Upload
maryann-watkins
View
219
Download
0
Embed Size (px)
DESCRIPTION
Types of Blood Vessels Arteries –Carry blood away from the heart –Have thick, muscular walls –Branch out into arterioles –Largest artery = Aorta
Citation preview
Components of Blood
Circulatory System
Circulation
Types of Blood Vessels• Arteries
– Carry blood away from the heart– Have thick, muscular walls– Branch out into arterioles– Largest artery = Aorta
• Veins (Contain valves – prevent backflow)– Carry blood back to the heart– Have thinner walls (less muscle)– Veins branch out into venules– Largest vein = Vena Cava
• Capillaries– Connect arterioles to venules– Extremely thin walls (allow oxygen & carbon
dioxide to pass through)
Components of Blood1. Red blood cells (RBC)2. White blood cells (WBC)3. Plasma4. Platelets (Thrombocytes)
• Plasma– Made of mostly water– Transports nutrients, hormones, proteins,
salts, & enzymes– Suspends solid components of blood
Types of Blood Cells• Erythrocytes
– RBCs– Carry oxygen to body cells / Return carbon
dioxide to the lungs– Contain hemoglobin
• Heme = Iron compound• Globin = Protein molecule
• Leukocytes– WBCs– Fight infection– 5 types of WBC
• Thrombocytes– Known as platelets– Purpose is to clot RBC together
– When a vessel is cut, platelets collect @ the site to form a sticky plug (then form scab)
Platelets
Types of WBC
Neutrophils• Most numerous• Destroy bacteria
(surround & consume = phagocytosis)
Eosinophils• Destroy parasites
(release toxin to kill)• Defends against allergic
reactions
Basophils• Produce histamine;
participates in body’s inflammatory response
Monocytes• Destroy bacteria &
foreign materials (dead cells)
• Largest type of WBC
Lymphocytes (Special type)• Can multiply in tissues of
tonsils, spleen, lymph nodes
• T-Cells (Helper T / Killer T) & B –Cells (create antibodies)
• T and B Cells fight viruses
• Protect against cancer cells
Circulation Facts• About 4 to 6 quarts of blood in the average
adult.• Heart circulates the body’s blood supply
about 1,000 times each day.• At age 70, the heart has beat about 2 ½
billion times.• Plasma is 90% water• RBC / WBC / Platelets are made in the
bone marrow