Ch 4 - Cell Membrane Transport

Question 1

Function of the cell membrane

Answer 1

1. Barrier to separate ECF and ICF 2. Controls in and out transport

Question 2

Which types of molecules diffuse through the cell membrane easily by simple diffusion?

Answer 2

Hydrophobic Molecules -Non-polar molecules (O2, CO2, lipids) -Small polar molecule (H2O)

Question 3

Which types of molecules cannot diffuse through the cell membrane and use a transport protein?

Answer 3

Hydrophilic Molecules -Large polar molecules -Ions

Question 4

Permeability 1-4 (1 least, 4 most) CO2 / O2

Answer 4

4

Question 5

Permeability 1-4 (1 least, 4 most) H2O / Urea

Answer 5

3

Question 6

Permeability 1-4 (1 least, 4 most) Glucose

Answer 6

2

Question 7

Permeability 1-4 (1 least, 4 most) Ions

Answer 7

1

Question 8

Concentration is higher inside or outside of the cell? Na+

Answer 8

Outside

Question 9

Concentration is higher inside or outside of the cell? Ca++

Answer 9

Outside

Question 10

Concentration is higher inside or outside of the cell? K+

Answer 10

Inside

Question 11

Concentration is higher inside or outside of the cell? Cl-

Answer 11

Outside

Question 12

Concentration is higher inside or outside of the cell? Protein content

Answer 12

Inside

Question 13

Passive transport through a membrane move _____ the concentration gradient and _____ use energy

Answer 13

with does not

Question 14

Active transport through a membrane move _____ the concentration gradient and uses ______ energy

Answer 14

against does

Question 15

What are the three types of membrane transport systems?

Answer 15

Passive Active Vesicular

Question 16

Simple Diffusion Facilitated diffusion Diffusion through channels Osmosis Are all considered what types of membrane transport systems?

Answer 16

Passive Transport

Question 17

Primary active transport Secondary active transport Are all considered what types of membrane transport systems?

Answer 17

Active

Question 18

Endocytosis and Exocytosis Are considered what types of membrane transport systems?

Answer 18

Vesicular

Question 19

Phagocytosis, pinocytosis, receptor-mediated endocytosis Are considered what types of Vesicular Transport?

Answer 19

Endocytosis

Question 20

What is a second way of classifying membrane transport?

Answer 20

Simple diffusion Mediated transport

Question 21

When a transport protein is used in the mediated transport system, which are passive and which are active?

Answer 21

Passive -Carrier pump -Channel protein Active -Pump

Question 22

What are 3 types of driving forces that act on molecules?

Answer 22

Chemical Electrical Electrochemical

Question 23

Chemical Driving Force: State into or out of cell

Answer 23

Out of cell

Question 24

Chemical Driving Force: State into or out of cell

Answer 24

Into cell

Question 25

Electrical Driving Force: State into or out of cell

Answer 25

Into cell

Question 26

Electrical Driving Force

Answer 26

No force applied

Question 27

Electrical Driving Force: state into or out of cell

Answer 27

Out of cell

Question 28

Electrochemical Driving Force: state into or out of cell

Answer 28

Chemical: into Electrical: out of Chemical = Electrical Therefore; electrochemical force is in equilibrium

Question 29

Electrochemical Driving Force

Answer 29

Chemical: into Electrical: out of Chemical \< Electrical Therefore; Electrochemical will drive out of cell

Question 30

Electrochemical Driving Force: state into or out of cell

Answer 30

Chemical: into Electrical: out of Chemical \> Electrical Therefore; Electrochemical will drive Na+ into cell

Question 31

Steps to calculating Electrochemical driving force

Answer 31

1. Draw cell at equillibrium 2. draw cell at questioned parameters

Question 32

Types of Passive Transport

Answer 32

Simple diffusion Facilitated diffusion Diffusion through channels Osmosis

Question 33

Which membrane transport proteins are used for Simple Diffusion?

Answer 33

None, it is passive

Question 34

What types of substances are transported by simple diffusion?

Answer 34

hydrophobic / lipophilic molecules (O₂, CO₂, fatty acids, steroid hormones, thyroid hormones, fat soluble vitamins, some water)

Question 35

What factors affect the rate of simple diffusion?

Answer 35

1. Magnitude of the driving force 2. Membrane surface area 3. Membrane permeability

Question 36

Is there saturation during simple diffusion?

Answer 36

No

Question 37

Does a _l__arger_ or _smaller_ surface area increases simple diffusion rate?

Answer 37

Larger

Question 38

How does Facilitated Diffusion work?

Answer 38

Carrier protein binds to a molecule Protein changes shape Protein deposits molecule across membrane

Question 39

Does the transport protein in facilitated diffusion work against or with the concentration gradient?

Answer 39

With the concentration gradient

Question 40

Factors affecting rate of facilitated diffusion

Answer 40

Rate of transport of each carrier Number of carriers Concentration of molecules

Question 41

Does saturation occur during facilitated diffusion?

Answer 41

Yes

Question 42

How does diffusion through channels work?

Answer 42

Pores that are substance specific stay open to allow substance to move to lower concentration gradient

Question 43

What are the 2 types of diffusion channels?

Answer 43

Water channels Ion channels

Question 44

What types of ion channels are there?

Answer 44

Leak channels Gated channels * ligand-gated * voltage-gated

Question 45

Water moves down a concentration gradient from \_\_\_\_\_ water concentration to ____ water concentration

Answer 45

High Low

Question 46

Water moves down a concentration gradient from \_\_\_\_\_ solute concentration to ____ solute concentration

Answer 46

Low High

Question 47

Water moves down a concentration gradient from \_\_\_\_\_ osmolarity to ____ osmolarity

Answer 47

Low High

Question 48

Osmolarity is what?

Answer 48

The total concentration of solute particles in a solution

Question 49

1 molar glucose solution?

Answer 49

1 M glu x 1 particle = 1 osmol

Question 50

0.1 M NaCl solution has an osmolarity of?

Answer 50

0.1 M NaCl x 2 particles (Na⁺ & Cl^-) =0.2 osmoles