Glossary X

X chromosome refers to a sex chromosome found in both females and males. Normal females usually have two (2) X chromosomes . Normal males usually have one X along with a Y chromosome. The complete chromosome complement consisting of 46 chromosomes is conventionally written as 46,XX for females and 46,XY for males.
X-linked recessive trait refers to an attribute determined by recessive gene that appears only on X chromosomes ; because the gene determining these characteristics is recessive (that is, dominated by other genes that might appear at the same location on X chromosomes), such characteristics are more common among males; who have only one X chromosome . X-linked recessive trait is also called Sex-linked trait
X-rays refers to a type of light ray that is useful for clinical work of various parts of the body, because they show the presence and position of bones, fractures, and foreign bodies. A clinical disadvantage of X-rays, and specifically X-ray films of the brain, is that there is little differentiation between the brain structures and the cerebrospinal fluid, making the clinical use of this procedure ineffective.
Xanax is the brand name of Alprazolam

Xenophanes (ca. 560 - 478 B.C.) believed people created gods in their own image. Xenophanes noted that dark skinned people created dark-skinned gods and light-skinned people created light-skinned gods. He speculated that the gods created by non-human animals would have the characteristics of those animals. Moreover, he postulated the existence of one all-powerful god without human characteristics but warned that all beliefs are suspect, even his own.
Xenotransplantation refers to transplantation across species, that is, from animals to humans, as in the transplantation of heart values obtained from pigs
XYY syndrome refers to a genetic abnormality in which a male has an extra Y sex chromosome ; characterized by decreased fertility, some genital abnormality, and slight mental retardation.