Unit 1 1.2 Transport Across Membrane

Question 1

All living things have a

Answer 1

Membrane

Question 2

The membrane has constantly mobile phospholipid (fat) molecules with proteins embedded in a??

Answer 2

Mosaic pattern.

Question 3

The cell membrane contains?

Answer 3

Phospholipid molecules, arranged in a double layer. This layer is constantly moving, allowing the cell to change shape.

Question 4

A patchy mosaic of protein molecules is??

Answer 4

Pores in the proteins form channels

Question 5

The membrane is made of??

Answer 5

protein and phospholipids.

Question 6

If protein or phospholipids become damaged, the so does the

Answer 6

Membrane

Question 7

Proteins become damaged at???

Answer 7

high temperatures.

Question 8

Phospholipids are soluble in

Answer 8

Alcohol

Question 9

The membrane contains proteins that have channels, which allows

Answer 9

molecules to move into and out of the cell.

Question 10

Small molecules can pass through slowly, larger molecules must ….

Answer 10

First be broken down.

Question 11

A concentration gradient is the difference in

Answer 11

concentration between two solutions.

Question 12

Passive transport is the movement of a substance _________ a concentration gradient.

Answer 12

Passive transport is the movement of a substance Passive transport is the movement of a substance DOWN a concentration gradient. a concentration gradient.

Question 13

This does not require ____________.

Answer 13

This does not require ENERGY

Question 14

Diffusion is the name given to the movement of molecules of a

Answer 14

substance

Question 15

Diffusion is the movement of molecules ___________ a concentration gradient from a __________concentration to a __________ concentration

Answer 15

Diffusion is the movement of molecules DOWN a concentration gradient from a HIGHER concentration to a LOWER concentration

Question 16

Molecules that move by diffusion do not require ________________ to move. For this reason diffusion is an example of ________________ transport

Answer 16

Molecules that move by diffusion do not require ENERGY to move. For this reason diffusion is an example of PASSIVE transport

Question 17

Diffusion is used by

Answer 17

cells to move useful substances into cells and waste products out.

Question 18

Osmosis is the special name given to the diffusion of water. Like diffusion, osmosis is also a passive process, so does not

Answer 18

require energy.

Question 19

Cells can gain or lose water by ______________, depending on the ______________ concentration of the solution inside the cell compared to water concentration of the solution _______________ the cell.

Answer 19

Cells can gain or lose water by OSMOSIS, depending on the WATER concentration of the solution inside the cell compared to water concentration of the solution OUTSIDE the cell.

Question 20

Osmosis is the movement of water molecules from a _____________ water concentration to a _____________ water concentration through a __________ permeable membrane

Answer 20

Osmosis is the movement of water molecules from a HIGHER water concentration to a LOWER water concentration through a SELECTIVELY permeable membrane

Question 21

When a plant cell is placed in pure water it swells up due to water diffusing in and filling the vacuole, the word to describe this is?.

Answer 21

TURGID

Question 22

When a plant cell is left in a strong sugar solution the water diffuses out, causing the cell contents to shrink away from the cell wall. This cell is now described as being

Answer 22

Plasmolysed

Question 23

Active transport is the movement of molecules or ions from a region of ___________ concentration to a region of higher concentration _____________ a concentration gradient

Answer 23

Active transport is the movement of molecules or ions from a region of LOWER concentration to a region of higher concentration AGAINST a concentration gradient

Question 24

As this process works against the concentration gradient it requires _______________. Membrane proteins use this energy to move the molecules or ions.

Answer 24

As this process works against the concentration gradient it requires ENERGY Membrane proteins use this energy to move the molecules or ions.

Question 25

An example of active transport in the human body occurs in???

Answer 25

nerve cells