Prepared by Dr. Amel Eassawi Physiology Tutorial Prepared by Dr. Amel Eassawi

Functional Anatomy of the Reproductive System List the components of reproductive system? 1. Primary reproductive organ (Gonads) 2. Reproductive tract 3. Accessory sex glands 4. External genitelia What are the primary reproductive organs? Paired testes in the male and paired ovaries in the female.

Functional Anatomy of the Reproductive System What is the functions of mature gonads? 1. Producing gametes (gametogenesis) Spermatozoa (sperm) in male. Ova (eggs) in female. 2. Secreting sex hormones Testosterone in males. Estrogen and progesterone in females.

Functional Anatomy of the Reproductive System What are the functions of the different organs of the reproductive system in males? Testes: Production of sperm (spermatogenesis). Secretion of testosterone. Accessory Sex Glands Seminal vesicles, prostate gland, bulbourethral gland Function: Secretions provide bulk of semen (liquid substance that is conducive to sperm viability) Penis: Organ used to deposit semen in female Male Reproductive Tract Epididymis, ductus (vas) deferens: Sperm maturation Ejaculatory duct: Empty into urethra (canal running length of penis that empties into exterior)

Functional Anatomy of the Reproductive System What are the functions of the different organs of the reproductive system in females? Ovaries: Production of ova (oogenesis). Secretion of estrogen & progesterone. Female Reproductive Tract Oviducts (uterine or Fallopian tubes): Pick up ova on ovulation, serve as site for fertilization Uterus: Responsible for maintenance of fetus during development Responsible for expelling fetus at end of pregnancy The lower portion of the uterus is the cervix (projects in the vagina and contain single, small opening the Cervical canal: Serves as pathway for sperm through the uterus to the site of fertilization. Serves as passageway for delivery of baby from uterus. Vagina: Connects uterus to external environment.

Sex Determination How is the genetic sex is determined? Depends on combination of sex chromosomes. Determined at time of conception. Depends on which type of sex chromosome is contained within the fertilizing sperm.

Sexual Differentiation Discuss the three levels of genetic, gonadal and phenotypic differences between males and females?

Sexual Differentiation Discuss the abnormalities that might take place during sexual differentiation? Pseudo hermaphrodite: Gonad of one sex and genitalia of other 1. Male Pseudo Hermaphrodite: 1. Genetic males whose target cells lack receptors for testosterone are feminized ( testicular feminizing syndrome) 2. Defective testicular development 3. 5α reductsae deficiency ( enzyme, coverts testosteron to DHT) Female phenotype & XY male genotype 2. Female Pseudo Hermaphrodite: Congenital virilizing adrenal hyperplasia Administration of androgen to mother Male phenotype and XX female genotype

Sexual Differentiation Discuss the possible defects produced by maternal non-disjunction of the sex chromosomes at the time of meiosis? (Turner’s syndrome) (Klinefelter’s syndrome)

Puberty Define puberty? Puberty is defined as the stage of physical maturation in which an individual becomes physiologically capable of sexual reproduction.

Puberty Discuss the two mechanisms that influence the onset of puberty? An intrinsic brain timing mechanism Changes in hypothalamic sensitivity to gonadal steroid feedback regulation. “Hypothalamic gonadostat “ theory.

Puberty Which hormones will increase at time of puberty? At puberty secretion of GnRH, FSH,& LH increases and become pulsatile. During childhood , the hypothalamus is extremely sensitive to the negative feedback exerted by the small quantities of estrogen & testosterone produced by the child's ovaries or testes. As puberty approaches , the sensitivity of the hypothalamus is decreased and subsequently , it increase the pulsatile GnRH secretion initially at night . The anterior pituitary responds by progressive secretion of FSH and LH associated with increased secretion of growth hormone .

Puberty What are the mechanism underlying the pulsatile GnRH secretion? Melatonin secretion by pineal gland. 2. Leptin secretion by adipose tissue.

Puberty What are the changes at puberty in females? THELARCHE: The development of breast 2. PUBARCHE: The development of axillary and pubic hairs. 3. MENARCHE: The first menstrual period.

Puberty What is the characteristic of Puberty in Females? 1. Folliculogenesis proceeds 2. Ovulation for first time 3. The first menstrual period. 4. Increase of Estrogen and progesterone Enlist the secondary sexual characteristic in females? 1. Broadening of hips. 2. Subcutaneous fat( buttocks, breast, thighs). 3. Growth of external genitalia. 4. Pubic and axillary hair. 5. Increased sebaceous gland secretions (adrenal androgens).

Puberty What is the characteristic of Puberty in males? 1. Spermatogenesis initiates 2. Increased androgen secretion 3. Growth of accessory sex structures Prostate External genitalia Enlist the secondary sexual characteristic in males? 1. Broadening of shoulders 2. Facial and body hair 3. Growth of larynx( deepening of voice) 4. Pubic and axillary hair. 5. Increased sebaceous gland secretions (adrenal androgens).

Puberty 1. Individual factor (genetic factor) 2. Environmental Factors What is the factors Influencing the Time of Puberty? 1. Individual factor (genetic factor) 2. Environmental Factors Socioeconomic status Nutritional status Health status Geography Altitude

Menopause Define menopause? Absence of menstrual cycle for at least 12 consecutive months What is climacteric or perimenopause period? Period of transition from sexual maturity to cessation of reproductive capability. characterized by: Increasingly irregular cycles. Declining estrogen levels. Loss of estrogen primarily affects skeleton and cardiovascular system.

Menopause What is the characteristic of menopause? Cessation of menstrual cycle Loss of ovarian function Infertility Drop in ovarian steroids (estrogen and progesterone) Rise in gonadotropin hormones Decrease in ovarian inhibin production

Andropause What is the characteristic of andropause? Male reproductive aging. Very gradual compared to menopause. Gradual decrease in sperm production and in testosterone production. May occur after 45 to 50 years. Results from degenerative changes in small testicular blood vessels.