1 / 60

REPRODUCTIVE SYSTEM

REPRODUCTIVE SYSTEM. REPRODUCTIVE SYSTEM: Design. Not for Homeostasis; Instead to Perpetuate the Species Sexual Reproduction Results in Genetic Variability Internal Fertilization & Gestation One Offspring per Pregnancy is Typical . REPRODUCTIVE SYSTEM: Functions.

barton
Download Presentation

REPRODUCTIVE SYSTEM

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. REPRODUCTIVE SYSTEM

  2. REPRODUCTIVE SYSTEM: Design • Not for Homeostasis; Instead to Perpetuate the Species • Sexual Reproduction Results in Genetic Variability • Internal Fertilization & Gestation • One Offspring per Pregnancy is Typical

  3. REPRODUCTIVE SYSTEM: Functions • Production & Support of Gametes • Formation, Transport & Delivery of Sperm • Formation & Transport of Ova • Protect & Support Developing Embryo, and Nourish Fetus • Deliver the Fetus

  4. REPRODUCTIVE SYSTEM: Overview of Anatomy • Reproductive Organs • Associated Ducts • Accessory Glands • External Genitalia

  5. MALE ANATOMY: TESTES • From the Greek for “witness” (e.g., testify) • Essential organs of reproduction in the male (Male Gonad) • Site of sperm production • Suspended in scrotum by spermatic cord • Oval, ~4.5 cm long, 10.5 - 14 gms

  6. MALE ANATOMY: SCROTUM • Pouch of skin and fascia evaginated from anterior abdominal wall • Subdivided into two lateral compartments, indicated by Raphe (Ridge) • Houses testes, keeps them cool (93F) • Cremaster muscle brings testes closer to body • Dartos muscle causes wrinkling

  7. MALE ANATOMY: TESTES • Develop initially in abdominal cavity (retroperitoneally) • Descend into scrotum • Begins in 7th month of gestation • Pass through inguinal canal • Should be in scrotum by birth Continued ...

  8. MALE ANATOMY: TESTES CONTINUED • Seminiferous tubules: Sites of sperm production • Interstitial Cells: Secrete Testosterone • Efferent ductules: Carry sperm from testes • Epididymis: • Store sperm • Site of sperm maturation (2 weeks) Continued ...

  9. MALE ANATOMY: SPERMATIC CORD • Contains structures passing to and from testes • Coverings derived from abdominal wall • Contents include: • Vas deferens • Spermatic artery and vein • Spermatic nerve • Lymph vessel

  10. MALE ANATOMY: VAS (DUCTUS) DEFERENS • Carries sperm from epididymis to seminal vesicle • Passes through inguinal canal into body cavity • Crosses surface of urinary bladder • Joins with duct of seminal vesicle to form the ejaculatory duct • Vasectomy

  11. MALE ACCESSORY GLANDS: SEMINAL VESICLES • Paired structures posterior to urinary bladder • Secrete ~60% of seminal fluid • Fluid is sugary, alkaline • Rich in carbohydrates, Vitamin C • Nourishes sperm • Enhances motility

  12. MALE ACCESSORY GLANDS : PROSTATE GLAND • Located inferior to urinary bladder, anterior to rectum • Surrounds prostatic urethra • Secretes ~25% of seminal fluid • Enzymes to Liquify Semen

  13. MALE ACCESSORY GLANDS : BULBOURETHRAL GLANDS • Also called Cowper’s glands • Lateral to membranous urethra • Secrete a drop of alkaline mucus • Cleans, lubricates urethra • Neutralizes acidic urine • Does not contribute towards semen

  14. MALE ANATOMY: PENIS • Male copulatory organ • Functions to introduce sperm into female • Consists of three erectile bodies • Two corpora cavernosa • One corpus spongiosum

  15. MALE ANATOMY: PENIS • Corpus spongiosum • Surrounds penile (spongy) urethra • Forms 1/3 of shaft • Distal end forms glans penis;Urethral orifice opens through glans • Proximal end forms bulb of penis Continued ...

  16. MALE ANATOMY: PENIS CONTINUED • Corpora cavernosa • Paired, lie laterally • Form 2/3 of shaft • Prepuce (foreskin): • Covers glans penis • Removed by circumcision

  17. MALE PHYSIOLOGY: SPERMATOGENESIS • Occurs in seminiferous tubules • Spermatogonia divide mitotically • One Spermatocyte eventually gives rise to Four Sperm via meiosis • Y Sperm are Smaller, Faster, Prefer Alkaline Environment • X Sperm are Larger, Stronger, Prefer Acidic Environment

  18. MALE SEXUAL RESPONSE • Erection • Arteries dilate, increasing blood in spongy tissue • Constricts veins, causes erection • Ejaculation (expulsion) • Semen passes through urethra • Contractions of urethra & penile musculature

  19. MALE HORMONAL CONTROLS • Gonadotropic Hormones • Follicle Stimulating Hormone (stimulates sperm production) • Luteinizing Hormone or ICSH (stimulates testes to secrete testosterone) • Testosterone (Male Sex Hormone) • Male Secondary Sex Characteristics

  20. FEMALE ANATOMY: OVARY • Female Gonad • All ova arrested at prophase I at birth • Approximately 400,000 total • Only about 400 ever reach maturity • Paired, oval, almond sized • Supported by ligaments

  21. FEMALE ANATOMY: UTERINE (Fallopian) TUBES • Site of Fertilization • Paired, ~10 cm long • Attach to uterus, one on each side • Intramural Portion: Within uterus • Isthmus: Narrow portion adjacent to uterus • Ampulla: Long, wide portion • Infundibulum: Funnel-shaped end with branches, fimbriae, that drape over ovary • Transport via Cilia & Peristalsis

  22. FEMALE ANATOMY: UTERUS • Usually unpaired; hollow, muscular, pear-shaped organ • Receives uterine tubes, empties into vagina • Site of Implantation & Development • Supported by ligaments: • Broad ligament: Double layer of peritoneum • Round ligament: Passes through inguinal canal

  23. FEMALE ANATOMY: UTERUS continued • Uterine wall has three layers • Perimetrium (broad ligament): Peritoneum • Myometrium: Thick layer of smooth muscle • Endometrium: • Epithelial layer • Undergoes cyclic changes in response to hormones • Endometriosis

  24. FEMALE ANATOMY: UTERUS • Fundus: Arches above entry of uterine tubes • Body: Large triangular lumen • Isthmus: Narrowed region • Cervix: • Most inferior portion • Extends down into vagina

  25. FEMALE ANATOMY: VAGINA • Functions: • Receives penis during intercourse • Passage for removal of menstrual debris • Serves as a birth canal • Located between urethra and rectum • Lined with stratified squamous E.T. • Acidic environment (Resident Bacteria)

  26. FEMALE ANATOMY: VAGINA continued • Fornix: Circular recess around cervix; upper portion of vagina • Hymen: • Fold of mucous membrane • Does NOT signify virginity! • Bartholin’s glands: • Distal End Vagina • Homologous to Cowper’s glands • Very little secretion (mucus)

  27. FEMALE ANATOMY: VULVA (External Genitalia) • Mons pubis: Fatty mound • Labia majora: Outer Folds of skin, Homologous to scrotum • Labia minora: Inner folds, Encircle clitoris, forming prepuce • Clitoris: Homologous to penis, corpora cavernosa

  28. FEMALE ANATOMY: CLITORIS • Foreskin or Prepuce • Function – Sexual Pleasure • Orgasm controlled by Sympathetic Division of ANS

  29. FEMALE ANATOMY: BREASTS • Structurally – Integument • Functionally – Reproductive • Colostrum • Breast Milk

  30. HORMONAL CONTROL: ADULT FEMALE • Four hormones involved: • FSH and LH (from pituitary) • Target ovaries • Follicles w/ova grow & mature • Ovaries secrete: • Estrogen and progesterone (from ovaries) • Target uterus • Endometrium thickens & secretes

More Related