The Circulatory System Mary Ronchetti, Elizabeth Hein, Brandon Harris

Function Sends Oxygen and food throughout the body Takes wastes and carbon dioxide out of the body Sends hormones throughout the body

Blood Blood is made up of: Plasma: mostly water, serves as a transport medium and a solvent for ions and molecules Red Blood Cells: Biconcave disks, transport oxygen used in aerobic respiration and carry away some carbon dioxide waste. White Blood Cells: function in defense and removing unwanted molecules/cells Platelets: release substances that initiate blood clotting

The Heart 2 atria meet at the top of the heart 2 ventricles are at the bottom of the heart A septum divides the left and right sides of the heart The heart is a muscle that contracts and expands to "pump" blood through the chambers into the vessels

The Pulmonary Circuit and The Systemic Circuit Arteries bring blood from the heart to the lungs Veins bring blood from the lungs back to the heart

Pulmonary Circuit The heart is divided into 2 pumps that work together to circulate blood The right half pumps oxygen-poor blood through arteries Arteries bring blood to capillaries in the lungs, where blood is oxygenated in exchange for carbon dioxide Oxygenated blood then moves to the left half of the heart

Systemic Circuit The left half of the heart pumps freshly oxygenated blood through veins Veins pump blood to capillaries tissues and organs that need oxygen in the body The oxygen-poor blood returns to the right pump

Blood Vessels 3 main types of blood vessels o Arteries o Veins o Capillaries

Structure of Arteries Are thick, contains many layers of elastic tissue to prevent from being cut or bursting Arteries have a thick soft muscle to help the movement of blood (pulse) and prevent the pulse from bursting the artery

Structure of Veins Veins have a thin soft muscle and have valves to ensure blood always moves towards heart Veins are wider than arteries, act as storage for blood o large-diameter means higher velocity Valves in the veins prevent backflow

Structure of Capillaries Single cell endothelial cell lining to allow oxygen and carbon dioxide, as well as nutrients to easily diffuse in and out Abundant so cells have easy access

Structure of Blood Vessels Artery Vein Capillary

Gas Exchange Blood cells squeeze through capillaries Oxygen, carbon dioxide, and other small nonpolar substances pass through the lipid section of the capillary walls Proteins enter and exit the capillary wall through endocytosis and exocytosis White blood cells and small water-soluble substances pass through the clefts in between endothelial cells of capillary wall Ultrafiltration: protein-free plasma is pushed out of the capillaries through the clefts between endothelial cells because the outward-directed force is stronger than the inward-directed force Reabsorption: when the inward-directed force exceeds the outward-directed force and tissue fluids move into the capillary gas exchange won't happen if the

Gas Exchange in Capillaries Inward-Directed Flow Bulk Flow Blood From Arteriole

Animation AMo

Bibliography Starr, Cecie, and Ralph Taggart. Biology: The Unity and Diversity of Life. United States of America:Brooks/Cole, Argyle, B. "Blood Gases." Mad Scientist. Mad Scientist, Web. 6 Nov Blood Vessels. BBC, Web. 3 Nov < gcsebitesize/pe/appliedanatomy/0_anatomy_circulatorysys_rev3.shtml>. SUNY. "Circulatory System." Circulatory System. SUNY, n.d. Web. 6 Nov < bio%20102%20lectures/circulatory%20system/circulat.htm>.