Blood

Question 1

Functions of Blood (3)

Answer 1

• Transportation of oxygen & CO2 + nutrients + wastes
• Regulation of body temp, pH & fluid volume
• Protection by mounting an immune response and production of antibodies

Question 2

Composition of Blood (3)

Answer 2

1. Erythrocytes (44%)
2. Buffy Coat (1%)
3. Plasma (55%)

Question 3

Hematocrit

-variation between females and males

Answer 3

-Hematocrit: the % of the volume of all formed elements (erythrocytes, leukocytes & Platelets) in one’s blood

• Females = 38-46%
• Males = 42-56%

Question 4

Erythrocytes

• features
• rouleaux

Answer 4

• AKA Red blood cells
• lack nuclei & other organelles
• relatively small (7.5um diameter)
• unique biconcave shape
• As pass through small blood vessels, line up in single file termed rouleaux

Question 5

Hemoglobin in Erythrocytes

Answer 5

• Every erythrocyte contains 280 million molecules of red pigmented protein called hemoglobin
  
  • is capable of reversibly transporting O & CO2
• consists of 4 globin protein molecules;
  
  • 2 x alpha chains
  • 2 x beta chains

Question 6

Leukocytes -general features

Answer 6

• Possess nucleus and organelles
• help initiate an immune response & defend body against pathogens
• 1.5-3 x larger than erythrocytes
• capable of leaving blood vessels and entering a tissue (diapedesis)
• are attracted to site of infection - called chemotaxis

Question 7

Types of Leukocytes (5)

Answer 7

• Neutrophils
• Eosinophils
• Basophils
• Monocyte
• Lymphocyte

Question 8

Types & functions of Leukocytes

Answer 8

• Neutrophils: Multi-lobed nuclei; phagocytize pathogens & release enzymes that target pathogens
• Eosinophils: Bilobed nuclei; phagocytize antigen-antibody complexes and allergens
• Basophil: Bilobed many granules. Release histamine (vasodilator) and heparin (anticoagulant) during reactions
• Lymphocyte: round nucleus; attacks pathogens & abnormal/infected cells. Coordinate immune cell activity and produce antigens
• Monocyte: Kidney shaped nucleus, can exit blood vessels and become macrophages. Phagocytize pathogens, cellular debris, dead cells

Question 9

Granulocytes & agranulocytes - leukocyte classification

Answer 9

-Leukocytes divided into 2 classes; based on presence of absence of visible organelles (termed granules)
Granulocytes: Neutrophils, eosinophils, basophils
Agranulocytes: Lymphocyte & Monocyte

Question 10

Platelets

• What they are
• what they are derived from
• Involved in

Answer 10

• irregular membrane enclosed cellular fragments
• represent shed cytoplasm from cells in red bone marrow called megakaryocytes
  
  • are approx. 15 x larger than erythrocytes
• platelets are about 1/4 size of erythrocytes
• Involved in the clotting of blood

Question 11

Erythropoiesis

Answer 11

• Is the process of erythrocyte production
• about 3 million erythrocytes produced per second
• during maturation, all organelles w/in erythrocyte degenerate leaving it with nothing more than a bag of hemoglobin