Science year 8_1.2 Gas exchange

In a gas, the particles are usually in what state?

• Close to each other

• Touching each other

• Far apart from each other

• Stuck together

How do particles move in a gas?

• Move freely

• Vibrate in place

• Do not move

• Only move up and down

What are the small holes in the lungs called?

• Blood cells

• Capillaries

• Alveoli

• Skin cells

What are the characteristics of blood vessels in the lungs?

• Thick and hard

• Thin and soft

• Thick and soft

• Thin and hard

What is the function of the alveoli?

• Store blood

• Gas exchange

• Digest food

• Protect the body

How many layers of cells make up the walls of the alveoli?

• Two layers

• Three layers

• One layer

• Four layers

What is the process of gas exchange in the air sacs called?

• Respiration

• Gas exchange

• Diffusion

• Dissolution

How many layers of cells does oxygen from the air pass through to enter the blood?

• One layer

• Two layers

• Three layers

• Four layers

When oxygen enters the blood, it combines with which substance in red blood cells?

• Hemoglobin

• Glucose

• Protein

• Lipid

The process of oxygen moving from an area of high concentration to an area of low concentration is called what?

• Dissolution

• Diffusion

• Respiration

• Filtration