Chapter 47

Circulatory and Respiratory Systems

Electrocardiogram

Lymphatic System

Structure of the Human Heart

A Closer Look atBlood Vessels

Systemic Circulation

Circulation Pathwayin the Human Body

Circulatory Loops inthe Human Body

Composition of Blood

Clotting Cascade

Blood Types

MammalianLung Structure

Respiratory System inthe Human Body

Overview of Respiration

Your heart's job is to pump blood around your body. Its muscles contract and squeeze out blood. The left-hand side pumps blood from the lungs to the rest of your body. The right-hand side pumps stale blood from your body back to your lungs for a fresh supply of oxygen.

Artery Vein

Immune SystemResponse Time

Respiratory System

Your breathing parts

You usually cannot see the air you breathe out. But on cold days the air you exhale is visible. This is because your breath contains water vapor, as well as carbon dioxide. As the water vapor meets cold air, it condenses and turns into tiny droplets of liquid water which look like white puffs of steam.

When you breathe in your chest muscles pull your ribs up and out. Your diaphragm, the muscle under your chest, moves down. Your chest expands and your lungs fill with air. When you breathe out, the muscles relax. Your ribs move down, and your diaphragm moves up to squeeze air out.

Inflammatory Response

Events of the Immune Response