1. Human Reproductive Systems

2. Functions of the Reproductive System
Produces and nurtures sex cells
Transports sex cells to site of fertilization
Secretes hormones vital to the development and maintenance of sexual characteristics
Regulates reproductive physiology

3. Male Reproductive System

4. Testes - Location
Primary sex organs in which sperm cells and male sex hormones are formed
Located within scrotum

5. Testes - Structure
Surrounded by white fibrous capsule that divides testis into about 250 lobules
Each lobule contains seminiferous tubules
Interstitial cells secrete sex hormones
Tubules unite to form epididymis  vas deferens

7. Spermatogenesis Process of producing sperm cells
Produced throughout reproductive life
Collect in seminiferous tubules and pass to epididymis to mature

9. Sperm Structure
Flattened head, cylindrical midpiece, and elongated flagellum
Head contains nucleus (23 chromosomes)
Acrosome
Many mitochondria in midpiece

13. Epididymis Tightly coiled, threadlike tube Connects to ducts of testis
Becomes the vas deferens
Sperm cells are initially nonmotile here

15. Vas Deferens Aka ductus deferens
Muscular tube that passes from the testis into the abdominal cavity
Ends behind the urinary bladder
Unites with duct of seminal vesicle to form ejaculatory duct
Ejaculatory duct passes through prostate
Empties into urethra

17. Seminal Vesicles Convoluted sac-like structures
Attach to the vas deferens near base of urinary bladder
Secrete slightly alkaline fluid:
Helps regulate pH
Contains fructose to supply sperm with energy
Contains prostaglandins that trigger contractions within female

19. Bulbourethral Glands Aka Cowper’s glands
Pair located posterior to the prostate
Produces mucus-like fluid in response to sexual stimulation
Fluid lubricates end of penis

20. Semen
Fluid conveyed by the male urethra to the outside of the body during ejaculation
Consists of sperm and secretions of the seminal vesicles, prostate, and bulbourethral glands
pH = 7.5
Volume varies – 2-6 ml
Average sperm count = 120 million / ml
Sperm are nonmotile until they mix with glandular secretions

21. Scrotum
Pouch of skin that hangs from lower abdominal region behind the penis
Medial septum
Holds the testes

22. Penis Conveys urine and semen through the urethra to the outside
Erection
Shaft contains 3 columns of erectile tissue:
Corpora cavernosa
Corpus spogiosum

23. Penis Structure Enlarges at distal end to form glans penis Prepuce
Emission
Ejaculation
Circumcision

24. Male Sex Hormones
Most changes during puberty are controlled by the hypothalamus (begins around age 10)
Luteinizing hormone (LH) – promotes development of testicular cells that secrete male sex hormones
Follicle-stimulating hormone (FSH) – stimulates cells of seminiferous tubules to respond to testosterone  spermatogenesis
Androgens – testosterone; stimulates enlargement of testes and development of secondary sexual characteristics

25. Male Secondary Sexual Characteristics
Growth of body hair on face, chest, axillary, and pubic regions
Larynx enlarges and vocal cords thicken  lower pitch to voice
Skin thickens
Muscular growth increases, shoulders broaden, waist narrows
Bones thicken and strengthen
Increased rate of cellular metabolism and RBC production

27. Female Reproductive System

28. Functions of Female Reproductive System
Production and maintenance of ova
Transportation of ova to site of fertilization
Provision of favorable environment for developing offspring
Movement of developed offspring to the outside
Production of female sex hormones

29. Ovaries - Structure Solid, ovoid structures
Lie in shallow depressions in lateral wall of pelvic cavity
Inner medulla
Outer cortex

31. Oogenesis Primordial follicles formed during prenatal development
Each follicle consists of single primary oocyte
Meiosis begins in primary oocyte and halts until puberty
At puberty, meiosis continues in some primary oocytes
Polar bodies

33. Follicle Maturation
During maturation of primordial follicle, surrounding follicular cells proliferate, organize into layers, and form fluid-filled cavity around the oocyte.
Follicle cavity presses oocyte to one side, forming “blister” on the surface of the ovary.
20 primary oocytes may begin maturing, but usually one outgrows the others.

36. Ovulation
Release of the secondary oocyte and first polar body from the follicle
Hormones cause mature follicle to swell rapidly and its walls weaken
After ovulation, secondary oocyte and 1-2 layers of follicular cells surrounding it are propelled into the uterine tube.
If not fertilized, the oocyte degenerates.

38. Uterine Tubes Aka fallopian tubes or oviducts
Open near the ovary and pass medially to the uterus
Infundibulum
Fimbriae

41. Uterus - Functions Hollow, muscular organ shaped like an inverted pear
Receives the embryo from the uterine tube and sustains its development
Muscles contract during intercourse to help transport sperm
Size changes greatly during pregnancy

42. Uterus - Structure
Located in anterior portion of pelvic cavity, above the vagina, and over the bladder
Body – upper 2/3
Cervix – bottom 1/3; surrounds cervical orifice

43. Layers of Uterine Wall Endometrium Myometrium Perimetrium
Endometrium and myometrium change extensively during pregnancy
Endometriosis

46. Vagina Extends from the uterus to the outside of the body
Conveys uterine secretions
Receives the penis during intercourse
Provides a channel for offspring during birth
Extends up and back into pelvic cavity, posterior to bladder and urethra, anterior to rectum
Hymen

47. Vulva - Structure
External accessory structure of the female reproductive system
Surrounds openings of urethra and vagina
Labia majora
Mons pubis
Labia minora
Clitoris
Vestibule
Vestibular glands

49. Female Sex Hormones
Estrogen – produced by the ovaries to stimulate enlargement of accessory organs and external reproductive structures, develops and maintains secondary sexual characteristics:
Development of breasts and ducts of mammary glands
Increased deposition of adipose in breasts, thighs, and buttocks
Increased skin vascularity
Progesterone – produced by ovaries to promote uterine changes during reproductive cycle, affects mammary glands, and helps regulate release of FSH and LH
Androgens – increase hair in pubic and axillary regions; formed by adrenal cortex in females

50. Female Reproductive Cycle
Aka menstrual cycle
Consists of regular, recurring changes in the uterine lining
Culminates in menses, or menstrual bleeding
Begins around age 13 and continues until middle age
Menopause

52. Mammary Glands
Accessory organs specialized to secrete milk following pregnancy
Modified sweat glands
Found in breasts over the pectoralis major muscles