Amniocentesis involves sampling ____
a. the embryo at the eight cell stage
b. fetal cells in the amniotic fluid
c. sperm or egg cells
d. fetal skin tissue
e. placental cells
ANSWER: b
You might also like to view...
Which of the following is useful in the identification of bacteria?
A. Hemolytic, metabolic, and fermentative properties B. Source of the culture specimen C. Growth patterns on selective and differential media D. All of the choices are correct.
Introduction of previously nonexistent genes into a
population may be accomplished by a. nonrandom mating. b. mutation. c. sexual recombination. d. the founder effect. e. changes in chromosome structure.
In the Sanger, or chain termination, method of DNA sequencing, incorporation of the nucleotides stops because
A) the dideoxynucleotide analogs have no 3?-OH group to continue DNA synthesis. B) the dideoxynucleotide analogs have no 5?-OH group to continue DNA synthesis. C) the dideoxynucleotide analogs have no 2?-OH group to continue DNA synthesis. D) the mixture is heated to 92°C to stop DNA synthesis at specific time intervals. E) the dideoxynucleotide analogs are in greater concentration than the actual nucleotides.
Gene duplications in Bacillus subtilis have resulted in a large gene family that encodes ________ transporters.
What will be an ideal response?