Module 18: Membrane Transport

Question 1

What is Brownian motion?

Answer 1

Constant, random movement of molecules.

Question 2

How does molecular size and temperature affect Brownian motion?

Answer 2

1. The smaller the molecule the more Brownian motion.

2. As temperature increases we get more molecular movement.

Question 3

T/F Molecules are constantly in motion?

Answer 3

True

Question 4

Active transport?

Answer 4

Allows movement from low to high concentration. Energy is to be required ATP

Question 5

Passive Transport?

Answer 5

Diffusion moves from high to low concentration. No energy required (Could be a source of Energy).

Question 6

Define diffusion?

Answer 6

Molecules move from areas of high concentration to low concentration.

Question 7

What is Osmosis?

Answer 7

The diffusion of water across a selectively permeable membrane.

Question 8

What happens during Selectively permeable?

Answer 8

Water can freely pass across membrane but Dissolved substances cannot.

Question 9

For diffusion Directly across the cell membrane what must be needed?

Answer 9

Molecules must be non-polar; O2 gas, hormones(lipid-soluble), & Drugs (Nicotine)

Question 10

Diffusion of Polar molecules or ions requires?

Answer 10

Requires Protein channel (Facilitated Diffusion)

Question 11

What are hypertonic solutions?

Answer 11

The solution with the higher concentration of solute is hypertonic.

Question 12

What are hypotonic solutions?

Answer 12

The solution with the lower concentration of solutes is hypotonic.

Question 13

What are isotonic solutions?

Answer 13

If the osmatic concentration of two solutions are equal the solutions are isotonic.

Question 14

Uniport?

Answer 14

One molecule is transported across membrane.

Question 15

What are the two Co-Transport?

Answer 15

1. Symport-2 molecules pass membrane in same direction

2. Antiport-2 molecules pass across membrane in opposite direction.

Question 16

How does water enter and exit cells? What type of transport is this?

Answer 16

Aquaporins and it is passive transport

Question 17

What does it mean Membrane Protein are gated?

Answer 17

can be found in an open or closed state; only under certain circumstances will they allow things to pass across the membrane. If the cell receives a signal, such as acetylcholine from neurons that control muscle contraction, gated channels open in response, leading to a muscle contraction.