Puberty Review Quiz
1. A useful measure of puberty
in a bull is the age at which there are sufficient sperm present in the ejaculate
to successfully breed females.
2. Puberty occurs at 6-7 months
of age in
3. Major factors affecting the
timing of puberty involve hormonal, genetics, nutrional and environmental
4. In the stallion, there is an
initial increase in GnRH pulse amplitude and frequency which drives maturation
of Leydig and Sertoli cells but does not result in an increase in testosterone.
5. Several months before sperm
production in the stallion, FSH increases without an increase in LH. The
FSH effects Sertoli cell multiplication and maturation.
6. Just before sperm production
in the stallion, testosterone will begin to rise.
7. In the female, a decrease in
estradiol negative feedback leads to increasing GnRH pulse frequency and
amplitudes until a GnRH surge occurs. The resulting LH surge causes ovulation.
8. In the female, it is estradiol
exposure that causes the formation of the GnRH surge center in the hypothalamus.
9. In the male, alpha fetal protein
binds testosterone and prevents testosterone from entering into the brain.
The GnRH surge center will then not develop as it requires testosterone conversion
10. The first ovulation in the
female is associated without an estrus due to lack of previous progesterone
in the female. In subsequent cycles, the progesterone during diestrus sensitizes
the hypothalamus so that it will respond to lower estrogen levels and cause
estrus behavior when estradiol increases from the preovulatory follicle.
11. A reduction in nutrition will
not change the time of puberty in cattle.
12. The difference in age of puberty
of brahma and jersey cattle is an example of genetic effects on puberty.
13. In the gilt, which of the
following would result in the earliest age of puberty.
14. In an experiment, ewe lambs
were ovarectomized before puberty and then given estradiol implants. LH was
monitored and found to increase at the expected age of puberty. This experiment
15. If ewe lambs were overectomized
(ovaries removed) at 18 weeks of age and then given an estradiol implant,
at about 27-34 weeks of age which of the following would be true?