7th Grade

Unit 5: The Structure and Function of

Body Systems

Lesson 3: Respiratory and Circulatory Systems, and Flow of Blood

Vocabulary of Instruction:

Alveoli• Tiny sacs of

lung tissue specialized for the movement of gases between the air and the blood.

Arterioles• The smallest

divisions of the arteries located between the muscular arteries and the capillaries.

Capillaries• Tiny little

venules or vessels between the arteries which carry blood from the heart and veins back to the heart.

Diaphragm• A large,

dome-shaped muscle that has an important function in breathing.

Hemoglobin• Substance in

red blood cells which conveys oxygen from the lungs to body tissues.

Platelets• Tiny

membrane-bound cell-like particles found in blood that carry materials important for the formation of clots.

Trachea• The windpipe of

the respiratory system.

Venules• The minute

vessels that collect blood from the capillary plexuses and join together to form veins.

The Whole Picture