lecture recording on 12 March 2025 at 11.17.25 AM

## Blood Cells and their Components

### Overview of Blood Cells
- Blood is a type of connective tissue with three major functions:
- **Protection** (hemostasis and combating infection)
- **Regulation** (fluid and electrolyte balance, temperature, and oncotic pressure)
- **Transportation** (O2, nutrients, hormones, metabolic waste)

### Blood Volume
- Average adult blood volume: 4.7 to 5.5 liters (approx. 5-6 quarts)
- Comprises:
- 55% plasma (serum)
- 45% blood cells

### Blood Cell Types
1. **Red Blood Cells (RBCs)**
- Carry oxygen (O2) from lungs to cells.
- Key component: **Hemoglobin** (carries O2 and CO2).

2. **White Blood Cells (WBCs)**
- Function in immune response.
- Types:
- **Neutrophils** (50-70% of WBCs): Most common granulocyte, involved in phagocytosis.
- **Eosinophils**: Combat allergic responses and parasites.
- **Basophils**: Involved in inflammation and allergic responses.
- **Lymphocytes** (B cells and T cells): Key players in adaptive immunity.
- **Monocytes**: Differentiate into macrophages and dendritic cells for phagocytosis.

3. **Platelets (Thrombocytes)**
- Aid in clotting processes to prevent bleeding.
- Normal platelet count is greater than 100,000;