The likelihood that a given gene will result in disease.
- Penetrant trait
A genetic trait (characteristic) that is present in the genome and manifests itself in the individual. By contrast, a nonpenetrant trait is one that, although present, does not manifest itself. If, for example, 100 people have a particular genetic trait but only 80 of them express it, the penetrance of that trait is 80%. The […]
- Penicillin history
The discovery of penicillin, one of the major events in the history of medicine. In 1871 the scientist Joseph Lister by chance noticed that the mould which grows on cheese and fruit can make microbes (germs) grow weaker. He made some successful experiments on patients but did not, it seems, fully recognize the implications of […]
- Penicillin-resistant bacteria
Bacteria that are unaffected by penicillin. Such organisms can sometimes be killed using sulfa drugs, combinations of several medication or other tactics. The rise of penicillin-resistant bacteria is laid to overuse of penicillin drugs, including their ineffective but nonetheless frequent use against colds and other viral infections.
Of or pertaining to the penis.
The external male sex organ. The penis contains two chambers, the corpora cavernosa, which run the length of the organ. These chambers are filled with spongy tissue and surrounded by a membrane called the tunica albuginea. The spongy tissue contains smooth muscles, fibrous tissues, spaces, veins, and arteries. The urethra, which is the channel for […]