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THE RED BLOOD CELL-A MIRACLE PARTICLE

The value of blood as a life-safer and life-sustainer has been appreciated from the earliest times in the history of mankind. In fact, our ancestors recognized the value of blood perhaps more than we do today. Sacrifices, now and in the past, are performed to spill the blood of an animal and thereby appease the angry gods. The conventional symbol of blood is red, and this generally signifies the danger that might follow the spilling of blood through accident or violence. The red flag of revolutionaries is purported to be symbolic of the blood spilled by heroes during popular uprisings. Scientifically, blood is the agent that carries the vitalizing agent oxygen to all tissues of the body, and carries carbon dioxide from the tissues for excretion in the lungs. Blood is given to hospital patients in order that they may not die from excessive bleeding or from severe anemia. Such is the value and importance of blood to all animal and human life that this list could con

MYSTERIOUS FACTS ABOUT CLONING

                                                    In the hands of a trained craftsman, a lump of soft clay can be formed into practical any shape. Embryonic stem cells are the living equivalent of that piece of moist clay; they have the prospective to give rise to virtually all of the over 200 cell types making up the human body. How do they do this? Consider what happens to a newly fertilized egg cell.             Soon after fertilization an egg cell begins to divide. In humans about five days of cell division results in a minute ball of cells called a BLASTOCYST . It is essentially a hollow sphere that is composed of a shell-like outer cell layer and a small cluster of about 30 cells called the inner cell mass, which is attached to the inside wall of the sphere. The outer cell layer becomes the PLACENTA ; the inner cell mass, the human embryo.          At the blastocyst stage, though, the cells of the inner cell mass have not yet begun to specialize into specific cell

MYSTERIOUS DISCOVERY IN THE EYES

            Scientists have long known that the eyes of mammals contain neurons that respond to light and set the body’s internal, or circadian, clock. It was long assumed that this light-sensing function was performed by known visual cells called rods and cones. But in 1999, report the journal Science, researchers found that “mutant mice lacking all rods and cones [who are thus functionally blind] still have light-responsive clocks.” This led researchers to the conclusion that “some other cells in the eye had to be sensing light”            Now these elusive light sensors have been found. Although intermingled with the image-forming rods and cones, the sensors form “a separate visual circuit, running in parallel with this image-forming visual system,” explains Science. The newly discovered circuit’s functions include governing pupil size and melatonin release, synchronizing the body’s internal clock with the cycle of light and dark and other tasks. It may even play a role in

YOUR MARVELOUS RED BLOOD CELLS

                                          THE most common cell in your bloodstream gives blood its red color and is thus called a red blood cell. Just one drop of your blood contains hundreds of millions of such cells. When viewed through a microscope, they look like doughnuts with a depressed center instead of a hole. Each cell is packed with hundreds of millions of hemoglobin molecules is, in turn, a beautiful spherical structure made of about 10,000 hydrogen, carbon, nitrogen, oxygen, and sulfur iron, which give the blood its oxygen-carrying ability. Hemoglobin facilitates the transport of carbon dioxide from the tissues to the lungs, where it is exhaled.     Another vital part of your red blood cells is their skin, called a membrane. This marvelous covering enables the cell to stretch into thin shapes so as to pass through your tiniest blood vessels and thus sustain every part of your body.     Your red blood cells are manufactured in your bone marrow. Once a new cell en