Grade 8 Science Quiz: Ventilation

What happens to the diaphragm during inhalation?

• It relaxes and moves up

• It contracts and moves down

• It disappears

• It inflates like a balloon

Which muscles lift the rib cage during inhalation?

• Biceps

• Intercostal muscles

• Heart muscles

• Neck muscles

What happens to the chest volume during inhalation?

• It decreases

• It stays the same

• It increases

• It bursts

Why does air flow into the lungs during inhalation?

• Because chest pressure is high

• Because the diaphragm pushes it

• Because pressure inside the chest drops

• Because oxygen is heavy

What happens to the diaphragm during exhalation?

• It contracts and moves down

• It relaxes and moves up

• It fills with air

• It becomes soft

What is ventilation?

• The process of digesting food

• The process of filtering blood

• The process of breathing in and out

• The movement of bones

What are alveoli?

• Bones in the rib cage

• Tiny air sacs where gas exchange happens

• Muscles in the chest

• Tubes that carry food

What happens in the alveoli?

• Oxygen leaves the body

• Food is broken down

• Oxygen enters the blood and carbon dioxide leaves

• Blood is pumped by the heart

During exhalation, what happens to chest volume?

• It increases

• It gets filled with oxygen

• It decreases

• It stays the same

Why do you breathe faster after running?

• To cool your body

• To bring more oxygen for energy and remove carbon dioxide

• To make your lungs stronger

• To make you tired