The process of breathing

Question 1

Trachea

Answer 1

This is also called the windpipe. This tube runs from the mouth, down the throat towards the lungs. It is lined with rings of cartilage which keep it open at all times.

Question 2

Bronchus

Answer 2

The trachea splits into two bronchi, each leads to a lung. (Plural: ‘bronchi’.)

Question 3

Bronchiole

Answer 3

Each bronchus splits again and again into thousands of smaller tubes called bronchioles which take the air deeper into the lungs.

Question 4

Alveolus

Answer 4

At the ends of bronchioles are tiny air sacs called alveoli. (Singular: ‘alveolus’.) Here oxygen moves into the blood and carbon dioxide moves out.

Question 5

Intercostal muscles

Answer 5

These muscles run between the ribs and form the chest wall. They contract and relax with the diaphragm when a person breathes.

Question 6

Diaphragm

Answer 6

The diaphragm is a dome-shaped, flat sheet of muscle under the lungs. It contracts and relaxes with the intercostal muscles during breathing.

Question 7

What are the rings around your trachea made from?

Answer 7

CARTILAGE

Cartilage is a firm, elastic support substance: rings of it surround the trachea to keep it open.

Question 8

What does the trachea directly split into?

Answer 8

BRONCHI

The trachea splits into the two bronchi.

Question 9

What moves into the blood in the lungs?

Answer 9

OXYGEN

Blood picks up oxygen as it passes through the lungs.

Question 10

What are the muscles between the ribs called?

Answer 10

INTERCOSTAL

The muscles between the ribs are called intercostal muscles (inter means between).

Question 11

What process in cells requires oxygen to release energy?

Answer 11

RESPIRATION

Respiration uses oxygen in order to release energy from glucose.

Question 12

What is the scientific name for breathing in?

Answer 12

INHALATION

Inhalation is the name of breathing in - it starts with “in”, which can help you remember.

Question 13

True or false? The intercostal muscles alone contract and relax to help breathing.

Answer 13

FALSE
The diaphragm and intercostal muscles all contract and relax as part of breathing. They work hardest when breathing is fast, during exercise for example.

Question 14

Which of these happens during breathing out?

Answer 14

Both the diaphragm and the intercostal muscles relax during exhalation.

Question 15

True or false? The area of an adult’s lung is about the size of a tennis court.

Answer 15

TRUE. The surface area of a healthy adult lung is roughly the size of a tennis court.

Question 16

Name some features of the alveoli?

Answer 16

Millions of tiny blood vessels called capillaries
Moist, thin walls to maximise diffusion
A huge combined surface area