3a.1 - Osmosis, Gas and Solute Exchange and The Breathing System

Question 1

Define osmosis

Answer 1

The movement of water molecules across a partially permeable membrane from a region of high water concentration to an area of low water concentration

Question 2

What is a partially permeable membrane?

Answer 2

A membrane with very small holes in it

Question 3

How do water cells move in and out of cells?

Answer 3

Osmosis

Question 4

How do substances move to where they want to go in the body?

Answer 4

Diffusion, osmosis and active transport

Question 5

What is diffusion?

Answer 5

Where particles move from a high concentration to a low concentration

Question 6

Which forms of transport involves substances moving from high concentration to low concentration?

Answer 6

Diffusion and osmosis

Question 7

Which form of transport involves substances moving from low concentration to high concentration?

Answer 7

Active transport

Question 8

How are exchange surfaces adapted to maximise effectiveness? (4)

Answer 8

• Thin
• Large surface area
• Blood supply
• Ventilation

Question 9

Which part of the leaf is the exchange surface?

Answer 9

The underleaf

Question 10

Why is the underleaf the exchange surface in the leaf?

Answer 10

It is covered in small holes called stomata

Question 11

What substances diffuse out through the stomata?

Answer 11

Oxygen and water vapour

Question 12

What is the size of the stomata controlled by?

Answer 12

Guard cells

Question 13

Why are there air spaces inside the leaf?

Answer 13

Increase the surface area

Question 14

What conditions is evaporation of water vapour leaving a leaf best at?

Answer 14

Hot, dry and windy

Question 15

What is the thorax?

Answer 15

The top of the body

Question 16

Explain how gas gets to the lungs (4)

Answer 16

• Goes through the trachea
• Splits into two bronchi
• Splits into smaller bronchioles
• Ends at the alvioli

Question 17

What happens when you breath in? (4)

Answer 17

• Intercostal muscle contarcts
• Diaphragm contracts
• Volume increases
• Pressure decreases

Question 18

What happens when you breath out? (4)

Answer 18

• Intercostal muscle relaxes
• Diaphragm relaxes
• Volume decreases
• Pressure increases

Question 19

What is ventilation?

Answer 19

The movement of air into and out of the lungs

Question 20

What are advantages of the shell as a breathing aid? (3)

Answer 20

• Mimics what the body would normally do
• Stops the person from dying
• Not entirely restrictive

Question 21

What are the disadvantages of the shell as a breathing aid? (3)

Answer 21

• Heavy
• Has to stay in hospital
• Have to wear

Question 22

What are the advantages of the iron lung as a breathing aid? (3)

Answer 22

• Keeps the person from dying
• Simulates actual breathing
• Efficient

Question 23

What are the disadvantages of the iron lung as a breathing aid? (3)

Answer 23

• Bed sores from lying down a lot
• Restrictive
• Has to stay in hospital

Question 24

What are the advantages of the positive pressure systems as a breathing aid? (3)

Answer 24

• Keeps people who have no control over their lungs
• Can increase the levels of oxygen
• Can hook up different machines to test different thing

Question 25

What are the disadvantages of the positive pressure system as a breathing aid? (3)

Answer 25

• Invasive
• Has to be sedated
• Doesn’t stimulate actual breathing