What is fertilization?
the fusion of a sperm from the male and an immature ovum from the female to form a zygote (fertilized egg).
The reproductive system includes
-reproductive organs (gonads)
-reproductive tract (ducts)
-accessory glands (secrete fluid)
The ovaries (gonads) produce an egg that travels through
-the uterine tubes to reach the uterus.
-the vagina connects the uterus with the exterior
The spermatozoa travels along
the epididymis, the ductus deferens, the ejaculatory duct and the urethra before leaving the body.
Male accessory glands are
-seminal glands (vesicles)
*these secrete into the ejaculatory ducts of the urethra.
The descent of the testes is
-through the inguinal canals that occur during development.
-before this time the testes are held in place by the gubernaculums testis.
during the seventh month of developmental growth, differential growth and contraction of the ______ _______ causes the testes to descend.
-a cord of connective tissue and muscle fibers
the testes remain connected to the abdominal cavity through the
The spermatic cords
*consist of layers of fasia, tough connective tissue, and muscle.
The tunica vaginalis
is a serous membrane that covers the tunica albuginea, the fibrous capsule that surrounds each testis.
spermatogonia (stem cells) form during embryonic development.. they are involved in:
spermatogenesis (production of sperm)
the tip of the head & the tail of each spermatozoon
the tip of the head: acrosomal cap
the tail: single flagellum
*since the sperm lacks most intracellular structures, it must absorb nutrients from environment.
-monitors and adjusts the composition of the tubular fluid
-serves as a recycling center for damaged spermatozoa
-facilitates functional maturation (capacitating)
The ductus deferens (vas deferens)
begins at the epididymis and passes through the inguinal canal as one component of the spermatic cord
The ampulla is
near the prostate
*the junction of the base of the seminal vesicle and the ampulla creates the ejaculatory duct (empties into the urethra)
The accessory glands function
to activate and provide nutrients to the spermatozoa and to produce buffers to neutralize the acidity of the urethra and vagina
Each seminal vesicle
-is an active secretory gland that contributes about 60% of the volume of the semen
-secretions are high in fructose (produce ATP)
The prostate gland
secretes a weakly acidic fluid (prostatic fluid) that contains about 20-30% of the volume of semen
A typical ejaculation release is
2-5 ml which contains sperm count of 20 to 100 million sperm per mililiter
-surround the body of the penis
-consists of 3 masses
*when the smooth muscles in the arterial walls relax, the erectile tissue becomes engorged with blood, producing an erection.
The female reproductive system includes
The ovaries are held in the position by
-the ovarian ligament
-suspensory ligament (connects ovary to the pelvic wall)
Oogenisis has the following steps
1. formation of primary ovarian follicles
2. formation of secondary ovarian follicles
3. formation of tertiary ovarian follicle
5. formation of the corpus luteum
6. formation of the corpus albicans (degeneration of the corpus luteum)
the decline in progesterone and estrogen triggers the secretion of GnRH, which in turn triggers a rise in:
-FSH & LH production, and then the entire cycle begins again.
Each uterine tube has
-an infundibulum (expanded funnel)
-uterine part (intramural part that opens into uterine cavity)
For fertilization to occur, the ovum must encounter spermatozoa during the first
12-24 hours of its passage from the infundibulum to the uterus
normally the uterus bends anteriorly near its base (anteflexion). It is stabilized by broad ligaments:
The uterus is divided into the
-body (largest portion)
The uterine wall can be divided into
a typical 28 day uterine cycle (menstrual cycle) begins with:
-the onset of menses and the destruction of the functional zone of the endometrium
*this process of menstruation continues from 1-7 days
after menses, The proliferative phase begins & the functional zone:
undergoes repair and thickens
*menstrual activity begins at menarche (first uterine cycle) and continues until menopause.
The vagina is
-an elastic, muscular tube extending between the uterus and external genitalia.
-it serves as a passage way for menstrual fluid, receives the penis during sexual intercouse, and forms the lower portion of the birth canal.
The structures of the vulva (pudendum) include
vestibule, labia minora, clitoris, prepuce (hood), and labia majora.
The mammary glands lie
in the subcutaneous layer beneath the skin of the chest and are the site of milk production or lactation.
Milk production is stimulated by
a combination of hormones:
-growth hormone (GH)
-human placental lactogen (HPL)
The placenta (special embryonic organ) that develops functions as
a temporary endocrine organ, producing several important hormones and facilitate gas and nutrient exchange
-typically occurs around the age 50
-is it the time when ovulation and mestruation cease & also is is due to shortage of primordial follicles)
-occurs before age 40
-production of GnRh, FSH, and LH rise, while circulating concentrations of estrogen and progestrins decline
The male climacteric (comparable to menopause) occurs
-between age 50-60
-involves in the decline in circulating testosterone levels and rise in FSH and LH levels
the human reproductive system produces, stores, nourishes, and transports...
-is haploid reproductive cells that have 1/2 the normal number of chromosomes.
the testes hang within the scrotum and each measure:
-about 2 inches long and 1 inch in diameter
-the compartments within the testes are lobules.
menstrual activity begins at ______ and continues until _________
menstrual activity begins at MENARCHE (first uterine cycle) and continues until MENOPAUSE
three stages of the uterine cycle (menstrual cycle)
2. proliferative phase
3. secretory phase