Exchanging Substances

Question 1

Define Duffusion?

Answer 1

> Movement of particles from area of high concentration -> low concentration
Down a concentration gradient
Until equilibrium

Question 2

What type of process is diffusion?

Answer 2

Passive process

No energy required

Question 3

What factors affect rate of diffusion?

3

Answer 3

> Temperature

> Surface area

> Concentration Gradient

Question 4

What happens to rate of diffusion when you increase temperature?

Answer 4

Increases -> particles move faster due to heat energy transferred to kinetic Energy

Question 5

What happens to rate of diffusion when surface area increases?

Answer 5

Increase -> particles have to spread out further over a larger space

Question 6

What happens to rate of diffusion when concentration gradient increases?

Answer 6

Increases -> More spreading of particles to other side to reach equilibrium

Question 7

Define Osmosis?

Answer 7

Movement of water molecules from a dilute to a concentrated solution through a partially permeable membrane

Question 8

What is a dilute solution?

Answer 8

Low concentration of solute (sugar)

High concentration of solvent (water)

HYPOTONIC SOLUTION

Question 9

What is a concentrated solution?

Answer 9

High concentration of solute (sugar)

Low concentration of solvent (water)

HYPERTONIC

Question 10

What is a dilute solution known as?

Answer 10

HYPOTONIC

Question 11

What is a concentrated solution known as?

Answer 11

HYPERTONIC

Question 12

What is an Isotonic solution?

Answer 12

Solution that has same salt concentration as cells and blood

Question 13

Define Active Transport?

Answer 13

> Movement of substances from low concentration-> high concentration
Against a concentration gradient

Question 14

What type of process is active process?

Answer 14

Energy requiring

Question 15

Example of Active Transport in plant?

Answer 15

Root Hair Cell:

> Minerals from soil

Question 16

Example of Active Transport in Animals?

Answer 16

Intestines:

> Sugar in intestine into blood

> Gluscose for respiration

Question 17

What is meant by semi-permeable?

Answer 17

Allows some substances to pass through but not all

Question 18

What organisms need exchange surfaces?

Answer 18

Multi cellular

Large

Question 19

What is surface area?

Answer 19

Area of surface of something

Question 20

What is volume?

Answer 20

Amount of space and object occupies

Question 21

How to calculate volume?

Answer 21

Length × Width × Height

Question 22

How to calculate Surface Area?

Answer 22

Length × Length

Question 23

How to calculate

Surface area : Volume?

Answer 23

SA : V = SA
——-
V

Question 24

Bigger SA : V means…..

Answer 24

Diffusion occurs quickest

Question 25

How is Alveoli (Lungs) adapted to diffusion efficiently?

Answer 25

> Thin walls -> Short diffusion pathway > Millions -> Bigger SA > Capillaries surrounding -> Maintain conc gradient

Question 26

How is small intestine adapted to diffusion?

Answer 26

Villi = Large SA One cell thick = Short diffusion pathway Close to blood = Maintain concentration gradient

Question 27

How are fish gills adapted to diffusion?

Answer 27

Lots of Gill filaments = Large SA Blood with 02 + CO2 = Maintain concentration gradient

Question 28

How are Roots adapted to diffusion? | Plant

Answer 28

Large extensions = Large SA Large vacuole = Maintain concentration gradient Thin wall = Short diffusion pathway

Question 29

How is the leaf adapted to diffusion? | Plant

Answer 29

Elongated cells = Large SA Lots of chloroplasts = Large SA for photosynthesis Air spaces between cells = Decrease diffusion pathway

Question 30

How does a large SA increase diffusion?

Answer 30

More surface area for substances to pass

Question 31

How does a thin cell membrane / wall help diffusion?

Answer 31

Shorter diffusion pathway

Question 32

How does efficient bloody supply help diffusion? | Good capillary network

Answer 32

Maintains concentration gradient