What type of tissue is blood?
Blood is a continuously regenerated connective tissue.
What are the main functions of blood?
Transportation, protection, and regulation.
What does blood transport?
Oxygen, carbon dioxide, nutrients, hormones, heat, waste products, formed elements, dissolved molecules, and ions.
How does blood protect the body?
Leukocytes and plasma proteins defend against pathogens; platelets and clotting proteins prevent blood loss.
How does blood regulate body conditions?
Maintains body temperature, pH (7.35–7.45), and fluid balance.
What is the average adult blood volume?
About 5 liters (range 4–6 L).
How does oxygenation affect blood color?
Oxygen-rich blood is bright red; oxygen-poor blood is dark red.
What is blood viscosity compared to water?
Blood is 4–5 times thicker than water.
What increases blood viscosity?
Increased erythrocyte number or decreased plasma fluid.
What is hematocrit?
The percentage of erythrocytes in blood.
Normal hematocrit range for males?
42–56%.
Normal hematocrit range for females?
38–46%.
What are the three formed elements of blood?
Erythrocytes, leukocytes, and platelets.
What is plasma composed of?
92% water, 7% plasma proteins, 1% dissolved solutes.
What are the main plasma proteins?
Albumin, globulins, fibrinogen, regulatory proteins.
What is the main function of albumin?
Maintains colloid osmotic pressure and transports substances.
What are gamma globulins?
Immunoglobulins (antibodies).
What is fibrinogen’s function?
Converted to fibrin to form blood clots.
What is serum?
Plasma without clotting proteins.
What is the structure of erythrocytes?
Small, flexible, biconcave discs without nucleus or organelles.
What is hemoglobin made of?
Four globin chains (2 alpha, 2 beta), each with a heme group containing iron.
How many oxygen molecules can one hemoglobin bind?
Four.
Where does oxygen bind on hemoglobin?
To the iron ion in the heme group.
Where does carbon dioxide bind on hemoglobin?
To the globin protein.
