The Reproductive System
Which structure guides the descent of the testis into the
For answers, see Appendix H.
Describe the signiﬁcant events of puberty and menopause.
FSH and LH levels, elevated at birth, fall to low levels within a
few months and remain low throughout the prepubertal years.
Between the ages of 10 and 15 years, a host of interacting hor-
mones bring on the changes of puberty.
Failure of the testes to make their normal descent leads to
cause cryptorchidism causes sterility and increases the risk of
testicular cancer, surgery is usually performed during early
childhood to rectify this problem.
Check Your Understanding
If a fertilized egg contains X and Y sex chromosomes, a baby
girl will develop, right?
What is the sexually indifferent stage of development?
(c) Female development
(b) Male development
(a) Sexually indifferent
Approximately 5 weeks
Development of homologous structures of the external genitalia in
The two pictures at the bottom of the ﬁgure show the fully developed perineal