Two mammals, a sheep and a goat, produce offspring. Only the F1 and F2 generations produce fertile offspring. This
occurs as a result of:
a. mutation.
b. hybrid sterility.
c. microevolution.
d. hybrid inviability.
e. hybrid breakdown
e
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Excessive iron absorption and accumulation to toxic levels is associated with _____
A) excessive blood volume B) a liver abnormality that results in a decreased number of red blood cells C) various forms of inherited or acquired anemia D) the genetic disorder known as hemochromatosis E) menstruation and menopause
A "peer-reviewed" research paper indicates that:
A. graphs and tables are included to prove data. B. several authors are contributing similar papers in the same journal. C. several authors have created the content. D. experts in the field confirm the content reflects high quality work.
Trisomy 21, or Down syndrome, occurs when there is a normal diploid chromosomal complement but one (extra) chromosome 21. Although fertility is reduced in both sexes, females have higher fertility than males. Van Dyke et al
(1995; Down Syndrome Research and Practice 3[2]:65—69 ) summarize data involving children born of Down syndrome individuals. Given the fact that conceptuses with 48 chromosomes (four chromosome 21's) are not likely to survive early development, what percentage of surviving offspring would be expected to have Down syndrome if both parents have Down syndrome? A) One-half of the surviving offspring would be expected to have Down syndrome. B) All the children would be expected to have Down syndrome. C) One-third of the surviving offspring would be expected to have Down syndrome. D) None of the surviving offspring would be expected to have Down syndrome. E) Two-thirds of the surviving offspring would be expected to have Down syndrome.
Which outcome would be the most likely if androgen receptors on cells in the hypothalamus and anterior pituitary suddenly could not bind androgen?
A) Sperm production would increase. B) Sperm production would decrease. C) FSH production would decrease. D) HCG production would increase.