Male Reproductive System Flashcards
Gonads
• testes (temperature _____degrees
Celsius lower than the body temp)
2-3
• spermatogenesis, sex hormones production
Testes
• storage and transport of spermatozoa at proper time
• Sex accessories
Sperm maturation
Propel sperm to ejaculatory ducts
Provide nutrients for sperm and fluid
Provide enzymes and proteins for coagulation and liquefaction
Add alkaline mucus to neutralize
prostatic acid and vaginal acidity
Epididymis
Ductus deferens
Seminal vesicles
Prostate gland
Bulbourethral glands
• contains cells in various stages of spermatogenesis (spermatogonia, spermatocytes, spermatids)
Seminiferous tubules
Sertoli is stimulated by
FSH
• aid in the development and maturation of spermatid to a sperm cell
• support, protection & nutritional regulation of the developing spermatozoa
Sertoli cells (stimulated by FSH)
• phagocytosis of cytoplasm shed by developing spermatogenic cells
• establish the blood-testis barrier that prevents contact with immune system
Sertoli
• Leydig cells (stimulated by LH): primary source of testosterone production, synthesize androgens from cholesterol
• Also produce p450 aromatase
• converts testosterone to estradiol
Intersititium
Leydig cells (stimulated by____)
LH
Intersititium
• Leydig cells (stimulated by LH): primary source of_____ production, synthesize____ from cholesterol
• Also produce_____
• converts testosterone to_____
testosterone; androgens
p450 aromatase; estradiol
OTHER PRODUCTS OF SERTOLI CELLS
•_________
• keeps local testosterone levels high for spermatogenesis
•_________
• support sperm cells and spermatogenesis
•_________
• Exerts negative feedback on FSH (testosterone exerts negative feedback on LH)
Androgen-binding protein
Growth factors
Inhibin B
: essential for growth and division of the testicular germinal cells, which is the first stage in forming sperm
Testosterone
stimulates the Leydig cells to secrete testosterone
• Luteinizing hormone
stimulates the Sertoli cells;
without this stimulation, conversion of the spermatids to sperm (the process of spermiogenesis) will not occur/maintain spermatogenesis
• Follicle- stimulating hormone
•________, formed from testosterone by the Sertoli cells when they are stimulated by follicle- stimulating hormone: also essential for spermiogenesis
Estrogens
•_______: necessary for controlling background metabolic functions of the testes.
specifically promotes early division of the spermatogonia
Growth hormone
Testosterone
• Formed by_______
Leydig cells
TESTOSTERONE
• Converted to dihydrotestosterone (more potent form) in the peripheral tissues by_______
• Degraded by the liver and excreted as ______ or ______into bile and urine
5-alpha-reductase
androstenedione or
DHEA
Sex hormone-binding globulin
•Synthesized in the______
• Greater binding for testosterone than estrogen
liver
• High SHBG =
• Low SHBG =
low free testosterone
high free testosterone
Functions of Testosterone
• Development of male body characteristics
• Descent of testes during 2-3 months of gestation
• Distribution of body hair
• Pubis, linea alba, face, chest, back
• Increasing musculature after puberty
: presence or absence of a Y chromosome
: presence of ovaries or testes
: appearance of external genitalia
•Genetic sex
•Gonadal sex
•Genital sex
HYPERGONADOTROPIC HYPOGONADISM
• Klinefelter’s syndrome
• Sertoli Cell-Only Syndrome
Testicular Injury and Infection
Cryptorchidism:
Viral orchitis:
Epididymitis:
Radiation and chemotherapy for cancer:
Trauma
• Klinefelter’s syndrome
• Sertoli Cell-Only Syndrome
Testicular Injury and Infection
Cryptorchidism:
Viral orchitis:
Epididymitis:
Radiation and chemotherapy for cancer:
Trauma
Hypergonadotropic
Hypogonadism
• Presence of extra X chromosome: prevents the testes from functioning normally (atrophic)
Klinefelter’s syndrome
Chrimosome(?)))
• Azoospermia
• Elevated FSH and LH
• Decreased Testosterone
Klinefelter’s syndrome
• 47, XXY
• only Sertoli cells line the tubules (no sperm cells)
HYPERGONADOTROPIC HYPOGONADISM
• Sertoli Cell-Only Syndrome
• characterized by male sterility without sexual abnormality
• Small testes, high FSH levels, azoospermia, and normal testosterone levels
• CONFIRMATORY TEST :_____
HYPERGONADOTROPIC HYPOGONADISM
• Sertoli Cell-Only Syndrome
Testicular biopsy
HYPERGONADOTROPIC HYPOGONADISM
Testicular Injury and Infection
•________: incomplete descent of testis from abdominal cavity to the scrotum
•_________: mumps, echovirus, group B arbovirus
•________: N. gonorrhoede, C. trachomatis, E. coli, M. tuberculosis
•_________: oligospermia or azoospermia occurs after 800 mGy (80 rad)
•________: physical and thermal trauma may lead to the secondary atrophy of testes
Cryptorchidism
Viral orchitis
Epididymitis
Radiation and chemotherapy for cancer
Trauma
HYPERGONADOTROPIC HYPOGONADISM
• ‘genetically male but physically female’, classified as a______
• a genetic disorder that makes XY fetuses insensitive (unresponsive) to androgens
• Deficiency of androgen receptors
• Internally, there is a short blind-pouch vagina and no uterus, fallopian tubes or ovaries (infertile)
• There are testes in the abdomen or the inguinal canal (undescended testes)
• Usually detected at puberty when a girl should but does not begin to menstruate
Testicular Feminization Syndrome/Androgen Insensitivity Syndrome
male pseudohermaphrodite
• Kallmann’s syndrome
HYPOGONADOTROPIC HYPOGONADISM
• characterized by delayed or absent puberty and an impaired
sense of smell
• no secondary sex characteristics: micropenis, cryptorchidism
HYPOGONADOTROPIC HYPOGONADISM
• Kallmann’s syndrome
• NOTABLE SYMPTOM: hyposmia or anosmia
• Hyperprolactinemia: high PRL inhibits GnRH
• Severe stress, malnutrition, opioid/marijuana use
HYPOGONADOTROPIC HYPOGONADISM
• Kallmann’s syndrome
