Blood Components and Functions PPT

 

Blood Components and Functions PPT

Blood is a specialized red-colored connective tissue that circulates throughout the body in blood vessels. It transports oxygen, nutrients, and hormones to different parts of the body. It also removes waste products and helps maintain normal body functions.

Biology by Nitin

Blood consists of two main parts:

1. Plasma (liquid part)
2. Formed elements (cells)

Composition of Blood

Blood is made up of:

• 55% Plasma
• 45% Formed Elements

1. Plasma

• Plasma is the straw-colored liquid portion of blood. It forms about 55% of total blood volume.
• Composition of Plasma
• Plasma contains:
• Water (90–92%) – Main component
• Proteins (6–8%)
• Albumin
• Globulin
• Fibrinogen
• Electrolytes (Sodium, Potassium, Calcium, Chloride)
• Nutrients (Glucose, Amino acids, Lipids)
• Hormones
• Waste products (Urea, Uric acid, Creatinine)
• Gases (Oxygen, Carbon dioxide)

Functions of Plasma

• Maintains blood volume and blood pressure.
• Transports nutrients to cells.
• Carries waste products to excretory organs.
• Helps in blood clotting (fibrinogen).
• Maintains osmotic pressure (albumin).
• Helps in immunity (globulins/antibodies).
• Distributes heat throughout the body.

2. Formed Elements

Formed elements include:

1. Red Blood Cells (RBCs)
2. White Blood Cells (WBCs)
3. Platelets

A. Red Blood Cells (RBCs)

Other Name:

Erythrocytes

Structure:

• Biconcave disc shape
• No nucleus (in adults)
• Contain hemoglobin
• Life span: 120 days
• Produced in red bone marrow
• Normal Count:
• Male: 4.5–6 million/mm³
• Female: 4–5.5 million/mm³

Functions of RBCs:

1. Transport oxygen from lungs to tissues.
2. Carry carbon dioxide from tissues to lungs.
3. Help maintain acid-base balance.
4. Give red color to blood (due to hemoglobin).

B. White Blood Cells (WBCs)

Other Name:

Leukocytes

Structure:

1. Larger than RBCs
2. Have nucleus
3. Colorless
4. Life span varies from days to years
5. Normal Count:
6. 4,000–11,000/mm³

Types of WBCs:

WBCs are divided into:

1. Granulocytes

Neutrophils

• Eosinophils
• Basophils

2. Agranulocytes

• Lymphocytes
• Monocytes

Functions of WBCs:

• Protect the body against infections.
• Destroy bacteria and viruses (phagocytosis).
• Produce antibodies (lymphocytes).
• Involved in allergic reactions.
• Remove dead cells and foreign particles.

C. Platelets

Other Name:

Thrombocytes

Structure:

• Small, colorless cell fragments
• No nucleus
• Life span: 7–10 days
• Produced in bone marrow
• Normal Count: 150,000–400,000/mm³

Functions of Platelets:

• Help in blood clotting.
• Prevent excessive bleeding.
• Form platelet plug at injury site.
• Release clotting factors.

Functions of Blood (Overall)

Blood performs the following major functions:

1. Transportation Function

• Oxygen transport
• Carbon dioxide removal
• Nutrient transport
• Hormone transport
• Waste removal

2. Regulation Function

• Maintains body temperature
• Maintains pH balance
• Maintains fluid balance

3. Protection Function

• Prevents blood loss (clotting)
• Fights infection (WBCs)
• Provides immunity (antibodies)

Conclusion

Blood is a vital connective tissue that maintains life by transporting essential substances, protecting against infection, and regulating body functions. It consists of plasma, red blood cells, white blood cells, and platelets, each performing specific and important roles. Proper functioning of blood is essential for maintaining overall health and survival.