The Circulatory System Human Body Systems Part I

One day… A man about 47 years old collapsed at work. 22 minutes of his life he does not remember. He had gone into cardiac arrest—a heart attack. Fortunately, he received treatment and lived a fairly normal life. Even ran the Boston Marathon! 1/3 of the 1.2 million Americans who suffer a heart attack or myocardial infarction (MI), die. This shows that the heart and the circulatory system are vital to life…

Circulatory Functions Transports blood, oxygen, nutrients, and other substances throughout the body Removes wastes from tissues Blood vessels of the circulatory system keeps oxygen-poor blood from mixing with oxygen-rich blood.

The Heart Structure 1. Atrium (L and R) 2. Ventricle (L and R) Upper chamber Receives blood from body 2. Ventricle (L and R) Lower chamber Pumps blood out of the heart

Blood Flow in the Heart 1. Right Atrium receives oxygen-poor blood from the body and pumps it to the… 2. Right Ventricle pumps oxygen-poor blood to the lungs.

Blood Flow in the Heart 3. Left Atrium receives oxygen-rich blood from the lungs and pumps to the… 2. Left Ventricle pumps oxygen-rich blood to all parts of the body.

Heart pumps blood through two main pathways… 1. Pulmonary circulation Occurs between the heart and the lungs. Carries oxygen-poor blood to lungs, picks up oxygen and carries back to heart. Each has a vein and artery. 2. Systemic circulation Occurs between heart and rest of body, EXCEPT lungs. Carries oxygen-rich blood to all cells and transports oxygen- poor blood back to heart.

Three types of blood vessels 1. Arteries Large vessels that carry blood from the heart to tissues of the body. Aka, “Superhighways” 2. Capillaries Smallest blood vessels. Aka, “side streets and alleys” 3. Veins After blood passes through capillaries, it returns to the heart through veins. Thinner walls than arteries Contain valves that prevent blood from flowing backwards.

Closing/Homework DUE TOMORROW INDEPENDENT WORK Workbook pages 511 and 512 all On page 511, COLOR IT