DEFINITION:1 orig., venom, as of a snake 2 a) any of a kingdom (Virus) of prokaryotes, usually ultra microscopic, that consist of nucleic acid, either RNA or DNA, within a case of protein: they infect animals, plants, and bacteria and can reproduce only within living cells so that they are considered as being either living [...]

DEFINITION:1 the branch of biology that deals with heredity and variation in similar or related animals and plants 2 the genetic features or constitution of an individual, group, or kind. April 28, 1994: Biological clock found in mice. Evidence for a so-called biological clock in mice was announced by scientists at Northwestern University in Illinois. [...]

Genetic Research After Mendel Chromosome, microscopic, threadlike part of the cell that carries hereditary information in the form of genes; among simple organisms, such as bacteria and algae, chromosomes consist entirely of DNA and are not enclosed within a membrane; among all other organisms chromosomes are contained in a membrane-bound cell nucleus and consist of [...]

Sex Linkage Linked genes occur on the sex chromosomes as well as on the non sex chromosomes, or autosomes. In humans, a woman carries two X chromosomes and 44 autosomes in each body cell and one X chromosome and 22 autosomes in each egg. A man carries one X and one Y chromosome and 44 [...]

A disease is a condition that impairs the proper function of the body or of one of its parts. Every living thing, both plants and animals, can succumb to disease. People, for example, are often infected by tiny bacteria, but bacteria, in turn, can be infected by even more minute viruses. Hundreds of different diseases [...]

What Happens When Immunity Backfires Paradoxically, a person’s immunity system can backfire and develop auto-antibodies against his own body tissue. In many diseases of unknown cause, doctors have found many unusual antibodies in the blood serum of patients. Rheumatoid arthritis (RA), chronic disease of the connective tissue, causing painful sensations in joints and muscles. Doctors [...]

DEFINITION: the branch of biology dealing with the splicing, and recombining, of specific genetic units from the DNA of living organisms: it is used to modify the existing genetic codes to produce new, or improved, species, valuable biochemicals. 1865: The birth of genetics. It was unfortunate for the biological sciences that Gregor Mendel was an [...]

The Prairie Dog Coterie – A Complex Social Group The prairie dog is a rodent that maintains an elaborate social organization. Bond formation among prairie dogs depends on the exchange of auditory, visual, and chemical stimuli. The coterie the social unit of the prairie dog is maintained in a network of burrows occupying a fairly [...]

It has been said that thoughts of death lead necessarily to the development of religion. It is difficult to imagine what need there would be for religion in a world in which no one ever died or became ill. All religions attempt to give answers to basic questions: From where did the world come? What [...]

 Human beings are born sexual. Humans develop a strong sense of being male or female. This sense of maleness or femaleness and the behaviour exhibited because of it is called human sexuality. The characteristics of being a man or a woman involve biological, psychological, and sociological behaviours as well as the reproductive capacity and sexual [...]