SB1i: Transporting Substances Keywords

Question 1

Active transport

Answer 1

The movement of particles across a cell membrane from a region of lower concentration to a region of higher concentration (against the concentration gradient). The process requires energy.

Question 2

Diffusion

Answer 2

When particles spread and mix with each other without anything moving them. Diffusion into and out of cells occurs for particles that are small enough to pass through the cell surface membrane.

Question 3

Concentration

Answer 3

The amount of a solute dissolved in a certain volume of solvent. Measured in units such as g/cm3.

Question 4

Concentration gradient

Answer 4

The difference between two concentrations. There will be an overall movement of particles down a concentration gradient, from higher concentration to lower concentration.

Question 5

Osmosis

Answer 5

The overall movement of solvent molecules in a solution across a partially permeable membrane, from a dilute solution to a more concentrated one.

Question 6

Passive

Answer 6

A process that does not require energy is passive. A passive process is the opposite of an active process (which requires energy).

Question 7

Semi-permeable

Answer 7

Describes something that will allow certain particles to pass through it but not others. Another term for ‘partially permeable’.

Question 8

Solute

Answer 8

The solid that has dissolved in a liquid to make a solution

Question 9

Solvent

Answer 9

The liquid in which a substance dissolves to make a solution.