Composition of Blood

What is blood composed of? (2)

Blood is composed of a liquid portion called PLASMA and a solid portion called the FORMED ELEMENTS

What is plasma ?i

The clear, straw-coloured liquid portion of blood

What % of total blood volume does plasma make up ?i

55%

What is plasma made up of ?i

• 90% water

• 10% dissolved substances

Give 5 examples of the dissolved substances in plasma .I

1. Salts

2. Glucose

3. Amino acids

4. Fatty acids

5. Vitamins

6. Enzymes

7. Hormones

8. Cellular waste

9. Albumin

10. Fibrinogen

11. Globulins

What does albumin do ?I

Albumin regulates the amount of water in the blood so it controls blood volume and blood pressure .I

What do globulins do ?I

Globulins help to fight infection (antibodies) .I

What does fibrinogen do ?I

Fibrinogen is involved in blood clotting .I

What % of total blood volume do formed elements take up ?I

45% .I

What are erythrocytes ?I

Red blood cells .I

What is the functiok of RBC ?I

Transport oxygen and carbon dioxide .I

What are 3 physical characteristics of RBCs ?I

1. Biconcave

2. disk shaped

3. No nuclei

What is the lifespan of RBCs ?I

120 days .I

What are leukocytes ?I

White blood cells .I

WBCs increase in numbers during ___ .I

Infection .I

What is the function of WBC ?I

Defend the body .I

What are 4 physical characteristics of WBC ?I

1. Colourless

2. Larger than RBC

3. Contain one or more nuclei

4. Irregular shape that can easily change

Where are RBC and WBC produced ?I

In the bone marrow .I

What are the 5 different types of WBC ?I

1. Neutrophils

2. Monocytes

3. Basophils

4. Eosinophils

5. Lymphocytes

What do neutrophils do ?I

Use phagocytosis to engulf small organisms .i

What do monocytes do ?i

Become large WBC called macrophages .i

What do basophils do (2) ?.

• Release histamine - a substance causing inflammation

• Releases hepatin which is an anticoagulant

What do eusinophils do ?i

Release enzymes to break down blood clots .i

What do lymphocytes do ?i

Involved in the immune response .i

What are thrombocytes ?i

Platelets .i

What is the function of a platelet ?i

Cell fragments/protein involved in blood clotting .i

What are 2 physical characteristics of platelets ?i

1. Small fragments of cytoplasm surrounded by membrane

2. Contain no nuclei

Where are platelets formed ?i

In the bone marrow .i

What is the lifespan of a platelet ?i

About 7 days .i

State the blood clotting process (5 points) .i

1. Injury to a blood vessel

2. Broken vessel releases chemicals to attract platelets

3. Platelets release a chemical that combines with the blood to form an enzyme called thromboplastin

4. Thromboplastin reacts with prothrombin to make the enzyyme thrombin

5. Thrombin reacts with fibrinogen to produce fibrin. Fibrin is insoluble and forms a net around the injured area. This traps blood cells and forms a clot.

What vitamin is used for the blood clotting process ?i

Vitamin K to make prothrombin .i