The red blood cells are most numerous formed elements of the blood . They are the most abundant cells in the human body . A unique features of the red blood cells is the presence of a red, oxygen – carrying pigment , the hemoglobin ,in their cytoplasm.
Red blood cells
- What are red blood cells ?
- What is the lifespan and disposal of red blood cells ?
- What are the components of red blood cells ?
RBCs contains hemoglobin and are covered with membrane composed of proteins and lipids . Hemoglobin is an iron- rich proteins that gives its red color from their respiratory pigments . RBCs contain hemoglobin which transports oxygen from the lungs to the rest of the body , such as to the muscles,where it releases the oxygen lead .
- What are the shape of red blood cells ?
RBCs have a shape of a disk that appears to be ‘ caved in ‘ or almost flattened in the middle ; this is called biconcave . This biconcave allows the RBC to carry oxygen and pass through even the smallest capillaries in the lungs . This shape also allows RBCs to stack like dinner plates and bend as they flow smoothly through the narrow blood vessels in the body . RBCs lack a nucleus ( no DNA ) and no organelles , meaning that these cells cannot divide or replicate themselves like the cells in our skin and muscles .
The shape of red blood cells varies in different vertebrate classes . In fishes , amphibians , reptiles and birds , they are oval , biconvex and nucleated . In mammals (e.g., man ), they are circular , biconcave , denucleated discs . Their central part is thinner than the margin . This shape provides flexibility and results in a 20 to 30 % increase in surface area as compared to a sphere. This favours quick diffusion of gases . Camel and llama are exceptional among mammals in having oval RBCs.
- What size of red blood cells ?
Human RBCs are smaller than the white blood cells . They are 7-8 micron metres in diameter and 2 micron meter thick near the rim . Small size of RBC provides it greater surface area for quick diffusion of O2 into it .
- What is the normal number of RBC in human body ?
The normal RBC range of healthy adult man and woman have 5 and 4.5 million RBCs per cubic milimeter of blood respectively . This is called the total RBC count .
- What does a low red blood count mean ?
The RBC count decrease or low in anaemia . Anaemia may be caused by loss of blood (haemorrhage) , destruction of RBCs (haemolysis) , or faulty formation of blood . Symptoms of anaemia is feeling fatigue and weakness .
- What does a high red blood count mean ?
The RBC count increase or high it means that there is a shortage of oxygen in the system and the body creating more red blood cells to carry more oxygen to make up for the shortage . It is a risk marker for some very serious illness : heart disease , kidney disease and stroke . Doctor may recommend a procedure or medication to lower . In a procedure called a phlebotomy , a healthy professional inserts a needle into your vein and drains blood through a tube into a bag or container .
- What does an abnormal red blood count mean ?
An abnormal rise in red blood cells count is called polycythemia .
Structure of red blood cells
Formation of red blood cells
Colour of Red blood cells
- What is colur of red blood cells ?
The colour of red blood cells look yellowish when seen singly and red viewed in bulk . They impart red colour to the blood . The colour is due to the presence of a solution of iron – containing pigment, hemoglobin in them .