Blood contains plasma, red blood cells, white blood cells, and platelets. Plasma is mostly water containing proteins, ions, nutrients, and waste. Red blood cells carry oxygen to tissues and carbon dioxide back to the lungs using hemoglobin. Platelets form blood clots to prevent blood loss from damaged vessels. White blood cells include neutrophils, lymphocytes, monocytes, eosinophils, and basophils which fight infection and disease. Each blood component has specialized functions in transporting substances and protecting the body.

1. COMPONENTS OF BLOOD AND THEIR
FUNCTIONS
THE OXFORD COLLEGE OF SCIENCE
DEPARTMENT OF BIOTECHNOLOGY
Presented By : Shloka Gulhane
(M.Sc, 1st year )
Seminar Guide : Dr. Kamatchi
Associate Professor

2. Sr.
no.
CONTENT
1. Blood
2. Plasma
3. RBC
4. Platlets
5. WBC
a. Neutrophil
b. Eosinophil
c. Basophil
d. Lmymhocytes
e. Monocytes
6. Reference

3. BLOOD
 Blood is a body fluid in humans and other animals that delivers necessary substances
such as nutrients and oxygen to the cells and transports metabolic waste products away
from those same cells.
 It includes plasma (the liquid portion), blood cells (RBC and WBC), and cell fragments
called platelets.
 Plasma makes up about 55% of total volume of blood and other 45 % is made up by
blood cells and platelets .

4. PLASMA
 Plasma is the main component of blood and consists mostly of water, with proteins,
ions, nutrients, and wastes .
 It can be isolated by centrifuging the blood at high speed. Blood cells and platelets
which are denser settles at the bottom of tube forming red and white layer and plasma
remains on top forming yellow layer.

5.  Plasma contains about 90% of water and other 10% is made up of ions, proteins ,
nutrients( Important to maintain blood pH and osmotic balance.), dissolved gasses
and wastes.
 Some of the molecules found in plasma have more specialized function, example-
 Hormone- Act as long distance signal.
 Antibodies- Recognize and neutralize pathogens.
 Clotting Factor- Promote formation of blood clot at the wound site.

6. RBC (Erythrocytes)
 Red Blood Cells – In humans, red blood cells are small and biconcave, 78
micrometer in size, and do not contain mitochondria or a nucleus when mature.
 Small size and biconcave shape increase the surface area-to-volume ratio,
improving gas exchange, while lack of a nucleus makes additional space
for hemoglobin, (a key protein used in oxygen transport.)
 In the lungs, red blood cells take up oxygen, and as they circulate through the rest
the body, they release the oxygen to the surrounding tissues. Red blood cells also
play an important role in transport of carbon dioxide, a waste product, from the
tissues back to the lungs.

7.  Some of the carbon dioxide binds directly to hemoglobin, and red blood cells also
carry an enzyme carbonic anhydrase, that converts carbon dioxide into
bicarbonate. The bicarbonate dissolves in plasma and is transported to the lungs,
where it's converted back into carbon dioxide and released.
 Red blood cells have an average life span of 120 days. Old or damaged red blood
cells are broken down in the liver and spleen, and new ones are produced in the
bone marrow.
 Red blood cell production is controlled by the hormone erythropoietin, which is
released by the kidneys in response to low oxygen levels.

8. Platelets (Thrombocytes)
 Platelets (Thrombocytes) -are cell fragments involved in blood clotting.
 Produced when large cells called megakaryocytes break into pieces. Platelets are
roughly disc-shaped and small, about 2-4 micrometer in diameter.

9.  When there is damaged , platelets are attracted to the wound site, where they form
a sticky plug. The platelets release signals, and activate a signaling cascade that
converts fibrinogen, a water-soluble protein present in blood plasma, into fibrin (a
non-water soluble protein). The fibrin forms threads that forms a platelet plug,
making a clot that prevents further loss of blood.

10. WBC (Leukocytes)
 White blood cells, (leukocytes), make up less than 1 percent of the cells in blood.
 They are primarily involved in immune responses, recognizing and neutralizing
invaders such as bacteria and viruses.
 They have a normal nucleus and mitochondria.
 The granulocytes, includes neutrophils, eosinophils, and basophils, all of which
have granules in their cytoplasm when stained.
 The agranulocytes, includes monocytes and lymphocytes, which do not have
granules in the cytoplasm.

11. Neutrophil
 Most abundant white blood cell, constituting 60-70% .
 They are 10-12 micrometer in diameter.
 They have a multi-lobed nucleus. Granules are fine pale pink stained present in
cytoplasm.
 Neutrophils are active in phagocytosis. Mainly attack bacteria and fungi.
 The average lifespan neutrophils is between 5 hours to few days.

12. Eosinophil
 Eosinophil's compose about 2-4% of the total WBC.
 They are 10-12 micrometer in diameter.
 They have bilobed nucleus. The cytoplasm is full of granules that stain pink-orange
color with eosin staining.
 The average lifespan eosinophil is between 8-10 days.
 Eosinophil's target large parasites and modulate allergic inflammatory response.

13. Basophil
Basophil's compose about 0.4 % of the total WBC.
They are12-15 micrometer in diameter.
They have bilobe or trilobe shape nucleus. Granules are present
in large number and stained dark violet.
The average lifespan basophil is few hours to few days.
Basophil's release histamine for inflammatory responses.

14. Lymphocytes
 Lymphocytes are much more common in the lymphatic system than in blood.
Compose 30% of total WBC Lymphocytes.
 Have a deeply stained nucleus and have a relatively small amount of cytoplasm.
 Smaller lymhocytes are 7-8 micometer in diameter and lager lymhocytes are 12-15
micrometer in daimeter.

15. Lymphocytes include:
 B cells- releases antibodies and assists activation of T cells
 T cells- CD4 + Th (T helper) cells: activate and regulate T and B cells.
CD8 + cytotoxic T cells : virus -infected and tumor cells.
 Natural killer cells : virus-infected and tumor cells.

16. Monocyte
 Monocyte compose about 5.3 % of the total WBC.
 They are 15-30 micrometer in diameter.
 They have bean shape or kidney shape nucleus.
 The average lifespan basophil is hours to days.
 Monocytes migrate from the bloodstream to other tissues and differentiate into tissue
resident macrophages , Kupffer cells in the liver.

17. Reference :
1. Richard, Thomas, barbara . “Kuby Immunology”,4th Edition. Pg.41-42.
2. Alberts B, Johnson A, Lewis J, et al. (2002). “Molecular biology of the cell” 4th
edition, New York: Garland Science, ncbi-Table 22-1.
3. Component of blood- KHAN ACADEMY.

18. THANK YOU