1. Erythrocytes (or Red Blood Cells)
Number: A normal adult man and woman have about 5 and 4.5 million RBCs per cubic mm of blood respectively An abnormal rise in RBC count is called polycythemia. Decrease in the numbe in the blood and tissues.
The adult haemoglobin moiecule is made of 2 alpha chains with 141 amino acids
each and 2 beta chains with 146 amino acids each People living in hills have more
RBCs of RBCs is called erythrocytopenia which causes oxygen shortage. Shape and Size: The shape of RBCs vary in different classes of vertebrates
in all adult mammals erythrocytes are biconcave, circular and enucleated
(non-nucleated). In camel and llama, RBCs are oval Biconcave shape of RBCs provides more surface area for gaseous exchange than the spherical shape.
Women undergoing menstru ation have less amount of lobin.
Colour: The RBCs impart red colour to the blood due to the pigmenthaemoglobin
Matured mammalian RBCs do not have cell organelles including nucleus, mitochondria, ribosomes centrioles and endoplasmic reticulum. Thus, almost entire cytoplasm is filled with haemoglobin.
Life span: The life span of RBCs is about 120 days Erythropoiesis: Formation of RBCs is called erythropoiesis Hematopoiesis100%
Yolk sac 80%
Vertebral and peivs Live 60%
: Tibia
Sternum 40%
e Ribs
. Spleen 20%
no 10 20 30 40 0 60 70
age in years birth
In early few weeks of embryonic life, primitive nucleated RBCs are produced in yolk sac. In later embryonic stages, RBCs are produced in liver and spleen. From birth onwards, RBCs are produced by bone marrow Iron, proteins, vita min 8/z and folic acid are esental for the formaton of haemoglobin and Racs Haemogiobin of RBCs readily combines
RBCs also participate in Functions of RBCs haemoglobin is an excellent buffer which is largely re for maintaining the pH F Bloo with oxygen to form oxyhaemoglobin trarsporting carbon diaxidebase and help in 02 transport. from tissues to lungs
