Normal karyotype w
Sex chromosomes d. Fetal karyotype (normal female)
Three ways to check a fetus's chromosomes. (a) In amniocentesis, a needle is inserted into the uterus to collect a sample of amniotic fluid, which contains fetal cells. The cells are grown in the laboratory, dropped onto a microscope slide to spread the chromosomes, and the chromosomes stained and arranged into a chart (karyotype). (b) Chorionic villus sampling (CVS) removes cells of the chorionic villi, whose chromosomes should match those of the fetus because they all descend from the fertilized ovum. (c) Fetal cell sorting separates fetal cells from the woman's circulation. A genetic counselor interprets results of these tests—a fetal karyotype (d)—for patients.
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This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.