Exchange And Transort In Animals

Question 1

What is the definition of diffusion?

Answer 1

The movement of molecules from an area of higher concentration to an area of lower concentration.

Question 2

In what way do particles move?

Answer 2

in both directions, but there will be a net movement from high to low concentration

Question 3

What are examples of diffusion in biological systems?

Answer 3

A leaf
In the lungs
In the liver cell

Question 4

What are multicellular organisms, surfaces and body organs are specialised for?

Answer 4

Exchanging materials

Question 5

How is the effectiveness of exchange surfaces in plants and animals is increased?

Answer 5

Large surface area
Short distance required for diffusion

Question 6

How do plants adapt to have a large surface area?

Answer 6

the flattened shape of structures such as leaves
the alveoli in the respiratory system
the villi in the digestive system.

Question 7

What is the exchange surface?

Answer 7

An area of the lungs that is adapted for efficient transfer of gases.

Question 8

What do human lungs exchange surface adapted for?

Answer 8

absorbing oxygen into the blood from the air in the lungs
transferring carbon dioxide from the blood into the lungs (which then goes into the air)

Question 9

Where are the lungs enclosed in?

Answer 9

The thorax

Question 10

What is the thorax protected by?

Answer 10

12 pairs of ribs (24 individual ribs)

Question 11

What is below the lungs?

Answer 11

Muscular diaphragm

Question 12

What are the ribs moved by?

Answer 12

2 sets of intercostal muscles

Question 13

What are the lungs sealed with?

Answer 13

two airtight pleural membranes

Question 14

What do the airtight pleural membranes do?

Answer 14

wrap around the lungs and line the rib cage

Question 15

What does the trachea branch into?

Answer 15

2 bronchi (one to each lung)

Question 16

What helps keep the trachea open as air is drawn in?

Answer 16

Rings of cartilage in the walls of the trachea

Question 17

What do bronchi split into?

Answer 17

smaller branches and then into smaller tubes called bronchioles

Question 18

What do each bronchiole end in?

Answer 18

a cluster of microscopic air sacs called alveoli

Question 19

What do the exchange of gases occurs between?

Answer 19

the alveoli and blood in the capillaries that supply the lungs.

Question 20

What does the rate of diffusion depend on?

Answer 20

Distance
Concentration difference
Surface area

Question 21

How does distance affect the rate of diffusion?

Answer 21

if the diffusion distance is small, diffusion happens faster because the particles do not have as far to travel

Question 22

How does concentration difference affect the rate of diffusion?

Answer 22

diffusion is faster if there is a big difference in the concentration between the area the substance travels from and the area that it is moving to

Question 23

How does surface area affect the rate of diffusion?

Answer 23

the larger the surface area the higher the number of particles that will be able to move in a given time so the faster the rate

Question 24

What is flicks law?

Answer 24

describes the relationship between the rate of diffusion and the three factors that affect diffusion

Question 25

What does flicks law state?

Answer 25

‘the rate of diffusion is proportional to both the surface area and concentration difference and is inversely proportional to the thickness of the membrane’.

Question 26

What Is the equation for flicks law?

Answer 26

Rate of diffusion is proportional to: (surface area x concentration difference) / thickness of membrane