- Z chromosome
A sex chromosome in certain animals, such as chickens, turkeys, and moths. In humans, males are XY and females XX, but in animals with a Z chromosome, males are ZZ and females are WZ.
- ZAP-70
Zeta-chain-associated protein kinase 70. A member of the protein tyrosine kinase family, ZAP-70 is normally expressed in T cells and natural killer cells and has a critical role in the initiation of T-cell signaling. ZAP-70 is expressed in T cells and tumors of T-cell lineage. A high level of ZAP-70 expression appears restricted to T-cell […]
- Zebra
‘When you hear hoof beats, think of horses, not zebras.’ For example, when someone develops a mild transient cough, a virus infection is the most logical and likely cause, and tuberculosis is a zebra.
- Zygotic lethal gene
A gene that is lethal (fatal) for the zygote, the cell formed by the union of a sperm (male sex cell) and an ovum (female sex cell). The zygote would normally develop into an embryo, as instructed by the genetic material within the unified cell. However, a zygotic lethal gene scotches prenatal development at its […]
- Zygote intrafallopian transfer (ZIFT)
A technique in which a woman’s egg is fertilized outside the body, then implanted in one of her fallopian tubes. This technique is one of the methods used to overcome infertility, the inability of couples to produce offspring on their own. First, the egg and the male sperm needed to fertilize it are harvested. Then […]
- Linkage
The tendency for genes to be inherited together as a package because of their location near one another on the same chromosome.
- Plummer’s disease
Toxic multinodular goiter. Also called Parry’s disease.
- Captioning
Captioning: The text display of spoken words, presented on a movie screen or a television (or other type of monitor), that allows a deaf or hard-of-hearing viewer to follow the dialogue and the action of a program simultaneously. This is much like providing motion-picture subtitling for a foreign-language film.
- Matter, white
The part of the brain that contains myelinated nerve fibers. The white matter is white because it is the color of myelin, the insulation that covers nerve fibers.
- Chen, Zhong Wei
Chen, Zhong Wei: (1929-2004) Chinese surgeon considered the “father of replantation.” Dr. Chen was the first to reattach a severed hand with success which he did in 1963.