Blood , its constituents, plasma , 5marks ,, easy to memorize.

 **BLOOD BASICS**

The heart, blood, and blood vessels make up the cardiovascular system.

**What's Blood?**

Blood is like a fluid highway connecting different parts of your body.

**Discovery**

Sir William Harvey found out how blood circulates.

**Blood's Key Points**

1. **Volume**: Around 5-6 liters.

2. **Color**: It's red because of oxyhaemoglobin.

3. **pH**: Slightly alkaline, around 7.4.

4. **Thickness**: Thicker than water, with a specific gravity of about 1.060.

**Composition**

Blood has two main parts: Plasma (55%) and Formed Elements (45%).

**Plasma**

- Liquid part with cells suspended in it.

- Contains water (90-92%) and solids (8-10%).

- Solids include proteins, nutrients, hormones, and waste products.

**Formed Elements**

Three types:

1. Red Blood Cells (RBCs)

2. White Blood Cells (WBCs)

3. Platelets

**Functions**

1. **Transportation**: Moves gases, nutrients, and waste around your body.

2. **Defense**: Fights off invaders like bacteria.

3. **Regulation**: Helps maintain pH, temperature, and water balance.

   - Blood also distributes thermal energy and helps control body temperature.

**Plasma Proteins**

- Important for blood clotting and maintaining osmotic pressure.

- They transport hormones, minerals, and vitamins.

- Act as a nutrient reserve during times of crisis.

**In Short**

Blood's a vital liquid that moves stuff around, fights invaders, and keeps your body in balance. Plasma proteins help with clotting, carrying stuff, and defending against threats. Plus, blood helps regulate temperature and acts as a nutrient backup when needed.

Easy to memorize