THE BLOOD PLASMA. Lecture -1 Dr. Zahoor Ali Shaikh. BLOOD. We will discuss i). Compositions and Functions of Blood, Plasma ii). Hematocrit iii). Plasma Protein. BLOOD. What is Blood ?
Dr. Zahoor Ali Shaikh
i). Compositions and Functions of Blood, Plasma
iii). Plasma Protein
1. Plasma – 55%
2. Cells - 45%
-Erythrocytes [RBC - Red Blood Cells]
-Leukocytes [WBC – White Blood Cells]
Plasma - 55%.
In women – 5 liters
In men – 5.5 liters
Answer: About 280 ml.
We will discuss PLASMA:
- water – 90%
- inorganic constituents – 1%
E.g. Electrolytes – Na+, Cl-, K+, HCO3-,Ca2+
They play role in membrane excitability.
- Plasma protein – 6 – 8%
- Other organic substances present e.g. Glucose, amino acids, lipids and vitamins.
1. Albumin 3.5 – 5 g/dl
2. Globulin 2.5 g/dl
3. Fibrinogen 0.3 g/dl
- molecular weight 69000
- half life 20 days
- synthesized in liver
- Plasma osmotic pressure is mainly due to
- Albumin binds to many substances e.g. bilirubin, bile salts, penicillin for transport in the plasma.
2. Globulins – molecular weight 156,000
- 3 subclasses
(i). Alpha [α]
(ii). Beta [β]
(iii) Gamma [γ]
Function of Alpha & Beta Globulins
Gamma Globulin – Immunoglobulin [Ig]
- IgG – work for defense of body - IgM – work for defense of body
- IgA – present in secretion e.g. saliva, breast milk, intestinal secretion
- IgD – recognize antigen
- IgE – play role in allergic reaction
- molecular weight 400,000
- Fibrinogen play key factor in blood clotting.
- Plasma protein – Albumin, Fibrinogen, Alpha, and Beta Globulin are synthesized in liver, but gamma globulin are produced by plasma cell and
- less protein intake
- protein loss in kidney
- liver disease, decrease synthesis of protein
- intestinal disease, less absorption of protein
- in hypoproteinemia, there is decreased plasma osmotic pressure, therefore, there is Edema [collection of fluid in subcutaneous tissue].