Homeostasis during Exercise

Cardiovascular System 3 Functions in Maintaining Homeostasis Transporting substances around the body. Oxygen, glucose, carbon dioxide, and waste products Controlling body temperature. Protecting the body. Cells and antibodies that fight infections and stop bleeding

Double Circulation System Pulmonary Circuit Carries blood between the heart and lungs Deoxygenated blood passes from the right atrium into the right ventricle and then goes to the lungs.

Double Circulation System Systemic Circuit Carries blood between the heart and the rest of the body From the lungs, blood moves back toward the heart into the left atrium to the left ventricle and then passes into the aorta to go to the rest of the body

Blood Vessels Arteries carry blood away from the heart Veins carry blood toward the heart A pulse is the rhythmic stretching of the arteries caused be the pressure of blood forced into the arteries

Blood Flow through Capillary Beds Capillaries – small vessels where exchange with cells actually takes place During strenuous exercise, blood is diverted from the digestive tract and supplied more to skeletal muscles

Blood Flow through Capillary Beds Cells undergo cellular respiration to make ATP (energy) Requires O2 and produces CO2 (waste) Capillaries supply blood that carries these gases Arterial Blood = ↑ O2 ↓ CO2 Venous Blood = ↓ O2 ↑ CO2

Respiratory system 3 Steps of Gas Exchange Breathing Inhalation - O2 diffuses from air across cell lining into blood vessels Exhalation - CO2 diffuses out of blood vessels into the lungs Transport of gases by circulatory system Blood carries O2 to the rest of the body Cellular exchange of gases O2 diffuses into cells from blood CO2 diffuses out of cells into blood

Anatomy of Respiratory System

Gas Exchange in Lungs

Regulating Breathing Breathing is usually under automatic control Breathing control centers in the brain sense and respond to CO2 levels (not O2) in the blood A decrease in blood pH increases the rate and depth of breathing

Effect of Exercise When you exercise, cellular respiration increases to produce more ATP for your muscle cells This increases CO2 levels in the blood The brain senses decrease in pH due to increased CO2 levels Breathing control centers increase breathing rate and depth to eliminate CO2 in exhaled air and get more O2 in inhaled air