Dictionary

zinc deficiency See deficiency, zinc.

zinc excess Too much zinc, which can cause gastrointestinal irritation, interfere with copper absorption to cause copper deficiency and, like too little zinc, cause immune deficiency. See also zinc.

zinc ointment A topical preparation that contains zinc and is applied to protect the skin from irritation or sunburn. Zinc ointment is also often the basis for commercial preparations for preventing diaper rash. It should not be used on skin that is already broken or irritated, however.

zinc oxide A form of zinc that has been used in zinc ointments.

zinc sulfate A form of zinc that can be administered in eyedrops. Zinc sulfate is used in some types of eye tests.

Zinsser disease See Brill-Zinsser disease.

Zollinger-Ellison Syndrome (ZES): 1. Pathophysiology 2. Causes & Associations 3. Symptoms 4. Diagnosis 5. Treatment 6. Prognosis

zona pellucida The strong membrane that forms around an ovum as it develops in the ovary. The membrane remains in place during the egg’s travel through the fallopian tube. To fertilize the egg, a sperm must penetrate the thinning zona pellucida. If fertilization takes place, the zona pellucida disappears, to permit implantation in the uterus.

zoonosis An infection that is known in nature to infect both humans and lower vertebrate animals.

Y chromosome The sex chromosome that is found, together with an X chromosome, in most normal males. The Y chromosome contains the unique male-determining gene and the male fitness genes that are active only in the testis and are responsible for the formation of sperm. Other genes on the Y chromosome have counterparts on the…

Y chromosome sex-determining region The region on the Y chromosome that decides the sex of the individual. Abbreviated SRY. SRY is necessary for male determination. It encodes the testis-determining factor. Mutations in SRY are responsible for XY females with gonadal dysgenesis who appear to be normal females at birth but at puberty do not develop…

Y map The array of genes on the Y chromosome.