B11 - Gas Exchange in humans

Question 1

What do lungs provide? [1]

Answer 1

A gas exchange surface

Question 2

What are the lungs protected by? [1]

Answer 2

The ribcage

Question 3

Where in the lungs does gas exchange happen? [1]

Answer 3

Alveoli

Question 4

What is the ribcage made up of? [2]

Answer 4

• Ribs (bone)
• Intercostal muscles

Question 5

What is the voice box called? [1]

Answer 5

Larynx

Question 6

What is the function of the LARYNX? [2]

Answer 6

Air passes through here during breathing; vocal cords are found here.

Question 7

What is the windpipe called? [1]

Answer 7

Trachea

Question 8

What is the function of the TRACHEA? [2]

Answer 8

Tube carrying air to and from the lungs.

Question 9

Why are there C shaped rings of cartilage around the trachea? [2]

Answer 9

To prevent the trachea from collapsing.

Question 10

What is the function of alveolus/alveoli? [2]

Answer 10

It is where gas exchange takes place; surrounded by capillaries.

Question 11

What are capillaries? [2]

Answer 11

Delicate blood vessels that exist throughout our bodies. They transport blood, oxygen and nutrients to cells in your organs and body systems.

Question 12

What is the function of the bronchiole? [2]

Answer 12

They are small tubes transporting air between the bronchi and the alveoli.

Question 13

What is the function of the diaphragm? [2]

Answer 13

It is a sheet of muscle below the ribcage involved in breathing/ventilation.

Question 14

What is the function of the lungs? [2]

Answer 14

They are large structures that provide the gas exchange surface.

Question 15

What is the function of the bronchi/bronchus? [2]

Answer 15

They are 2 smaller tubes transporting air between the trachea to the bronchioles.

Question 16

What is the purpose of lungs? [1]

Answer 16

To breathe

Question 17

Why do we need to breathe? [2]

Answer 17

To get oxygen in your body and carbon dioxide out.

Question 18

How do all of our cells get the energy they need to function? [1]

Answer 18

Cellular Respiration

Question 19

To carry out cellular respiration, what do you need? [1]

Answer 19

Oxygen

Question 20

What is the role of the lungs? [2]

Answer 20

To get oxygen that we need from the air all around us, into our bloodstream - where it can be transported to the rest of our body.

Question 21

What is a similarity between an alveolus and the blood capillaries right next to it? [2]

Answer 21

They both are made up of just one layer of very thin cells.

Question 22

What does one layer of thin cells increase? [2]

Answer 22

It increases the rate at which carbon dioxide and oxygen can diffuse across.

Question 23

How do alveoli have a very large surface area? [2]

Answer 23

• Adults have hundreds of millions of alveoli
• If all the alveoli were spread out flat - they would cover half a tennis court.

Question 24

Alveoli walls are ….. . What does this allow and what does this increase? [3]

Answer 24

• Moist
• Allows gases to dissolve
• Increases the rate of diffusion

Question 25

What is CO2 being carried by? [1]

Answer 25

The plasma

Question 26

What 5 things make alveoli good for gas exchange? [5]

Answer 26

1. Large Surface Area 2. Very thin 3. Moist Lining 4. Good supply of blood 5. Good ventilation

Question 27

How do alveoli have a good supply of blood? [2]

Answer 27

Each one of the alveoli has lots and lots of capillaries surrounding it.

Question 28

How do alveoli have good ventilation? [2]

Answer 28

This means good supply of air which is supplied by breathing.

Question 29

Where are oxygen and carbon dioxide exchanged? [2]

Answer 29

- The lungs - The tissues of the body

Question 30

In which direction does the oxygen exchange happen? [2]

Answer 30

Air in lungs --> blood --> tissues

Question 31

In which direction does the carbon dioxide exchange happen? [2]

Answer 31

Tissues --> blood --> air in lungs

Question 32

How do gases move across the wall of the alveolus? [1]

Answer 32

Diffusion

Question 33

What is diffusion? [3]

Answer 33

Diffusion is the net movement of particles from an area of higher concentration to an area of lower concentration as a result of random movement until an equilibrium is reached.

Question 34

What are 3 ways diffusion happens quickly? [3]

Answer 34

1. Short distance 2. Large surface area 3. Steep concentration gradient

Question 35

What is limewater used for?

Answer 35

Testing of carbon dioxide.

Question 36

What happens to limewater if there is carbon dioxide present? [2]

Answer 36

The limewater turns cloudy/milky.

Question 37

Exhaled air contains (3 things) than inhaled air. [3]

Answer 37

1. less oxygen 2. more carbon dioxide 3. a little more water vapour