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Anchor sing English songs do

Leucocytes and Lymphocytes<br><br>1. Leucocytes. About 65 per cent of all white cells are leucocytes. Their protoplasm contains granules. Those leucocytes that stain neutral dyes - as the majority do - are called neutrophils. About 1.5 per cent of the total stain with acid dyes and are called eosinophils. And a still smaller number, 0.5 per cent, have granules that stain with basic dyes; These are called basophils. The percentage of oesinophils increases greatly when parasites invade the body.<br><br>2. One characteristic of leucocytes is the irregular, or lobed, appearance of the nucleus. The number of lobes is an index to the cell's age. Ordinarily, about 45 per cent of all leucocytes have a nucleus of three lobes. The life span1 of a leucocyte is short, from four to twelve days.<br><br>3. The function of leucocytes is primarily that of protection against infection. After the skin is pierced and the wound becomes infected, leucocytes from all the body are attracted to this place. Just what attracts them is not known - the process is called chemotaxis - probably some by-product of bacterial metabolism. When they arrive at the wound, they leave the blood stream. They wage war on the invaders, engulfing the bacteria within their own protoplasm, a process called phagocytosis (literally "cell-eating"). Before the infection is not too overwhelming, the victory usually goes to the leucocytes.<br><br>Fig. 7. The formed elements of blood.<br><br>4. Lymphocytes. These cells, which comprise about 35 per cent of the white cells, have a nucleus which practically fills the cell. They are produced in nodes lymph scattered throughout the body; The tonsils are examples of lymph nodes. They live only a few hours after they leave the blood stream. They are incapable of movement and thus cannot pursue bacteria and have little cytoplasm so that phagocytosis is practically out of the question. Bacteria trapped in nodes lymph provoke the formation of them. Unfortunately if the infection is overwhelming, the lymph nodes themselves become infected. Thus in guinea pigs it has been possible to trace the route of tubercle bacilli from the intestines to the lungs, as the route is marked by successively infected lymph nodes. ...

Can the anchor sing English songs<br>