Membrane Transport - Chapter 7

Question 0

What macromolecules are involved in the fluid mosaic?

Answer 0

Peripheral proteins
Transmembrane proteins
Glycolipids
Glycoproteins

Question 1

Role of cholesterol in fluidity

Answer 1

Acts as a buffer
Different effects at different temps
Body temp-restrains movement
Cool temps-maintains fluidity, prevents tight packing; useful for hibernation

Question 2

Peripheral proteins

Answer 2

Not embedded in the lipid bilayer
Bound loosely
Found attached to the membrane

Question 3

Transmembrane (integral) proteins

Answer 3

Penetrate the hydrophobic interior of the lipid bilayer

Span the entire thickness of the membrane

Question 4

Glycolipids

Answer 4

Carbohydrate attached to a lipid

Question 5

Glycoproteins

Answer 5

Carbohydrate attached to a protein

Question 6

Receptor protein

Answer 6

Receive chemical messages from other cells in the body

~like a mailbox

Question 7

Recognition protein

Answer 7

Identify the cell as a specific type

Search for foreign substances

Question 8

Transport proteins

Answer 8

Aid in transport of substances through the membrane

~ usually transmembrane

Question 9

Enzymatic proteins

Answer 9

Involved in modifying a substance through chemical reactions

Question 10

Functions of membrane carbohydrates

Answer 10

Similar jobs as proteins

• recognition
• receptor
• attach to external brand proteins to help brace it together so the membrane isn’t floppy

Question 11

Diffusion

Answer 11

The tendency of a substance to move from where they are high in concentration to where they are lower in concentration until it reaches equilibrium

Question 12

Down a concentration gradient

Against a concentration gradient

Answer 12

Down: high–>low; passive

Against: low–>high; active

Question 13

Osmosis

Answer 13

Passive transport of water down a concentration gradient across a selectively permeable membrane
Water always moves towards areas that are hypertonic

Question 14

Isotonic

• in plant cells
• in animal cells

Answer 14

Having the same concentration, no net movement

• plants become flaccid
• animals favor

Question 15

Hypertonic

• in plant cells
• in animal cells

Answer 15

External solution having more solute -plant cells plasmolyze
-animal cells crenate (shrivel)

Question 16

Hypotonic

• in plant cells
• in animal cells

Answer 16

External solution has less solute

• plants favor to become turgid
• animals burst or lyse

Question 17

Cyclosis

Answer 17

Plants in a hypotonic solution

The organelles can be seen streaming around the central vacuole

Question 18

Uniport

Answer 18

Transports one substance in one direction

Against concentration gradient

Question 19

Symport/cotransport

Answer 19

Transfers 2 substances together; one against gradient and one down a gradient

Question 20

Antiport/counter-transport

Answer 20

Transports two substances in opposite directions; both against their gradient

Question 21

Facilitated transport

Answer 21

Passive transport

Question 22

Primary active transport

Answer 22

When ATP is used directly to transport a substance

-uniport and antiport

Question 23

Secondary active transport

Answer 23

Indirect use of energy

-cotransport

Question 24

Endocytosis

Answer 24

Folding of a cell membrane around a large package of substances
Takes in a bulk package

Question 25

Exocytosis

Answer 25

Invokes the folding of the membrane around a large package of substances
Transports a bulk package outside of the cell

Question 26

Pinocytosis

Answer 26

Cells fold around an aqueous solution of dissolved substances to pull them into the cell

• “cell drinking”
• nonspecific, endocytosis

Question 27

Cell-mediated endocytosis

Answer 27

Coated with receptors to receive a certain substance

• specific
• endocytosis

Question 28

Phagocytosis

Answer 28

Take in large substances or cells

• “cell eating”
• white blood cells

Question 29

Water always moves from a solution of _____ concentration to a solution of _____ concentration

Answer 29

Higher

Lower

Question 30

Salt water is _____ compared to plain water

Plain water is _____ compared to salt water

Answer 30

Hypertonic

Hypotonic