A 40-year-old pregnant woman is concerned about possible genetic defects in her unborn fetus. Her physician recommends prenatal testing and advises her of two methods
Compare and contrast amniocentesis with chorionic villus sampling relative to the time each can be performed, and the relative advantages and disadvantages of each.
What will be an ideal response
Amniocentesis is not normally done before the 14th week of pregnancy. The disadvantage is the risk of injury to the fetus, but ultrasound visualization has dramatically reduced the risk. Tests can be done on the fluid withdrawn to determine the presence of chemicals that serve as markers for specific diseases. The cells themselves are cultured and examined for DNA markers of genetic disease. Karyotyping is also done to check for chromosomal abnormalities. Chorionic villus sampling can be done at eight weeks. It is much faster but may be more risky for the fetus. Karyotyping can be done on the rapidly dividing cells very quickly.
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A plane running vertically or longitudinally from right to left parallel to the midaxillary plane, dividing the body into anterior and posterior parts, is ___________________.
Fill in the blank(s) with the appropriate word(s).
Which directional term means farther from the attachment of a limb to the trunk or farther from the origination of a structure?
a) deep b) contralateral c) lateral d) cephalic e) distal
Which letter is associated with the line that is a thin protein structure that serves as an attachment site for thin filament ends?
A. Z B. H C. M D. I E. A
Which of the following does not represent the correct number of spinal nerves?
A. L1-6 B. C1-8 C. T1-12 D. S1-5