Unit 3 - Cell Transport (etc)

Question 1

What are the lipids responsible for in the plasma membrane? How about the proteins?

Answer 1

Lipids= isolating function
Proteins= transport + communication

Question 2

What are the 3 categories of membrane proteins?

Answer 2

1. Transport Proteins
2. Receptor Proteins
3. Recognition Proteins

Question 3

What do transport proteins do?

Answer 3

Regulate the movement of hydrophobic substances

Question 4

What are the two types of transport proteins?

Answer 4

Channel proteins + carrier proteins

Question 5

Channel Proteins

Answer 5

Type of transport protein. Form pores which transport according to size + charge

Question 6

Carrier Proteins

Answer 6

Type of transport protein. Have binding sites where specific substances attach in order to be transported.

Question 7

What do receptor proteins do?

Answer 7

Cause cellular respiration when specific molecules attach. Some act as gates on channel proteins.

Question 8

What do recognition proteins do?

Answer 8

Act as I.D. tags on the cell structure and function in immune response. (Most are glycoproteins)

Question 9

Cell membranes are ______ permeable. What does this mean?

Answer 9

Selectively permeable. It means that some substances can cross, others cannot. It is also much more selective than semi-permeable / permeable structures.

Question 10

What are the two types of transport stuff uses to get across the cell membrane?

Answer 10

1. Passive Transport

2. Energy-Required (Active) Transport

Question 11

Passive transport does what? (concerning conc. gradient and energy)

Answer 11

Follows the concentration gradient (high to low) and does not require energy.

Question 12

Active transport does what? (concerning conc. gradient and energy)

Answer 12

Functions regardless of concentration gradient and requires a gateway and energy (ATP)
(EX. sodium/potassium pump)

Question 13

What are the 3 processes that use passive transport?

Answer 13

Diffusion, osmosis, and facilitated transport

Question 14

What are the 3 processes that use active transport?

Answer 14

Active transport, exocytosis, and endocytosis.

Question 15

What are the 3 principles of diffusion?

Answer 15

1. Diffusion is the net movement of molecules down the concentration gradient (high to low)
2. Does not move molecules rapidly or over long distances
3. If no other process is involved, it will continue until equilibrium is reached.

Question 16

What two substances can pass the cell membrane freely?

Answer 16

Oxygen gas (O2) and Carbon Dioxide (CO2)

Question 17

What 5 things is rate of diffusion dependent on?

Answer 17

1. Concentration gradient
2. Size + shape of molecules
3. Temperature
4. Concentration (total # of molecules)
5. Chemical properties

Question 18

Which substances can diffuse through the phospholipid bilayer?

Answer 18

small lipid soluble molecules (ex. gases, ALCOHOL, etc.)

Question 19

What is osmosis?

Answer 19

The diffusion of water from high to low concentration across the membrane through a pore.

Question 20

What force causes the diffusion of water through a membrane (aka Osmosis)?

Answer 20

Osmotic Pressure

Question 21

What is Hydrostatic Pressure?

Answer 21

The force created by the mass of water accumulating in the area of lower concentration (counterbalances osmotic pressure)

Question 22

What does it mean when an environment is Hypotonic?

Answer 22

It is less concentrated than the cell (more water is present) so the cell gains water.

Question 23

What does it mean when an environment is Hypertonic?

Answer 23

It is more concentrated than the cell (less water is present) so the cell loses water.

Question 24

What does it mean when an environment is Isotonic?

Answer 24

Environment is equal to concentration of cell so no water is gained/lost.

Question 25

Animal/Plant cell that is placed in a hypotonic solution (more water present than cell) will undergo ____/_____

Answer 25

Cytolysis in animal cells

Turgo Pressure in plant cells

Question 26

Animal/Plant cell that is placed in a hypertonic solution (less water present than cell) will undergo ____/____

Answer 26

Crenation in animal cells

Plasmolysis in plant cells

Question 27

What is another way to say Passive Transport?

Answer 27

Facilitated Transport

Question 28

What is endo/exo-cytosis?

Answer 28

Cell eating(endocytosis) and pooping(exocytosis). An energy (ATP) required active process for moving large substances or large amount of substances in and out of the cell.