Y8 Unit 1

Tiny air sacs for gaseous exchange . It looks like grape

• Alveolus

• Blood capillary

• Lung

• Trachea

Answer explanation

Tiny air sacs for gaseous exchange that look like grapes are called alveoli, making it the correct choice.

Oxygen diffuses from

• Trachea to lung

• Alveolus to blood capillary

• Blood capillary to alveolus

• Lung to trachea

Answer explanation

Oxygen diffuses from alveolus to blood capillary, where it enters the bloodstream for distribution throughout the body.

Gaseous exchange is by process of

• respiration

• diffusion

Answer explanation

Gaseous exchange occurs through the process of diffusion, where gases move from areas of high concentration to low concentration across a membrane.

Carbon dioxide diffuses from ________ to alveolus

• trachea

• lung

• blood capillary

• bronchus

Answer explanation

Carbon dioxide diffuses from blood capillary to alveolus.

Name A

• Trachea

• Lung

• Alveolus

• Blood capillary

Answer explanation

The correct choice is Blood capillary because it is the site of gas exchange between the respiratory system and the circulatory system.

Name B

• Trachea

• Lung

• Alveolus

• Blood capillary

Answer explanation

The correct answer is Alveolus, as it is the structure where gas exchange occurs in the lungs, allowing oxygen to enter the bloodstream and carbon dioxide to be removed.

Oxygen diffuses in from

• A to B

• B to A

Answer explanation

Oxygen diffuses from B to A, as it moves from an area of higher concentration (B) to an area of lower concentration (A) to reach equilibrium.

Carbon dioxide diffuses in from

• A to B

• B to A

Answer explanation

Carbon dioxide diffuses in from A to B, as indicated by the correct answer choice A to B.

Alveolus is surrounded by

_______ gas moves from the alveolus to the blood capillaries