Lecture 3

Question 1

what is the plasma membrane also called

Answer 1

fluid mosaic model

Question 2

what’s the must abundant lipid in the plasma membrane

Answer 2

phospholipid

Question 3

where do phospholipids move in the plasma membrane?

Answer 3

within the bilayer

Question 4

what are flippase and floppase

Answer 4

enzymes that move things between the two inlets

Question 5

what does flip flop signify and how often does it happen

Answer 5

tells other cells that it is dying and is ready to be digested, 1 a month

Question 6

are membranes rich in unsaturated fatty acid or saturated fatty acid more fluid

Answer 6

unsaturated

Question 7

when cholesterol is in a warm temperature, what happens?

Answer 7

it restrains the movement of phospholipids

Question 8

what is a membrane?

Answer 8

a collage of different proteins embedded in the fluid matrix of the lipid bilayer

Question 9

what are the six major functions of membrane proteins ?

Answer 9

Transport
enzymatic activity
signal transduction
cell-cell recognition
intercellular joining
attachment to the cytoskeleton and ECM

Question 10

Passive transport ?

Answer 10

diffusion
facilitated diffusion

Question 11

why is facilitated diffusion passive?

Answer 11

even though it needs a transporter protein present, it is still going from a high concentration to a low concentration gradient

Question 12

Active transport?

Answer 12

Primary and secondary

Question 13

what are the three types of movement across membranes?

Answer 13

passive transport
active transport
exocytosis and endocytosis

Question 14

what is diffusion

Answer 14

tendency for molecules to spread out evenly into available space. substance moves down the concentration gradient.

Question 15

Osmosis is what gradient

Answer 15

low to high

Question 16

what is osmosis

Answer 16

the diffusion of water across a selectively permeable membrane

Question 17

what is tonicity

Answer 17

the ability of a solution to cause a cell to gain or lose water

Question 18

What do channel proteins do in facilitated diffusion

Answer 18

provide corridors that allow specific molecules or ion to cross the membrane

Question 19

what does a carrier protein do in facilitated diffusion

Answer 19

they change shape subtly that translocates the solute binding site across the membrane

Question 20

what are microtubules made of?

Answer 20

protein called tubulin, dynein, kinesin

Question 21

What energy is used in active transport?

Answer 21

ATP

Question 22

what cell is the sodium potassium pump in? is it active or passive transport

Answer 22

animal cells, active transport

Question 23

how many sodium and how many potassium go through a sodium potassium pump

Answer 23

3 Na and 2 K

Question 24

what are the three classes of transporters for active transport

Answer 24

uniport
symport
antiport

Question 25

where does primary active transport get its energy

Answer 25

directly from the breakdown of ATP

Question 26

what does secondary active transport use

Answer 26

the electrochemical gradient that was created by the primary active transport

Question 27

what is exocytosis and endocytosis

Answer 27

Bulk transport

Question 28

what are the three types of endocytosis

Answer 28

phagocytosis
pinocytosis
receptor mediated endocytosis

Question 29

what is a food vacuole called (phagocytosis)

Answer 29

Phagosome

Question 30

does endocytosis increase the cells surface area

Answer 30

no

Question 31

does exocytosis increase the cells surface area

Answer 31

yes