Puberty

Question 1

What is puberty?

Answer 1

The acquisition of reproductive competence.

Question 2

True or False: Puberty is a single event.

Answer 2

False, it occurs over time.

Question 3

What two factors influence puberty?

Answer 3

1. Genetics.
2. Environment.

Question 4

What hormone is required for puberty to begin?

Answer 4

GnRH (triggers the release of FSH and LH) at appropriate frequencies and quantities.

Question 5

What are the three criteria for puberty onset in females?

Answer 5

1. Age of first estrus (easy to detect).
2. Age of first ovulation (difficult to detect).
3. Age of “safe” pregnancy (Most practical criterion).

Question 6

What are the four criteria for puberty onset in males?

Answer 6

1. Age of first ejaculation.
2. Age when reproductive behavior is first expressed (Easy to determine).
3. Age when sperm first appears in the ejaculate.
4. Age when the threshold number of sperm is reached (most valid and practical criterion).

Question 7

What are the four factors that affect puberty?

Answer 7

1. Genetic.
2. Hormonal.
3. Nutritional.
4. Environmental.

Question 8

What part of the brain does puberty onset depend on and why?

Answer 8

1. The hypothalamus.
2. GnRH release.

Question 9

What is required for ovulation to begin in females?

Answer 9

1. Full neural activity.
2. A preovulatory GnRH surge.
3. Estradiol.
4. A fully functional surge or tonic center.

Question 10

What do GnRH, LH, and FSH look like in the prepubertal period?

Answer 10

1. Minimal GnRH release.
2. Low LH and FSH.
3. Minimal folliculo-or spermatogenesis.

Question 11

What do GnRH, LH, and FSH look like in the pubertal period?

Answer 11

1. Increase in GnRH pulse frequency and amplitude.
2. Increase in LH and FSH pulses.
3. Folliculo-and spermatogenesis occur.

Question 12

What regulates the GnRH pulses in females?

Answer 12

1. The development of a surge center.
2. Change in feedback sensitivity to E2.

Question 13

True or False: Animals of the same genus go through puberty at around the same time.

Answer 13

False. There are even differences between different breeds.

Question 14

What happens to the rate of puberty as the rate of gain increases?

Answer 14

The rate of puberty increases.
*Many animals must reach a certain percentage of there end weight before they start puberty.

Question 15

What happens to the number of weeks it takes to reach puberty when more animals of the same gender are placed together?

Answer 15

The number of weeks required decreases.

Question 16

Which management style results in the lowest number of weeks it takes to reach puberty?

Answer 16

Placing males and females in direct contact with one another.