Cell Membrane

Question 0

These membrane proteins are represented by proteins that a hydrophobic domain and two hydrophilic domains

Answer 0

Transmembrane proteins

Question 1

The structure of biological membranes can best be described as?…

Answer 1

fluid mosaic of proteins interspersed in a phospholipid bilayer

Question 2

Located within the bilayer, it moderates membrane fluidity by restricting movement of phospholipid fatty acid side chains at high temperatures

Answer 2

Cholesterol

Question 3

This membrane transport molecule carries two molecules simultaneously or sequentially in opposite directions

Answer 3

Antiporters

Question 4

In 1972, what did S.J. Singer and G. Nicholson propose?

Answer 4

The fluid mosaic model

Question 5

What are the fatty acid characteristics that influence fluidity?

Answer 5

Double bonds- inhibit axial rotation and induce kinks

Long chain fatty acids pack well together and limit movement while short fatty acids create spaces into which other chains can move.

Question 6

Phospholipid bilayer is split into two leaflets- outer and inner. What’s in the outer layer?

Answer 6

Cholesterol, phosphatidylcholine, and sphingomyelin, glycolipids, glycocalyx

Question 7

Inner leaflet?

Answer 7

Cholesterol, phosphatidylethanolamine, phosphatidylserine (-charged), phosphatidylinositol (-charged, found only in inner leaflet, important in cell signaling)

Question 8

How can peripheral proteins be removed from the phospholipid bilayer?

Answer 8

By altering the pH or ionic content of the environment

Question 9

How are integral proteins removed?

Answer 9

Detergents like SDS.

Question 10

T/F membrane spanning portions of transmembrane proteins are usually alpha helices with 20-25 hydrophilic amino acids.

Answer 10

False, they are hydrophobic Amino acids

Question 11

Band 3 is an example of a transmembrane protein, the anion transporter for which ions?

Answer 11

Bicarbonate and chloride ions

Question 12

Enzyme linked receptors (receptor tyrosine kinase) and glycophorin (RBC membrane) are examples of?…

Answer 12

Single pass transmembrane proteins- single hydrophobic domain that passes through the bilipid layer only once

Question 13

Multiple pass transmembrane proteins has two or more hydrophobic domains which molecules can pass several times. How are they activated?

Answer 13

Addition of phosphate

Question 14

GLUT- glucose transporter (12)

Porin(12)

G protein linked receptors(7)

Various large transporter and channel proteins
Are examples of what?

Answer 14

Multiple pass transmembrane proteins

Question 15

What are the six types of proteins found in/on the cell membrane?

Answer 15

Channels, pumps, transporters, enzymes, receptors, structural proteins associated with tight junctions

Question 16

What are the types of movement mechanisms?

Answer 16

Diffusion, osmosis, facilitated diffusion, active transport.

Question 17

Carries two or more molecules or ions simultaneously or sequentially in the same direction

Answer 17

Symporter

Question 18

Carries one molecule or ion unidirectionally

Answer 18

Uniporter

Ex: use in facilitated diffusion

Question 19

Two types of channel complexes

Answer 19

Non gated and gated

Question 20

Responds to specific signal molecules like hormones or neurotransmitters.

Answer 20

Ligand gated channel

Question 21

Responds to change in electrical potential across the membrane.

Answer 21

Voltage gated channel

Question 22

Responds to physical change in the environment such as pressure or touch.

Answer 22

Modality gated channel

Question 23

Glycolysis is this type of respiration? Where does it occur? What does it produce?

Answer 23

Anaerobic-does not require oxygen

Occurs in the cytoplasm of all cells

Produces pyruvic acid (lactic) and 2 ATP

Question 24

Krebs cycle and ETC (electron transport chain) is this type of respiration? Occurs where? Produces?

Answer 24

Aerobic respiration

Occurs only in the mitochondria

Utilizes pyruvic acid from glycolysis, requires oxygen as the final electron receptor, produces CO2 and H2O and 34 ATP+ 2 from glycolysis=36ATP

Question 25

What are the three factors that affect diffusion?

Answer 25

Concentration differences, electrical differences, and pressure differences

Question 26

What’s V max to facilitated diffusion?

Answer 26

The rate of diffusion slows down and plateau’s when it reaches a maximum concentration of molecules diffusing in a given period.

Question 27

Potassium channels with selectivity filters and carbonyl oxygens are a type of this channel?

Answer 27

Non gated

Question 28

What are the two types of active transport?

Answer 28

Primary and secondary

Question 29

Primary active transport utilizes these transporters and derives its energy from?

Answer 29

ATPase transporter

Energy is directly derived from breakdown of ATP

Question 30

Secondary utilizes these transporters and derives energy from?

Answer 30

Multiporters (sym and anti)

Energy derived from concentration differences of ions/molecules created in primary

Question 31

Which ion is most often one of the solutes involved in secondary AT.

Answer 31

Sodium

Question 32

If sodium moves down its gradient then why is this secondary active transport?

Note: active transport moves a molecule UP (against) it’s gradient

Answer 32

Because the movement of sodium into the cell (down gradient) generates enough energy needed to transport another substance against (up) its gradient with the use of ATP.

Question 33

Sodium/calcium antiporters move three sodium ions per one calcium ion. Why?

Answer 33

Because calcium is larger and has more charge