Movement through cell membranes

Question 1

Cell membranes are

Answer 1

Semi permeable

Question 2

Diffusion

Answer 2

The movement of substances from an area of high concentration to an area of low concentration

Question 3

Diffusion takes place along a

Answer 3

Concentration gradient

Question 4

Example of diffusion in plants

Answer 4

Carbon dioxide diffusion into a leaf and oxygen diffusion out of a leaf through the stomata

Question 5

Example of diffusion in humans

Answer 5

Oxygen diffusion from the alveoli of the lungs into the blood and carbon dioxide diffusing out of the blood into the alveoli

Question 6

Osmosis

Answer 6

The diffusion of water molecules across a semi-permeable membrane from a region of high water concentration to a region of low water concentration

Question 7

Does osmosis require energy

Answer 7

No it’s passive

Question 8

Does diffusion require energy

Answer 8

No it’s a passive process

Question 9

Osmosis is a

Answer 9

Special type of diffusion

Question 10

Solvent

Answer 10

A liquid that dissolves other substances eg. water

Question 11

Solute

Answer 11

A substance that has been dissolved eg. Salt dissolved in water

Question 12

Solution

Answer 12

The mixture of solvent and the solute eg. Salty water

Question 13

Salty water

Answer 13

Solution

Question 14

Water

Answer 14

Solvent

Question 15

Salt

Answer 15

Solute

Question 16

Animal cell membranes are …

Answer 16

Semi permeable

Question 17

Water can move in and out of cell by osmosis depending on

Answer 17

The water concentration in the cell compare to its external environment

Question 18

If a cell is surrounded by a solution with a higher water concentration
And what will happen

Answer 18

Water will move into the cell by osmosis and it will swell up

Question 19

If a cell is surrounded by a solution with the same water content concentration

Answer 19

Osmosis will not occur

Question 20

If a cell is surrounded by a solution with lower concentration of water

Answer 20

Water will pass out of the cell by osmosis and the cell will shrink

Question 21

Plant cell membrane

Answer 21

Semi-permeable

Question 22

Cell wall is

Answer 22

Fully permeable

Question 23

Turgid or turgid pressure

Answer 23

The pressure of the cytoplasm and vacuole against the cell wall of a plant

Question 24

If an plant cell is surrounded by a solution with a higher water concentration (long

Answer 24

Water will pass out of the cell by osmosis
Cytoplasm and vacuole swell and push out on cell wall
Wall becomes stretched and rigid
Cell is very firm -turgid

Question 25

What is turgid important for

Answer 25

Gives support in plants

Question 26

By doesn’t a plant cell burst instead of becoming turgid

Answer 26

It’s cell wall prevents that

Question 27

Plasmolysis

Answer 27

The shrinkage or the cell content due to loss of water by osmosis

Question 28

If a plant cell is surrounded by a solution of the same water content

Answer 28

Osmosis will not occur

Question 29

If a plant cell is surrounded by a solution with a lower water concentration (long)

Answer 29

Water will move out of the cell by osmosis Vacuole shrinks Membrane comes away from cell wall Cell is plasmolysed and flaccid

Question 30

How is plasmolysis reversible

Answer 30

Placing the plant in water as water will enter the cells by osmosis

Question 31

What happens to a plasmolised plant?

Answer 31

It wilts

Question 32

How is food preservation osmosis

Answer 32

Food soaked in salty solutions (or sugar) Water out of microorganisms cells into food Cells become plasmolised Prevents their growth

Question 33

2 plant examples of osmosis

Answer 33

Absorption of water by plant root epidermal cells | Absorption of water by germinating seeds

Question 34

2 animal examples of osmosis

Answer 34

Absorption of water in the intestine | Re absorbtion of water in the kidney tubule (nephron)

Question 35

Osmoregulation

Answer 35

The maintenance of water and sat balance in body fluids

Question 36

Human osmoregulation example

Answer 36

Kidneys ate osmoregulation you organs

Question 37

Non human example of osmoregulation

Answer 37

In amoeba the contractile vacuoles regulate the water balance

Question 38

Phagocytosis

Answer 38

The process by which large particles are engulfed (eaten) by the cell and become incorporated into a vacuole within the cell

Question 39

Example of phagocytosis

Answer 39

Feeding in amoeba by pseudopods | Food into food vacuole

Question 40

Active transport

Answer 40

The movement of a substance from an area of lower concentration to an area of higher concentration

Question 41

How is active transport different to diffusion (2)

Answer 41

Against a concentration gradient. | Requires energy.

Question 42

Where does the energy for active transport come from

Answer 42

In the form of ATP generated inside the mitochondria

Question 43

Example of active transport in plants

Answer 43

Absorption of minerals eg.magnesium by root epidermal cells

Question 44

Example of active transport in animals

Answer 44

Reabsorption of saltine the nephron of the kidneys

Question 45

How do plant cells remain turgid fora considerable period of time

Answer 45

Keep absorbing water

Question 46

Water enters the outermost cells of the root by diffusion, what does this tell you about the cell shape of these cells?

Answer 46

Lower water concentration than soil

Question 47

Why is osmosis a special type of diffusion

Answer 47

Still movement of substance from high concentration to low concentration - just specific to water