question 28

The 3 types of endocytosis

Answer 28

1. receptor-mediated endocytosis
2. phagocytosis
3. bulk phase endocytosis (pinocytosis)