Pelvis and Contents

1
Pelvis and Contents

• Reproductive Organs

2
Bones of the Pelvis

• Pelvic / hip girdle
• Function
• Attaches the lower limbs to spine
• Supports the viscera of the pelvis
• Transmits the weight of the upper body
• Contents
• Paired hip bones (coxal bone)
• Unite with each other anteriorly and with the
  sacrum posteriorly
• Bony pelvis
• Os coxae, sacrum and coccyx

pg 366
Use lab work to learn bony landmarks of pelvis
3
Os Coxae

• Each pelvic bone during childhood
• Ilium
• Superior region
• Ishium
• Posteroinferior region
• Pubis
• Anterior region

pg 366, 381
pg 380
4
True and False Pelves

• Separated by the pelvic brim
• False Pelvis
• Superior to the pelvic brim
• Iliac blades
• contains abdominal organs
• attachment for muscles and ligaments to body wall
• True Pelvis
• Inferior to the pelvic brim
• Space contains
• part colon
• rectum
• bladder
• uterus/ovaries (females)

pg 366
5

• Pelvic Diaphragm
• levator ani and coccygeus muscles
• Supports pelvic organs
• Seals inferior opening of bony pelvis
• Lifts to help release feces during defecation

pg 392
6
Sexual Dimorphism

• Males
• Cavity is narrow, deep
• Smaller inlet and outlet
• Bones heavier, thicker
• Pubic angle more acute
• Ischial tuberosities longer, face more medially
• Coccyx less moveable, more curved

• Females
• Tilted forward
• Cavity is broad, shallow
• Pelvic inlet oval and outlet round
• Bones are lighter, thinner
• Pubic angle larger
• Ischial tuberosities shorter, more everted
• Coccyx more moveable, straighter

7
Sexual Dimorphism
Female
Male
pg 386
8
Perineum

• Anus and external genitalia
• Diamond shaped
• Pubic symphysis anteriorly
• Ischial tuberosities laterally
• Coccyx posteriorly
• Females
• External genitalia
• Anus
• Males
• Scrotum
• Root of penis
• Anus

pg 443-4
9
Embryonic Development of the Sex Organs

• Begin at week 5 as masses of gonadal ridges
• Develop into the gonads
• Sexually indifferent!
• Both ducts are present in embryo, but only one
  develops
• Male
• Mesonephric (Wolffian) ducts
• Vas deferens, epididymis
• Female
• Paramesonephric (Müllerian) ducts
• Uterus, oviduct, vagina

10
External genitalia develops from same structures

• Embryonic structure Male Female
• Labioscrotal swelling Scrotum Labia major
• Urethral folds Penile Urethra Labia
  minor
• Genital tubercle Penis Clitoris

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Descent of the Gonads

• Male Development
• Testes partially descend at 3 months, finish at 7
  months
• Enter the scrotum
• Vaginal process
• Outpocketing of the peritoneal cavity
• Eventually closes off
• Forms tunica vaginalis
• Gubernaculum
• Fibrous cord
• Extends from the testis to floor of scrotal sac
• Final teste descent
• Shortening of gubernaculum
• Increase in intra-abdominal pressure
• Testosterone stimulation

12
Descent of the Gonads

• Female Development
• Descend only into the pelvis
• Broad ligament blocks further descent
• Gubernaculum
• Guides ovaries
• Attached to labia major
• Becomes
• Round ligament of the uterus (inferior portion)
• Ovarian ligament (superior portion)
• Vaginal process
• Outpocketing of peritoneum guides descent

13
Puberty

• Between ages 10 and 15
• Reproductive organs grow to their adult size
• Reproduction becomes possible
• Changes occur due to the increase in reproductive
  hormones in each individual
• Testosterone in males
• Estrogens in females

14
Dimporhism at Puberty

• Males
• Age 13
• Enlargement of the testes and scrotum
• Secondary sex characteristics
• Appearance of pubic, axillary, and facial hair
• Enlargement of larynx
• Oily skin
• Increase in body size and musculature

• Females
• Age 11
• Budding of breasts
• Secondary sex characteristics
• Increase in subcutaneous fat (hips and breasts)
• Widening and lightening of the bones
• Oily skin
• Hair in pubic and axillary region
• Menarche
• Menstruation
• Happens 1-2 years later

15
Reproductive System

• Overall function is to produce offspring
• Genitalia sex organs
• Primary Gonads
• Ovaries, testes
• Produce the sex cells / gametes
• Sperm, eggs
• Secrete sex hormones
• Secondary Accessory
• Glands, ducts, external genitalia
• Nourish and transport of gametes

16
Male Reproductive System
17
Male Reproductive System

• Primary sex organ
• Gonads testes
• Lie in the scrotum
• Sperm-producing
• Secondary sex organs
• External Genitalia
• Penis
• Scrotum
• Ducts
• Epididymis
• Efferent ductules
• Duct of epididymis
• Vas deferens
• Ejaculatory duct
• Urethra
• Glands
• Seminal vesicle
• Prostate
• Bulbourethral

pg 365
18
Scrotum

• Sac of skin and fascia
• Hangs at the root of the penis
• Contains the testes
• Septum in midline divides right and left halves
• Muscles
• Dartos
• Inside skin of scrotum
• Smooth muscle
• Responsible for wrinkling of scrotal skin (warms)
• Cremaster
• Extends into scrotum from spermatic cord
• Fibers from internal oblique
• Skeletal muscle
• Responsible for elevating and lowering the testes
  (warming and cooling)

19
Testes

• Lie within the scrotum
• Tunica vaginalis
• Light sac partly covering each testes
• Tunica albuginea
• Fibrous capsule of the testes
• Deep to tunica vaginalis
• Divides testes into lobules
• Lobules contain seminiferous tubules

pg 408
20
Reproductive Duct System

• Seminiferous tubules
• sperm factories
• Location of spermatogenesis
• Converge into.
• Tubulus rectus
• Straight tube that conveys sperm into.
• Rete testis
• Lead to the
• Efferent ductules
• Lead to epididymis .

pg 408
21
Reproductive Duct System

• Epididymis
• Site of sperm maturation
• Smooth muscle layer leads to ejaculation
• Contains
• Head
• Contain the efferent ductules
• tube from rete testes to duct of epididymis
• Ciliated simple columnar epithelium
• Body and Tail
• Duct of epididymis
• Highly coiled
• Leads into the vas deferens
• Pseudostratified columnar epithelium with
  stereocilia
• Resorb testicular fliud
• Transfer nutrients and secretions to sperm stored
  in the epididymis

22
Reproductive Duct System

• Vas Deferens (Ductus Deferens)
• Stores and transports sperm during ejaculation
• Runs from epididymis to ejaculatory duct
• ED then runs within the prostate gland and
  empties into the prostatic urethra
• Layers
• Pseudostratified epithelium
• Lamina propria
• Thick muscularis
• Adventitia
• Vasectomy
• Cut vas deferns, close off ends
• Sperm STILL produced, but cannot exit the body
• Reversible sometimes!

23
Reproductive Duct System
pg 235

• Spermatic Cord
• Collective name for structures associated with
  the scrotum
• Passes through inguinal canal
• Includes
• Vas Deferens
• Testicular arteries and veins (pampiniform
  plexus)
• Lymphatic vessels
• Cremaster muscle fibers
• Nerves

24
Reproductive Duct System
pg 408
25
Reproductive Duct System
pg 365
26
Cell Division

• Mitosis
• Events in which replicated DNA of original cell
  is divided into 2 new cells
• Cell division with chromosome duplication and
  division ?2 daughter cells parent
• Have Diploid 2n number of chromosomes
• Occurs in body (somatic) cells
• Meiosis Reductional division
• Events that reduce the number of chromosomes (1/2
  of the parent)
• Have Haploid n number of chromosomes
• Occurs in sex cells

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Spermatogenesis

• Production of sperm
• Stages
• Stem cells Spermatogonia (2n)
• Mitosis
• Formation of 2 daughter cells
• Type A become precursor cells (2n)
• Type B become primary spermatocytes (2n)
• Meiosis
• Primary spermatocytes undergo Meiosis I
• 2 secondary spermatocytes (n)
• Secondary spermatocytes undergo Meiosis II
• 4 spermatids (n)
• Spermiogenesis
• Spermatids differentiate into sperm
• Sperm cell (spermatozoan)
• Head (acrosome), tail and midpiece
• Controlled by FSH (pituitary gland) and
  testosterone (testes)

28
Spermatogenesis
29
Within Seminiferous Tubules

• Sustentacular cells (Sertoli cells)
• Surround the spermatogenic cells in the lumen
• Provide nutrients to spermatogenic cells
• Move cells toward tubule lumen
• Secrete testicular fluid
• Phagocytize cytoplasm shed by developing
  spermatids
• Secrete Androgen-binding protein (concentrates
  testosterone)
• Secrete Inhibin (hormone slows rate of sperm
  production)
• Blood-testis barrier
• In tight junctions between the sustentacular
  cells
• Prevent escape of membrane antigens from sperm
  into the bloodstream

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Within Seminiferous Tubules

• Myoid cells
• Layers of smooth muscle cells
• Contract to squeeze sperm thru tubules and out of
  testis
• Interstitial cells (Leydig cells)
• Make and secrete male sex hormone (androgens)
• In CT between tubules

31
Accessory Glands

• Seminal Vesicles (2)
• Lie on posterior surface of the bladder
• Joins the vas deferens to form an ejaculator duct
• Contracts during ejaculation to empty
• Secretion contains
• Fructose to nourish sperm
• Prostaglandins to stimulate contraction of the
  uterus
• Suppress immune response in females
• Sperm motility enhancers
• Enzymes that clot ejaculated semen in vagina,
  then liquefy it so sperm can swim out

pg 365
32
Accessory Glands

• Prostate gland
• Inferior to bladder, anterior to rectum
• Encircles the first part of the urethra
• Contracts during ejaculation
• Secretion contains
• Substances that enhance sperm motility
• Enzymes that liquefy ejaculated sperm
• Bulbourethral gland (2)
• Inferior to prostate gland
• Within urogenital diaphragm
• Empties into spongy urethra
• Produce a mucus
• Neutralize urine in urethra
• Lubricate semen for passage

pg 365
33
Penis

• Male external genitalia
• Delivers sperm into the female reproductive tract
• Anatomy
• Root
• Attached end
• Crura
• Anchored to pubic arch, covered by
  ischiocavernosus muscle
• Bulb
• Secured to urogenital diaphragm
• Body / Shaft
• Free not attached
• Glans penis
• Enlarged tip
• Prepuce / Foreskin
• Loose cuff around glans
• Spongy urethra
• Tube within penis

pg 439
34
Penis

• Erectile bodies
• 3 cylindrical bodies around the spongy urethra
• Thick tube covered by DCT
• Filled with smooth muscle, CT, and vascular
  spaces
• Corpus spongiosum
• Midventral erectile body
• Distally forms the glans penis
• Proximally forms the bulb of the penis
• Corpora cavernosa
• Paired, dorsal erectile bodies
• Proximal ends are the crura of the penis (crus)
• Covered by ischiocavernosus muscle
• Make up most of the mass of the penis

pg 439
35
Penis Innervation and Vasculature

• Arterial supply
• Branches of internal pudendal
• Innervation
• Branches of pudendal from sacral plexus provides
  sensory innervation
• Parasympathetic
• Engorgement of blood in erectile bodies
  erection
• Sympathetic
• Contraction of smooth muscle in ducts and glands
  and bulbospongiosum muscle ejaculation
• Autonomic from inferior hypogastric plexus

pg 449
pg 447
36
Female Reproductive System
37
Female Reproductive System

• Primary Sex Organs
• Ovaries gonads
• Secondary Sex Organs
• External Genitalia vulva
• Labia major minor
• Mons pubis
• Clitoris
• Ducts
• Uterine tube oviducts
• Vagina
• Glands
• Greater vestibular gland

pg 365
38
Anatomy

• Ovaries (2)
• Produce and store ova (eggs)
• Produce estrogen
• Tunica albuginea
• Fibrous capsule that surrounds the ovary
• Germinal epithelium
• Covers the tunica albuginea
• Mesothelium

pg 365
39
Anatomy

• Ovaries are retroperitoneal
• Surrounded by peritoneal cavity and held in place
  by mesentery and ligaments from peritoneum
• Ligaments
• Broad ligament
• Supports uterus and oviducts
• Suspensory ligament
• Attaches ovaries to lateral pelvic wall
• Ovarian ligament
• Anchors the ovary to the uterus medially
• Round ligament
• Part of broad ligament
• Attaches uterus to labia majorum

pg 365
40
Oogenesis production of eggs (ova)

• Stem cells oogonia undergo Mitosis
• All of females oogonia produced while fetus
• Oogonia become oocytes
• Oogonia begin Meiosis I are called primary
  oocytes (2n)
• Meiosis I is stalled before birth and until
  ovulation
• During ovulation, Meiosis I completed and Meiosis
  II begins
• Once Meiosis II begins, primary oocytes now
  called secondary oocytes (n)
• Meiosis II is completed when sperm penetrates
  plasma membrane of the egg
• When Meiosis II is completed, secondary oocyte is
  now called ovum (egg)
• Meiosis II results in 4 daughter cells
• 1 ovum and 3 polar bodies (degenerate)

41
Oogenesis
Begins and stalls until ovulation
Meiosis 2 completes upon sperm penetration of
secondary oocyte
42
Uterine Tubes

• Also called oviducts, fallopian tubes
• Begins laterally near ovary and ends medially at
  uterus
• 3 parts
• Infundibulum
• Lateral, funnel shaped portion
• Fimbrae on edges
• Ampulla
• Medial to infundibulum
• Expanded portion
• Site where fertilization occurs
• Isthmus
• Medial part of the tube
• Visceral Peritoneum, Smooth Muscle, Ciliated
  simple columnar epithelium

pg 414
43
Movement of Ova

• Through the oviduct
• Receives oocyte after ovulation
• Peristaltic waves
• Cilia lining tube
• Contains cells to nourish ova
• Ectopic pregnancy
• Implantation of embryo outside of the uterus

44
Uterus

• Function
• Receive, retain, nourish fertilized egg (zygote)
• 3 layers of wall
• Perimetrium (outer)
• Myometrium (middle)
• Endometrium (inner)
• Portions
• Body
• Fundus
• Isthmus
• Location
• Anterior to rectum
• Posterosuperior to bladder

pg 414
45
Cervix

• Location
• Below the isthmus of the uterus
• Considered the narrow neck of the uterus
• Projects into the vagina
• Function
• Keeps uterus closed and fetus within it during
  pregnancy (collagen)

pg 414
46
Vagina

• Location
• Inferior to the uterus
• Anterior to the rectum
• Posterior to the urethra and bladder
• Birth canal
• 3 layers
• Adventitia
• Muscularis
• Mucosa
• Rugae
• Vaginal orifice
• Hymen
• Extension of mucosa
• Incomplete wall / diaphragm

pg 414
47
Female External Genitalia Vulva

• Mons pubis
• Rounded pad over the pubic symphysis
• Labia
• Major
• Fatty skin folds with hair
• Minor
• Smaller, hairless folds inside major
• 3 parts
• Vestibule
• created by labia minor
• opening for urethra and vagina
• Central tendon
• Perineal body
• Fourchette
• Junction of labia minor

pg 443, 439
48
Female External Genitalia Vulva

• Clitoris
• Superior to vestibule
• Composed of erectile tissue
• Homologous to the penis
• Components
• Crura
• Prepuce
• Corpus cavernosa
• No corpus spongiosum
• Bulbs of vestibule
• Engorge with blood to help grip the penis
• Greater vestibular glands
• Either side of vaginal opening
• Secrete mucus to make intercourse possible

pg 443, 439
49
Vasculature and Innervation
pg 432

• Vasculature
• Uterine arteries from internal iliac and arcuate
  branches uterus
• Ovarian arteries from abdominal aorta and ovarian
  branches of uterine arteries ovaries
• Innervation
• Branches of Pudendal nerve (hypogastric plexus
  pelvic splanchnic nerves)

pg 317
50
Fertilization sperm meets egg
Path of sperm Seminiferous tubules?tubulus
rectus ?rete testis?efferent ductules? duct of
epididymis? vas deferens? ejaculatory duct ?
urethra?females vagina? uterus?oviduct
Path of egg ovary?peritoneal cavity?infundibulum
(oviduct) ?oviduct
The meeting Sperm egg meet in uterine tube
?sperm penetrates egg fertilization Zygote?uteru
s for implantation in uterine wall