The mechanism that keeps the testes cooler than the body's core temperature is called descent of the testes. T or F
The scrotum contains the testes and spermatic cords. T or F
Testosterone stimulates development of the secondary sex characteristics, spermatogenesis, and libido. T or F
Spermiogenesis is the last stage of meiosis. T or F
The gene that codes for the testis-
determining factor (TDF) is found in or on
the Y chromosome.
From their formation to ejaculation, sperm cells take the following pathway:
seminiferous tubule, rete testis, epididymis, ductus deferens, ejaculatory duct, urethra.
The blood-testis barrier (14)
prevents antibodies in the blood from getting to the germ cells.
When do the testes start secreting testosterone?
in the first trimester of fetal development
Testosterone inhibits (16)
gonadotropin-releasing hormone (GnRH) secretion.
Changes called male climacteric are a consequence of
increased secretion of FSH and LH.
Sperm cells get energy to power their movement from _________ contributed by the ____________.
fructose; seminal vesicles
The acrosome contains enzymes used to
penetrate the egg.
_________ have 46 chromosomes, whereas _____________ have 23.
Primary spermatocytes; spermatids
Sildenafil (Viagra) prolongs erection by
inhibiting degradation of cGMP
In the female fetus, the absence of testosterone results in the development of the external genital into clitoris, labia minora, and labia majora. T or F
The uterus is a thick muscular chamber inferior to the urinary bladder. T or F
The vagina has no glands but it is moistened by mucus from glands in the cervical canal. T or F
Although two breast cancer genes are known, most cases are nonhereditary.
T or F
Inhibin modulates the secretion of LH. T or F
Human chorionic gonadotropin (HCG)
stimulates the corpus luteum to grow and secrete estrogen and progesterone. T or F
Progesterone stimulates uterine
contractions. T or F
Prolactin is secreted during pregnancy to stimulate milk synthesis so that milk will be available by the time the infant is born.
T or F
Oxytocin stimulates contraction of myoepithelial cell of the mammary acini.
T or F
The internal female genitalia include the
Most of the natural lubrication during female sexual excitement is provided by the
greater vestibular (Bartholin) glands.
Follicles are located in the
cortex of the ovary.
The earliest sign of puberty in girls is
the onset of breast development.
The term menstrual cycle specifically refers to
the cyclic changes in the uterus determined by shifting hormonal changes.
The ovulated egg is
a secondary oocyte.
The ovum finalizes meiosis
Milk ejection, stimulation of nerve endings in the ____________ leads to the release of ______________ from the pituitary.
nipple and areola; oxytocin
Why is breast milk superior to cow's milk for an infant?
Cow's milk has too much protein and minerals in it.
Neonatal immunity depends on IgG and
IgA acquired through the placenta and colostrum, respectively. T or F
Which of these organ systems faces the greatest physiological challenge in the transitional period after birth?
Older people may require lower drug doses than younger people because
they have lower rates of renal clearance.
Clinical death is widely defined as
Senescence of the immune system makes older people more subject to cancer and infectious disease because of a decline in
antigen-presenting cells and helper T cells.