Blood The only fluid tissue in the human body Classified as a connective tissue
Blood If blood is centrifuged Erythrocytes sink to the bottom Buffy coat contains leukocytes and platelets Buffy coat is a thin, whitish layer between the erythrocytes and plasma Plasma rises to the top
Blood Figure 10.1 (1 of 2)
Blood Figure 10.1 (2 of 2)
Physical Characteristics of Blood Sticky opaque fluid with characteristic metallic taste In a healthy man, blood volume is about 5 6 liters or about 6 quarts
Blood Plasma Composed of approximately 90% water; straw colored Over 100 different dissolved substances Nutrients Salts Respiratory gases Hormones Plasma proteins Waste products
Blood Plasma Plasma proteins Various plasma proteins include Albumin regulates osmotic pressure Clotting factors and fibrinogen help to stem blood loss when a blood vessel is injured Antibodies help protect the body from pathogens
Review Questions 1 1. What is the only tissue fluid in the body? 2. Why is blood considered a connective tissue? 3. What is your buffy coat made up of? 4. Name some physical characteristics of blood. 5. What is plasma made up of? 6. Name three different types of plasma proteins.
Formed Elements Erythrocytes - Red blood cells (RBCs) Leukocytes - White blood cells (WBCs) Platelets - Cell fragments
Photomicrograph of a Blood Smear Figure 10.2
Characteristics of Formed Elements of the Blood Table 10.2 (1 of 2)
Characteristics of Formed Elements of the Blood Table 10.2 (2 of 2)
Formed Elements Erythrocytes (red blood cells or RBCs) - Main function is to carry oxygen Anatomy of circulating erythrocytes Biconcave disks Essentially bags of hemoglobin Anucleate (no nucleus) Contain very few organelles 5 million RBCs per cubic millimeter of blood
Formed Elements Hemoglobin Iron-containing protein Binds strongly, but reversibly, to oxygen
** Homeostatic imbalance of RBC s Anemia is a decrease in the oxygen-carrying ability of the blood Sickle cell anemia (SCA) results from abnormally shaped hemoglobin
Formed Elements Figure 10.3
Leukocytes (white blood cells or WBCs) Crucial in the body s defense against disease These are complete cells, with a nucleus and organelles 4,000 to 12,000 WBC per cubic millimeter of blood
**Homeostatic Imbalances of WBC s Abnormal numbers of leukocytes WBC count above 12,000 leukocytes/mm 3 Generally indicates Slightly elevated WBC (11-12,000) =? Abnormally low leukocyte level Commonly caused by certain drugs such as corticosteroids and anticancer agents Leukemia Bone marrow becomes cancerous, turns out excess WBC that are immature
Types of leukocytes Neutrophils act as phagocytes at infection sites, partial to bacteria & fungi eosinophils increases during allergies & parasitic worm infections Basophils histamine containing granules, an inflammatory chemical that makes blood vessels leaky & attracts other WBC s to the inflammatory site
Types of Leukocytes lymphocytes play an important role in immune response (T and B cells) macrophages (monocytes) macrophages that fight chronic infections, i.e., tuberculosis
Formed Elements List of the WBCs from most to least abundant Neutrophils Lymphocytes Monocytes Eosinophils Basophils Easy way to remember this list Never Let Monkeys Eat Bananas
Platelets Smallest of the blood cells Needed for the clotting process when blood vessels rupture Normal platelet count = 300,000/mm 3
Review Questions 2 1. What are the 3 formed elements in blood? 2. Name the function & a few anatomical characteristics of erythrocytes. 3. Name a few characteristics of hemoglobin. 4. What is anemia? 5. Name the function & a few anatomical characteristics of leukocytes. 6. Contrast leukocytosis, leukopenia & leukemia. 7. Name each leukocyte & give one characteristic of each. 8. Name the function & an anatomical characteristic of platelets.
Human Blood Groups Blood contains genetically determined proteins Antigens (a substance the body recognizes as foreign) may be attacked by the immune system Antibodies (proteins in our blood) are the recognizers Blood is typed by using antibodies that will cause blood with certain proteins to clump (agglutination)
Human Blood Groups There are over 30 common red blood cell antigens The most vigorous transfusion reactions are caused by ABO and Rh blood group antigens
ABO Blood Groups Based on the presence or absence of two antigens Type A (30%) Type B 15% The lack of these antigens is called Type O (50%)
ABO Blood Groups The presence of both antigens A and B is called type AB The presence of antigen A is called type A The presence of antigen B is called type B The lack of both antigens A and B is called type O
ABO Blood Groups Blood type AB can receive A, B, AB, and O blood Universal recipient Blood type B can receive B and O blood Blood type A can receive A and O blood Blood type O can receive O blood Universal donor
ABO Blood Groups Table 10.3
Rh Blood Groups Named because of the presence or absence of one of eight Rh antigens (agglutinogen D) that was originally defined in Rhesus monkeys Most Americans are Rh + (Rh positive) Problems can occur in mixing Rh + blood into a body with Rh (Rh negative) blood s
Blood Typing Blood samples are mixed with anti-a and anti-b serum Coagulation or no coagulation leads to determining blood type Typing for ABO and Rh factors is done in the same manner
Blood Typing Figure 10.8
Review Questions 4 1. What is an antigen? an antibody? 2. Blood type is based on the presence or absence of which two antigens? 3. What are the two major human blood groups? 4. Which ABO blood group is the universal recipient? the universal donor? 5. What was the Rh blood group originally defined in?