Week 11 Nutrient transport

Question 1

What is the primary function of the cell membrane?

Answer 1

Prevents entry of some substances

Retain other substances

Question 2

What are the other roles of the cell membrane?

Answer 2

Regulates rate of transport of fuel into the cell
Provides surface for attachment of proteins
Communication between extra and intra-cellular environments

Question 3

What is the cell membrane made of?

Answer 3

Phospholipids

Question 4

What is the permeability of the cell membrane?

Answer 4

Semi-permeable

Question 5

What does semi-permeable mean?

Answer 5

Allows small uncharged molecules to pass with no problem

Large molecules require transport mechanisms

Question 6

What are the two types of transport?

Answer 6

Passive and active

Question 7

What is passive transport?

Answer 7

Requires no energy other than molecules motion

Question 8

What is active transport

Answer 8

Require ATP

Question 9

What the the four types of passive transport?

Answer 9

Simple diffusion
Facilitated diffusion
Osmosis
Filtration

Question 10

What are the types of active transport?

Answer 10

Sodium-potassium pumps

Bulk transport

Question 11

What are the types of bulk transport?

Answer 11

Endocytosis
Exocytosis
Phagocytosis

Question 12

What is simple diffusion?

Answer 12

The passive movement of molecules or particles from regions of higher to lower concentration

Question 13

What is facilitated diffusion?

Answer 13

Transport of substances across a biological membrane from an area of higher concentration by means of a carrier molecule

Question 14

What does facilitated diffusion require?

Answer 14

A trans-membrane protein. (a carrier)

Question 15

What is osmosis?

Answer 15

Simple diffusion of water, rather than molecules or particles, water travels towards higher concentration of solute. The water move to maintain an equal ratio.

Question 16

What happens to the net movement of water when the water is isotonic and why?

Answer 16

There is no net movement because the solution concentration is the same

Question 17

What happens to the net movement of water when the water is hypotonic and why?

Answer 17

Net movement of water into the cell because the cell has a higher concentration than the water

Question 18

What happens to the net movement of water when the water is hypertonic and why?

Answer 18

There is a net movement of water out of the cell because the cell has a lower concentration.

Question 19

What is filtration?

Answer 19

Movement of water and solutes across the membrane due to hydrostatic pressure from the CV system. (kind of like a sieve)

Question 20

What does the sodium potassium pump do?

Answer 20

It actively transports sodium out of cells whilst simultaneously pumping potassium in to cells.

Question 21

Why is the sodium-potassium pump an active process?

Answer 21

Costs ATP as it is against the concentration gradient.

Question 22

Why do we need sodium to be removed from the muscle?

Answer 22

So when we need to contract the muscle sodium can rapidly move into the muscle cell, setting of a chain of events resulting in the muscle contracting

Question 23

What happens to the cells in endocytosis?

Answer 23

Bulk transport into the cells

Question 24

What happens to the cells in exocytosis?

Answer 24

Bulk transport out of the cell

Question 25

What is phagocytosis?

Answer 25

The ingestion of bacteria or other material by phagocytes