A

Reproductive Anatomy and Physiology

Reproductive System Anatomy and Gametogenesis

Upcoming Schedule

  • Today: Focus on reproductive anatomy.
  • Wednesday: Reproductive physiology and pregnancy.
  • Next Monday: Reproductive diseases and contraceptives.
  • Next Wednesday: Practical review.
  • Monday, May 5th: Practical 4 (last day of class).

Overview of Reproductive System

  • Gonads:
    • Primary sex organs.
    • Testes in males and ovaries in females.
    • Produce gametes and hormones.
  • Gametes:
    • Functional reproductive cells.
    • Oocytes (eggs) in females and sperm in males.
  • Ducts: Receive and transport gametes.
  • Accessory Glands: Secrete fluid into ducts.
  • Perineal Structures: External genitalia.

Functional Differences

  • Females: Produce 1 gamete per month.
  • Males: Produce millions of gametes per day.

Analogues

  • Organs that develop from the same embryonic tissue in males and females and share functions.
  • Important to know the chart of analogous structures.

Male Reproductive Anatomy

  • Key Structures to Know:
    • Ureter
    • Urinary bladder
    • Pubic symphysis
    • Ductus deferens
    • Seminal gland (seminal vesicle)
    • Ejaculatory duct
    • Prostate gland
    • Prostatic urethra
    • Bulbourethral gland
    • Crus of penis
    • Corpora cavernosa
    • Corpus spongiosum
    • Scrotum
    • Epididymis
    • Testis
    • Penis
    • Body of penis
    • Glans
    • External urethral orifice
    • Bulb of penis
    • Urogenital diaphragm
    • Spongy urethra
    • Prepuce

Female Reproductive Anatomy

  • Key Structures to Know:
    • Urinary bladder
    • Pubic symphysis
    • Urethra
    • Clitoris
    • External urethral orifice
    • Labium minora
    • Labium majora
    • Ureter
    • Uterine tube
    • Ovary
    • Fimbriae of uterine tube
    • Cervix
    • Rectum
    • Vagina
    • Anus
    • Body of clitoris
    • Crus of clitoris
    • Mons pubis
    • Glans of clitoris
    • Prepuce
    • Urethral opening
    • Vestibule
    • Hymen
    • Openings for greater vestibular glands
    • Vestibular bulb
    • Greater vestibular gland
    • Endometrium
    • Myometrium
    • Perimetrium
  • Additional Structures:
    • Ovarian blood vessels
    • Ovarian artery
    • Ovarian vein
    • Suspensory ligament
    • Infundibulum
    • Ovarian ligament
    • Broad ligament
    • Uterine artery
    • Uterine vein
    • Rugae
    • External os
    • Fornix
    • Vaginal Wall
    • Wall of uterus
    • Tunica albuginea
    • Medulla
    • Hilum
    • Germinal epithelium
    • Cortex

Mammary Gland Anatomy

  • Key Structures:
    • Rib
    • Pectoral Fat Pad
    • Intercostal muscles
    • Pectoralis minor
    • Pectoralis major
    • Mammary gland
    • Lobe
    • Lactiferous sinus
    • Alveoli
    • Nipple
    • Areola
    • Lactiferous ducts
    • Suspensory ligaments

Gametogenesis

  • Formation and development of gametes (sperm or eggs).
  • Begins with meiosis.
    • Meiosis 1 and 2.
    • Diploid to haploid.

Female Reproductive: Ovaries and Ovarian Follicles

  • Ovaries = primary organs.
  • Ovarian follicles: Small fluid-filled sacs inside of the ovaries that contain immature eggs (oocytes).
    • Support and protect the egg.
    • Each oocyte is surrounded by follicle cells
    • There are 7 different stages of development for the follicle that you need to know.

Follicle Stages

Stage 1 - Primordial Follicle

  • Earliest stage of egg in ovary.
  • Primary oocyte surrounded by single layer of flat cells.
  • Females are born with approximately millions of primordial follicles. Number decreases throughout lifespan.
  • Stays inactive until puberty.

Stage 2 - Primary Follicle

  • Formed from primordial follicle.
  • Still contains primary oocyte.
  • Now surrounded by granulosa cells.

Stage 3 - Secondary Follicle

  • Formed from primary follicle.
  • Still primary oocyte but with a lot more cells and layers around it now.

Stage 4 - Mature Follicle

  • Oocyte fully developed.
  • Much larger.
  • Secondary oocyte now.
  • Prepping for ovulation stage.

Stage 5 - Ovulation

  • Mature follicle will rupture and release the oocyte, called ovulation.
  • Egg released into uterine tubes.
  • This is the stage where pregnancy is most likely.

Stage 6 - Corpus Luteum

  • Whatever is left behind in follicle after ovulation becomes corpus luteum.
  • Corpus luteum secretes progesterone to help support potential pregnancy.

Stage 7 - Corpus Albicans

  • Breakdown of corpus luteum forms corpus albicans.
  • This is scar tissue formed if pregnancy does not occur, as there is no need for the corpus luteum.
  • Restart cycle.

Oogenesis

  • Primary oocyte to secondary.
  • Before birth:
    • Oogonia divide to form primary oocytes.
  • Childhood:
    • Ovaries inactive.
  • Puberty and after:
    • The stages of development from the past 7 slides occur until menopause.

Male Reproductive System

Male Reproductive Functions

  • Primary organs = testes

4 Major Functions of Male Accessory Glands

  1. Activating spermatozoa
  2. Providing nutrients spermatozoa need for motility
  3. Propelling spermatozoa and fluids along reproductive tract
    • Mainly by peristaltic contractions
  4. Producing buffers
    • To counteract acidity of urethral and vaginal environments

Spermatogenesis

  • Process of sperm development.
  • Does not start until puberty.
  • 5 stages (know all)

5 Stages/Cell Types in Order

  1. Spermatogonia
    • Stem cells that divide by mitosis.
    • Form 1 new stem cell and 1 primary spermatocyte.
  2. Primary spermatocyte
    • Undergo meiosis 1 to form next cell type.
  3. Secondary spermatocytes
    • Undergo meiosis 2
  4. Spermatids
    • Differentiate into step 5
  5. Sperm
    • Enter fluid in lumen

Overview of Sperm Anatomy

  • Acrosome cap
  • Nucleus
  • Mitochondria
  • Head
  • Midpiece
  • Tail