Assignments Deadline Cannabis Final Draft Past due! Complete ASAP Endocrine Rounds Stress Log + Reflection p.695-698, questions 1-5 Red Gold (PBS) Worksheet Due end of class on Wednesday Blood Transfusion Poster

Blood The specialized fluid traveling through the cardiovascular system in arteries, veins, and capillaries Composed of formed elements and plasma

Formed Elements Erythrocytes (red blood cells) – transport respiratory gases in the blood Leukocytes (white blood cells) – defend the body against pathogens Platelets – help clot the blood and prevent blood loss from damaged vessels

Plasma Fluid portion of the blood containing proteins and dissolved solutes

Blood Functions Transportation – formed elements and dissolved ions move throughout body, “delivery system” Oxygen & carbon dioxide Nutrients from digestive system Hormones from glands Heat and waste products from cells How does medication work?

Blood Functions 2. Regulation Body temperature – absorbs heat from cells (especially skeletal muscle), heat released at surface Body pH – absorbs acids and bases from cells Fluid balance – water is gained (digestive system) and lost (urine, skin)

Blood Functions 3. Protection – leukocytes and other proteins are part of the immune system that helps protect the body against harmful substances

Characteristics of Blood Color – depends on whether it is oxygen-rich or oxygen-poor Oxygen-rich = bright red Oxygen-poor = dark red Why do our veins look blue?

Characteristics of Blood 2. Volume – average adult blood volume is 5 liters Males tend to have more blood (5-6 L) than females (4-5 L) because of larger size Appropriate blood volume is essential to maintaining blood pressure

Characteristics of Blood 3. Viscosity – blood is 4–5x thicker than water Depends on the amount of dissolved substances 4. Plasma concentration – affects diffusion/osmosis (dehydration)

Characteristics of Blood 5. Temperature – blood is about 1 degree Celsius higher than body temperature Blood warms the areas that it travels to 6. Blood pH – slightly basic (alkaline) with a pH between 7.35 and 7.45

Red Gold – The Epic Story of Blood http://www.pbs.org/wnet/redgold/ --- click on BLOOD JOURNEY