Blood: The Lifeline of Our Body

1. What is Blood?

Blood is a specialized fluid connective tissue that circulates through the body, delivering oxygen and nutrients. In human body, Average blood present is 5 to 6 liters. It makes up about 7-8% of your body weight and it is red due to iron in hemoglobin. It occurs in Bone Marrow Cells and Liver cells (in embryo). It's pH value 7.4 (Slightly Basic). 

2. Composition of Blood: The Four Key Components

Plasma (55%) – A yellowish liquid that carries nutrients, hormones, and waste.

Red Blood Cells (RBCs) (45%) – It is also called Erythrocyte. It contain hemoglobin that helps in transport of oxygen in the form of Oxyhemoglobin. It imparts red color to the blood.

Number of RBC = 4.5 to 5.5 Million.

Erythrocytopenia occurs due to deficiency of RBC in the blood.

Life Span of RBC = 120 Days. 

White Blood Cells (WBCs) – Fight infections and foreign invaders.

Platelets – Small cell fragments that help in blood clotting.

3. Functions of Blood: More Than Just a Red Liquid

Transport: Carries oxygen from the lungs to the rest of the body. 

Defense: White blood cells fight infections and diseases by providing immunity.

Clotting: Platelets prevent excessive bleeding when injured.

Regulation: Helps maintain body temperature and pH balance.

4. Types of Blood Groups: What’s Your Type?

Blood types: A, B, AB, and O.

The universal donor (O-) and universal recipient (AB+).

The Rh factor: Positive (+) or Negative (-).

Importance of knowing your blood type (for medical emergencies and transfusions).

5. How Blood Circulates: The Role of the Heart & Blood Vessels

The Heart pumps blood through the body and it pumps about 7,500 liters of blood every single day.

Arteries carry oxygen-rich blood away from the heart.

Veins bring oxygen-poor blood back to the heart.

Capillaries are tiny vessels where oxygen and nutrients are exchanged with cells.

6. Blood Disorders & Diseases

Anemia: Low red blood cells cause fatigue and weakness.

Leukemia: A type of blood cancer affecting white blood cells.

Hemophilia: A genetic disorder where blood doesn’t clot properly.

7. The Amazing Process of Blood Clotting

Platelets and clotting factors work together to seal wounds.

How excessive clotting can cause heart attacks or strokes.

8. Conclusion: Blood – A Marvel of Biology

Recap of why blood is essential.

Encourage good habits like staying hydrated and eating iron-rich foods.

Read about : Plant Tissue

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