Introductory Anatomy of Digestive System

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Introductory Anatomy of Digestive System

• NYUNDO Martin, MD, MMed (Surgeon)
• Lecturer
• Dpt of Surgery and Dpt of Clinical Anatomy
• FACMED-NUR

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General considerations

• Digestive system is a series of hollow organs
  joined in a long, twisting tube from the mouth to
  the anus and other organs that help the body
  break down and absorb food
• ?The main organs are Mouth and pharynx,
  Oesophagus Stomach, Small and Large
  intestines,Appendix and Anus
• ? Accessory organs Salivary glands, Liver,
  Gallbladder, Pancreas

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General considerations contd

• The gastrointestinal tract has a uniform general
  histology.The GI tract can be divided into 4
  concentric layers
• Mucosa is the innermost layer this layer comes
  in direct contact with the food (or bolus), and
  is responsible for absorption and secretion,
  important processes in digestion.
• Submucosa
• Muscularis externa (the external muscle layer)
• Adventitia or serosa

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• Accessory organs
• The liver secretes bile into the small intestine
  via the bile duct, employing the gallbladder as a
  reservoir. Apart from storing and concentrating
  bile, the gallbladder has no other specific
  function.
• The pancreas secretes an isosmotic fluid
  containing bicarbonate, which helps neutralize
  the acidic chyme, and several enzymes into the
  small intestine. Both of these secretory organs
  aid in digestion

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General considerations contd

• Abdomen
• The abdomen is the part of the trunk between the
  thorax and the pelvis
• It is a flexible, dynamic container, housing most
  of the organs of the digestive system and part of
  the urogenital system.
• Containment of the abdominal organs and their
  contents is provided by
• musculoaponeurotic walls anterolaterally,
• diaphragm superiorly,
• muscles of the pelvis inferiorly,
• lumbar vertebral column in the posterior.

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• The abdomen encloses and protects its contents
  while allowing the flexibility between the more
  rigid thorax and pelvis required by respiration,
  posture, and locomotion.
• Through voluntary or reflexive contraction, its
  muscular roof, anterolateral walls, and floor can
  raise internal (intra-abdominal) pressure to aid
  expulsion from the abdominopelvic cavity or from
  the adjacent thoracic cavity, expulsion of air
  from the thoracic cavity (lungs and bronchi) or
  of fluid (e.g., urine or vomitus), flatus, feces
  from the abdominopelvic cavity.

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General considerations contd

• Peritoneum and Peritoneal Cavity
• The peritoneum is a continuous, glistening and
  slippery transparent serous membrane. It lines
  the abdominopelvic cavity and invests the
  viscera.
• The peritoneum consists of two continuous layers
  the parietal peritoneum, which lines the internal
  surface of the abdominopelvic wall, and the
  visceral peritoneum, which invests viscera such
  as the stomach and intestines.

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• The peritoneal cavity is a potential space of
  capillary thinness between the parietal and
  visceral layers of peritoneum.
• It contains no organs but contains a thin film of
  peritoneal fluid, which is composed of water,
  electrolytes, and other substances derived from
  interstitial fluid in adjacent tissues.
• Peritoneal fluid lubricates the peritoneal
  surfaces, enabling the viscera to move over each
  other without friction and allowing the movements
  of digestion.

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• In addition to lubricating the surfaces of the
  viscera, the peritoneal fluid contains leukocytes
  and antibodies that resist infection.
• Lymphatic vessels absorb the peritoneal fluid.
• The peritoneal cavity is completely closed in
  males however, there is a communication pathway
  in females to the exterior of the body through
  the uterine tubes, uterine cavity, and vagina.
  This communication constitutes a potential
  pathway of infection from the exterior.

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General considerations contd

• Diaphragm
• The diaphragm is a double-domed musculotendinous
  partition separating the thoracic and abdominal
  cavities.
• Its mainly convex superior surface faces the
  thoracic cavity, and its concave inferior surface
  faces the abdominal cavity.

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• The diaphragm is the chief muscle of inspiration.
• It descends during inspiration however, only its
  central part moves because its periphery, as the
  fixed origin of the muscle, attaches to the
  inferior margin of the thoracic cage and the
  superior lumbar vertebrae.
• Orifices vena caval foramen, esophageal hiatus
  and aortic hiatus.

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Esophagus

• First part of the digestive tract, that conveys
  food from the pharynx to the stomach it is
  about 25 cm long and 2 cm of diameter.
• Is divided into three anatomical parts
• cervical (superior), thoracic (middle) and
  abdominal (inferior).
• The esophagus
• Follows the curve of the vertebral column as it
  descends through the neck and mediastinum in the
  median partition of the thoracic cavity.
• Has internal circular and external longitudinal
  layers of muscle.

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• In its superior third, the external layer
  consists of voluntary striated muscle the
  inferior third is composed of smooth muscle, and
  the middle third is made up of both types of
  muscle.
• Passes through the esophageal hiatus in the
  diaphragm,
• Terminates by entering the stomach at the cardial
  orifice of the stomach

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Esophagus contd

• The esophagus has 2 sphincters
• A sphincter is a narrowing caused by contracted
  (tightened) muscles.
• These muscles remain contracted until the body
  sends a message for the muscles to relax. When
  the muscles of the sphincter relax, this then
  allows things to pass.
• One sphincter is at the top of the esophagus. The
  other is where the esophagus meets the stomach
  this is known as the gastro-esophageal junction.

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• The lower sphincter controls the movement of food
  into the stomach and prevents stomach acid from
  going up into the esophagus (gastro-esophageal
  reflux).
• The lining of the esophagus is very different to
  that of the stomach and stomach acid will cause
  it to become inflamed and sore if reflux does
  occur.

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Stomach

• The stomach is the expanded part of the
  alimentary tract between the esophagus and the
  small intestine.
• It is specialized for the accumulation of
  ingested food, which it chemically and
  mechanically prepares for digestion and passage
  into the duodenum.

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• RESERVOIR
• 2-3L food in adult
• 30ml in newborn
• SHAPE VARIES
• Individual build
• Respiration
• Contents
• Position assumed by individual

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Stomach contd

• Parts of the Stomach
• CARDIA
• the part surrounding the cardial orifice.
• Orifice at 7th costal cartilage L
• 2-4 cm from median at T10 or T11 level
• FUNDUS - the dilated superior part limited
  inferiorly by the horizontal plane of the cardial
  orifice.
• BODY - the major part of the stomach between the
  fundus and the pyloric antrum
• PYLORUS (Pyloric part)
• From notch - pyloric sphincter
• At L1-L3 R median plane

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Stomach contd

• The stomach has two curvatures
• Lesser curvature forms the shorter concave
  border of the stomach
• Greater curvature forms the longer convex border
  of the stomach
• Two surfaces
• Anterior
• Posterior

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Stomach contd

• Relations
• FUNDUS diaphragm
• ANT SURFACE - diaphragm, liver L lobe ant abd
  wall
• POST SURFACE - omental bursa retroperitoneal
  structures (kidney, pancreas, spleen.)
• SUPERIOR - lesser omentum gastric vessels.
• INFERIOR - greater omentum gastro-epiploic
  vessels.

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Stomach contd

• Principles of blood supply
• 2 MAJOR ART SOURCES
• Coeliac trunk
• Superior mesenteric
• VENOUS DRAINAGE
• Follow arteries
• LYMPHATIC DRAINAGE
• Follow arteries

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Stomach contd

• Venous drainage
• FOLLOW ARTS
• Drain into portal systems
• R L ? portal vein
• R GASTROEPIPLOIC (G-MENTAL) V ? superior
  mesenteric ? may enter portal v direct or join
  splenic v
• L GASTROEPIPLOIC (G-MENTAL) ? splenic vein and
  its tributariess short gastric vs.

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Venous drainage
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Lymphatic drainage

• ALL LYMPH PASSES TO COELIAC GP of pre-aortic
  nodes
• ALL LYMPH VS. ACCOMPANY ARTS along the 2 curves
• 4 MAJOR AREAS OF DRAINAGE
• LESSER CURV
• Largest drains to L gastric LNs
• R PART GREATER CURV
• Drains gastroepiploic pyloric LNs
• L PART GREATER CURV
• Drains pyl, gastoepip, pancreticosplenic LNs
• LESSER CURVE RELATED TO PYL
• Drains to R gastric LNs

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Lymphatics
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• Common lymphatics pathway
• Drain to coeliac LN ? Coeliac trunk ?cisterna
  chyli ? Thoracic duct

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Nerve supply

• PARASYMPATHETIC from ant and post vagal trunks
• SYMPATHETIC from coeliac plexus
• EFFERENT FIBRES from segments T6-T10
• VAGAL TRUNKS
• Ant ? lesser curve? hepatic duodenal branch
• Post ? lesser curve from post surface ? coeliac ?
  coeliac plexus ? post gastric branch

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Nerve supply
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3. SMALL INTESTINES

• Extent stomach to colon
• Length approximately 5m
• Parts
• Duodenum
• Jejunum
• Ileum

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DUODENUM

• The duodenum, the first and shortest (25 cm) part
  of the small intestine, is also the widest and
  most fixed part.
• The duodenum pursues a C-shaped course around the
  head of the pancreas.
• The duodenum begins at the pylorus on the right
  side and ends at the duodenojejunal junction on
  the left side. ( Treitz ligament)
• The junction usually takes the form of an acute
  angle, the duodenojejunal flexure.
• Most of the duodenum is fixed by peritoneum to
  structures on the posterior abdominal wall and is
  considered partially retroperitoneal.

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• The duodenum is divisible into four parts
• Superior (first) part short (approximately 5 cm)
  and lies anterolateral to the body of the L1
  vertebra.
• Descending (second) part longer (7-10 cm) and
  descends along the right sides of the L1-L3
  vertebrae.
• Horizontal (third) part 6-8 cm long and crosses
  the L3 vertebra.
• Ascending (fourth) part short (5 cm) and begins
  at the left of the L3 vertebra and rises
  superiorly as far as the superior border of the
  L2 vertebra.

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Superior or First Part
1
2
4
3
Descending or Second Part
Horizontal or Third Part
Fourth or Ascending Part
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Duodenum blood supply

• The arteries arise from the celiac trunk and the
  superior mesenteric artery. The celiac trunk, via
  the gastroduodenal artery and its branch,
• The veins follow the arteries and drain into the
  portal vein, some directly and others indirectly,
  through the superior mesenteric and splenic
  veins.
• The lymphatic vessels of the duodenum follow the
  arteries.

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CLINICALCORRELATES

• Duodenal ulcer
• Usual located sup aspect - 1st part
• When post, penetration may cause bleeding
  (gastroduodenal art) or erosion into head of
  pancreas
• Ant ulcers may perforate into peritoneum
  (peritonitis).

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JEJUNUM ILEUM

• Jejunum 2nd part of the small intestine, begins
  at the duodenojejunal flexure at the Treitz
  ligament where the alimentary tract resumes an
  intraperitoneal course.
• Wider, thicker-walled than ileum
• Mucous membrane thrown into circular folds with
  many longer villi
• Ileum third part of the small intestine, ends at
  the ileocecal junction, the union of the terminal
  ileum and the cecum .
• Together, the jejunum and ileum are 6 to 7 m
  long, the jejunum constituting approximately two
  fifths and the ileum approximately three fifths
  of the intraperitoneal section of the small
  intestine.

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Jejunum and ileum

• Although no clear line of demarcation between the
  jejunum and ileum exists, they have distinctive
  characteristics that are surgically important
• The jejunum and ileum can be distinguished by
  ther color, feel and their complexity of arterial
  arcades
• ? Jejum redder wall, thicker wall(feels
  full) and simple arcades
• ? Ileum thinner wall, (feels empty),
  multiple arcades

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• The mesentery is a fan-shaped fold of peritoneum
  that attaches the jejunum and ileum to the
  posterior abdominal wall
• The superior mesenteric artery supplies the
  jejunum and ileum .
• The superior mesenteric vein drains the jejunum
  and ileum.
• Specialized lymphatic vessels in the intestinal
  villi
• Blood vs. arrangement varies jej ileum

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MESENTERIC LYMPH NODES
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Large Intestine

• The large intestine is the site where water is
  absorbed from the indigestible residues of the
  liquid chyme, converting it into semisolid stool
  or feces that is stored temporarily and allowed
  to accumulate until defecation occurs.
• Extent
• Ileocaecal junction to anus about 1.5 m long
• Parts
• Caecum vermiform appendix
• Ascending, transverse descending
• Sigmoid
• Rectum anal canal

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Small large intestines
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Large Intestine contd

• The large intestine can be distinguished from the
  small intestine by
• Omental appendices small, fatty, omentum-like
  projections.
• Three teniae coli
• (1) mesocolic, to which the transverse and
  sigmoid mesocolons attach
• (2) omental, to which the omental appendices
  attach and
• (3) free (L. libera), to which neither mesocolons
  nor omental appendices are attached.
• Haustra sacculations of the wall of the colon
  between the teniae
• A much greater caliber (internal diameter).
• Mucosa
• No villi, numerous mucus cells

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Caecum

• Blind sac invested in peritoneum
• 8 cm W x 8 cm L, located in RIF
• Vermiform appendix
• Attached to posteromedial wall
• Taenia coli converge on appendix
• Ileocaecal orifice
• Opens on medial wall
• Surrounded by ileocaecal sphincter

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Caecum vermiform appendix
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Vermiform appendix

• About 8 cm long
• Arises posteromedial aspect of caecum
• About 3 cm below ileocaecal orifice
• Mesoappendix
• Connects perit. to ileum
• Appendicular art within this fold
• Commonly behind caecum or in pelvis
• Very mobile its relations are variable

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Position of the Appendix

• A retrocecal appendix extends superiorly toward
  the right colic flexure and is usually free.
• The appendix may project inferiorly toward or
  across the pelvic brim.
• The anatomical position of the appendix
  determines the symptoms and the site of muscular
  spasm and tenderness when the appendix is
  inflamed.
• The base of the appendix lies deep to a point
  that is one third of the way along the oblique
  line joining the right ASIS to the umbilicus (the
  McBuney point on the spinoumbilical line).

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Ascending colon

• Lies R lateral flank
• Extent
• Iliocaecal orifice to R colic flexure
• 15 cm long
• Peritoneum
• Cover ant both sides, fixing it to post wall

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Relations of ascending colon

• Post
• Lower pole R kidney
• Iliohypogastric ilioinguinal nerves
• Ant
• Coils of small intestines
• Parts of greater omentum

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Transverse colon

• 50 cm long
• At umbilicus level largest most mobile
• Extent
• R - L colic flexures across the abd
• L flexure more superior, acute angle less
  mobile than R flexure
• Sup transverse mesocolon suspends it
• Inf mesentery loops down to iliac crest,
  adherent to post wall of omental bursa

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Transverse colon
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Relations of the transverse colon

• Post R-L
• 2nd part duodenum, head of pancreas, small
  intestine, L kidney
• Anterosuperiorly R-L
• Liver, gb, stomach, greater omentum spleen
• Transv colon mesentery
• Attaches to body of pancreas
• Continuous with parietal peritoneum

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Descending colon

• Narrowest part of colon L lateral flank
• Extent Splenic flexure-LIF
• 30 cm long
• Peritoneum cover ant on both sides, fixing it
  to post wall
• Flexure attached to diaphragm by phrenico-colic
  ligament, that also supports the spleen

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Relations of descending colon

• Post
• Lower pole L kidney diaphragm
• Quadratus lumborum, iliacus psoas
• Peritoneal surfaces
• In contact with coils of small intestines

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Sigmoid colon

• LIF, pelvic brim - S3 ant
• 40 cm long, varies in position
• Attached to pelvic wall by an inverted V-shaped
  sigmoid mesentery
• Apex of V overlies L ureter, at bifurcation of
  common iliac v L sacroiliac joint
• Taenia coli terminate 15 cm from anus, marking
  the recto-sigmoid junction

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Relations of sigmoid colon

• Post
• Lies on L ureter common iliac vessels
• Sup
• Covered by coils of small intestine
• Inf
• Lies on urinary bladder in male
• Lies on uterus in female

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Rectum

• 12 cm long, pelvic no mesentery
• Extent
• Rectosigmoid (S3) - anorectal j
• Course from S3 curves forward, loops L as far as
  coccyx tip widens inf. into a rectal ampulla

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Relations of the rectum

• Lat coils of small int covered by peritoneum
• Inf levator ani, coccyx rectal vs
• Post sup rectal art, S3, S4 S5, symp trunk,
  lat median sacral vs lower part of sacrum,
  coccyx
• In both sexes, upper ? forms post wall of
  rectovesical pouch in ?, rectouterine in ?
• In ? sem vesicles, d deferens, bladder
  prostate in ? post wall vagina uterus

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Anal canal

• 4 cm long
• External internal sphincters
• Internal
• Involuntary (circular muscle coat)
• Upper 2/3 canal, innervated by pelvic plexus
  sympathetic stimulation contracts muscle

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Anal canal - cont

• External - lower ? of canal
• Superficial - surrounds lower part attaches to
  anococcygeal body perineal body inf. rectal n
• Deep - mid part of canal, levator ani reinforces
  essential in function
• Subcutaneous - thick ring of muscle surrounding
  anal orifice

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Blood supply of large intestine
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Clinical correlates

• Appendicitis
• Cancer of large intestines

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ACCESORY ORGANES

• Spleen
• The spleen is an ovoid organ varies considerably
  in size, weight, and shape however, it is
  usually approximately 12 cm long and 7 cm wide.
• The spleen is located in the left upper abdominal
  quadrant or hypochondrium, where it receives the
  protection of the lower thoracic cage
• The diaphragmatic surface of the spleen is
  convexly curved to fit the concavity of the
  diaphragm.

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• The anterior and superior borders of the spleen
  are sharp and often notched, whereas its
  posterior (medial) end and inferior border are
  rounded.
• It is relatively delicate and considered the most
  vulnerable abdominal organ.
• As the largest of the lymphatic organs, it
  participates in the body's defense system as a
  site of lymphocyte (white blood cell)
  proliferation and of immune surveillance and
  response.

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• The relations of the spleen are
• Anteriorly, the stomach.
• Posteriorly, the left part of the diaphragm,
• Inferiorly, the left colic flexure.
• Medially, the left kidney.
• The spleen contacts the posterior wall of the
  stomach and is connected to its greater curvature
  by the gastrosplenic ligament and to the left
  kidney by the splenorenal ligament.

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• These ligaments, containing splenic vessels, are
  attached to the hilum of the spleen on its medial
  aspect .
• The splenic hilum is often in contact with the
  tail of the pancreas and constitutes the left
  boundary of the omental bursa.

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Splenic vessels

• The splenic artery is the largest branch of the
  celiac trunk Between the layers of the
  splenorenal ligament, the splenic artery divides
  into five or more branches that enter the hilum.
• The splenic vein is formed by several tributaries
  that emerge from the hilum. With the IMV and SMV
  form the portal vein.

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• The splenic lymphatic vessels leave the lymph
  nodes in the splenic hilum and pass along the
  splenic vessels to the pancreaticosplenic lymph
  nodes
• The nerves of the spleen, derived from the celiac
  nerve plexus, are distributed mainly along
  branches of the splenic artery, and are vasomotor
  in function

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Pancreas

• The pancreas is an elongated, accessory digestive
  gland that lies retroperitoneally and
  transversely across the posterior abdominal wall,
  posterior to the stomach between the duodenum on
  the right and the spleen on the left.

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• The pancreas produces
• An exocrine secretion (pancreatic juice from the
  acinar cells) that enters the duodenum through
  the main and accessory pancreatic ducts.
• Endocrine secretions (glucagon and insulin from
  the pancreatic islets of Langerhans) that enter
  the blood.

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• The pancreas is divided into four parts head,
  neck, body, and tail.
• The head of the pancreas is the expanded part of
  the gland that is embraced by the C-shaped curve
  of the duodenum to the right of the superior
  mesenteric vessels.

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Pancreatic ducts

• The main pancreatic duct begins in the tail of
  the pancreas and runs through the parenchyma of
  the gland to the pancreatic head here it turns
  inferiorly and is closely related to the bile
  duct.
• Most of the time, the main pancreatic duct and
  the bile duct unite to form the short, dilated
  hepatopancreatic ampulla (of Vater), which opens
  into the descending part of the duodenum at the
  summit of the major duodenal papilla.

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• The sphincter of the pancreatic duct (around the
  terminal part of the pancreatic duct), the
  sphincter of the bile duct (around the
  termination of the bile duct), and the
  hepatopancreatic sphincter (of Oddi) around the
  hepatopancreatic ampulla are smooth muscle
  sphincters that control the flow of bile and
  pancreatic juice into the duodenum.

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BLOOD SUPPLY OF PANCREAS

• The pancreatic arteries derive mainly from the
  branches of the markedly tortuous splenic artery,
  which form several arcades with pancreatic
  branches of the gastroduodenal and superior
  mesenteric arteries.
• The corresponding pancreatic veins are
  tributaries of the splenic and superior
  mesenteric parts of the portal vein however,
  most of them empty into the splenic vein.

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• The pancreatic lymphatic vessels follow the blood
  vessels.
• Most vessels end in the pancreaticosplenic lymph
  nodes, that lie along the splenic artery. Some
  vessels end in the pyloric lymph nodes.
• The nerves of the pancreas are derived from the
  vagus and abdominopelvic splanchnic nerves
  passing through the diaphragm.
• The parasympathetic and sympathetic fibers reach
  the pancreas by passing along the arteries from
  the celiac plexus and superior mesenteric plexus

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LIVER

• The liver is the largest gland. It weighs
  approximately 1500 g and accounts for
  approximately 2.5 of adult body weight.
• It extends into the left hypochondrium, inferior
  to the diaphragm.
• Except for fat, all nutrients absorbed from the
  gastrointestinal tract are initially conveyed
  first to the liver by the portal venous system.
• In addition to its many metabolic activities, the
  liver stores glycogen and secretes bile.

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• Bile passes from the liver via the biliary
  ductsright and left hepatic ducts that join to
  form the common hepatic duct, which unites with
  the cystic duct to form the bile duct.
• The liver produces bile continuously however,
  between meals it accumulates and is stored in the
  gallbladder, which also concentrates the bile by
  absorbing water and salts. When food arrives in
  the duodenum, the gallbladder sends concentrated
  bile through the bile ducts to the duodenum.

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Surfaces, Peritoneal Reflections, and
Relationships of the Liver

• The liver has a convex diaphragmatic surface
  (anterior, superior, and some posterior) and a
  relatively flat or even concave visceral surface
  (posteroinferior),
• Anatomical Lobes of the Liver
• Externally, the liver is divided into two lobes
  and two accessory lobes by the reflections of
  peritoneum from its surface.
• The essentially midline plane defined by the
  attachment of the falciform ligament and the left
  sagittal fissure separates a large right lobe
  from a much smaller left lobe

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Biliary Ducts and Gallbladder

• The biliary ducts convey bile from the liver to
  the duodenum.
• Bile is produced continuously by the liver and
  stored and concentrated in the gallbladder, which
  releases it intermittently when fat enters the
  duodenum. Bile emulsifies the fat, so that it can
  be absorbed in the distal intestine.

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• Bile Duct
• The bile duct (formerly, common bile duct) forms
  in the free edge of the lesser omentum by the
  union of the cystic duct and the common hepatic
  duct. The length of the bile duct varies from 5
  to 15 cm, depending on where the cystic duct
  joins the common hepatic duct.

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Gallbladder

• The gallbladder (7-10 cm long) lies in the fossa
  for the gallbladder on the visceral surface of
  the liver.
• The pear-shaped gallbladder can hold up to 50 mL
  of bile. Peritoneum completely surrounds the
  fundus of the gallbladder and binds its body and
  neck to the liver.
• The hepatic surface of the gallbladder attaches
  to the liver by connective tissue of the fibrous
  capsule of the liver.

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• The gallbladder has three parts
• Fundus the wide end of the organ, projects from
  the inferior border of the liver and is usually
  located at the tip of the right 9th costal
  cartilage in the MCL.
• Body contacts the visceral surface of the liver,
  the transverse colon, and the superior part of
  the duodenum.
• Neck narrow and tapered directed toward the
  porta hepatis it makes an S-shaped bend and
  joins the cystic duct.

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• The cystic duct (3-4 cm long) connects the neck
  of the gallbladder to the common hepatic duct.
• The cystic duct passes between the layers of the
  lesser omentum, usually parallel to the common
  hepatic duct, which it joins to form the bile
  duct.

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Introductory Anatomy of Respiratory System

• NYUNDO Martin, MD,MMed (General Surgeon)Lecturer
• Dpt of Surgery and Dpt of Clinical Anatomy
• FACMED-NUR

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General considerations

• The respiratory system is made up of the organs
  involved in respiration
• Respiration is the act of breathing
• inhaling (inspiration) - taking in oxygen
• exhaling (expiration) - giving off carbon dioxide
• The respiratory system consists of the
• Nose, pharynx, larynx, trachea, bronchi and lungs
  
• lungs

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The pleura and airways

• The respiratory tract is most often discussed in
  terms of upper and lower parts.
• The upper respiratory tract relates to the
  nasopharynx and larynx whereas the lower relates
  to the trachea, bronchi and lungs.
• Beginning at the larynx, the walls of the airway
  are supported by C-shaped rings of hyaline
  cartilage.
• The sub-laryngeal airway constitutes the
  tracheobronchial tree.

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• The thorax includes the primary organs of the
  respiratory and cardiovascular systems
• The thorax is the superior part of the trunk
  between the neck and abdomen
• Commonly the term chest is used as a synonym for
  thorax

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• The thoracic cavity is divided into three major
  spaces
• The central compartment, or mediastinum, houses
  the conducting structures that make up the
  thoracic viscera, except for the lungs
• The lungs occupy the lateral compartments or
  pulmonary cavities that lie on each side of the
  mediastinum. Thus the majority of the thoracic
  cavity is occupied by the lungs,

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• Parts of Respiratory system
• Pharynx, Larynx
• Trachea
• Bronchi
• Lungs

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The trachea

• Located within the superior mediastinum,
  constitutes the trunk of the tree
• It bifurcates at the level of the transverse
  thoracic plane (or sternal angle) into main
  (primary) bronchi, one to each lung, passing
  inferolaterally to enter the lungs at the hila
  (hilum)

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The trachea 2

• Course
• the trachea commences at the level of the cricoid
  cartilage in the neck (C6)
• It terminates at the level of the angle of Louis
  (T4/5) where it bifurcates into right and left
  main bronchi
• Structure
• The trachea is a rigid fibroelastic structure
• Incomplete rings of hyaline cartilage
  continuously maintain the patency of the lumen.
• The trachea is lined internally with ciliated
  columnar epithelium.

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Trachea3

• Relations
• Behind the trachea lies the oesophagus
• The 2nd, 3rd and 4th tracheal rings are crossed
  anteriorly by the thyroid isthmus
• Blood supply
• the inferior thyroid
• bronchial arteries

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Bronchi

• The right main bronchus is shorter, wider and
  takes a more vertical course than the left
• The width and vertical course of the right main
  bronchus account for the tendency for inhaled
  foreign bodies to preferentially impact in the
  right middle and lower lobe bronchi.
• The left main bronchus enters the hilum and
  divides into a superior and inferior lobar
  bronchus
• The right main bronchus gives off the bronchus to
  the upper lobe prior to entering the hilum and
  once into the hilum divides into middle and
  inferior lobar bronchi.

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• the air
• enters the body through the nose or the mouth
• travels down the throat through the larynx (voice
  box) and trachea (windpipe)
• goes into the lungs through tubes called
  main-stem bronchi
• one main-stem bronchus leads to the right lung
  and one to the left lung
• in the lungs, the main-stem bronchi divide into
  smaller bronchi
• and then into even smaller tubes called
  bronchioles
• bronchioles end in tiny air sacs called alveoli

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The bronchi and bronchopulmonary segments

• Each lobar bronchus divides within the lobe into
  segmental bronchi
• Each segmental bronchus enters a
• bronchopulmonary segment
• Each bronchopulmonary segment is pyramidal in
  shape with its apex directed towards the hilum
• It is a structural unit of a lobe that has its
  own segmental bronchus, artery and lymphatics.

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• Beyond the direct branches of the lobar bronchi
  that is, beyond the segmental bronchi are from 20
  to 25 generations of branches that eventually end
  in terminal bronchioles
• Each terminal bronchiole gives rise to several
  generations of respiratory bronchioles,
• Each respiratory bronchiole provides 2-11
  alveolar ducts,
• Each of which gives rise to 5-6 alveolar sacs
  lined by alveoli.

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• The pulmonary alveolus is the basic structural
  unit of gas exchange in the lung.
• New alveoli continue to develop until about age
  8 years, by which time there are approximately
  300 million alveoli.

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LUNGS

• The lungs are a pair of cone-shaped organs made
  up of spongy, pinkish-gray tissue.

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Function

• What do lungs do?
• The lungs are the vital organs of respiration
• Their main function is to oxygenate the blood by
  bringing inspired air into close relation with
  the venous blood in the pulmonary capillaries
• The lungs take in oxygen, which all cells
  throughout the body need to live and carry out
  their normal functions
• The lungs also get rid of carbon dioxide, a waste
  product of the body's cells.

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• The lungs are separated from each other by the
  mediastinum, an area that contains the following
• heart and its large vessels
• trachea (windpipe)
• esophagus
• lymph nodes

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• The lungs are inside in a membrane called the
  pleura.
• The pleural cavitythe potential space between
  the layers of pleura contains a capillary layer
  of serous pleural fluid, which lubricates the
  pleural surfaces and allows the layers of pleura
  to slide smoothly over each other during
  respiration.
• Its surface tension also provides the cohesion
  that keeps the lung surface in contact with the
  thoracic wall consequently, the lung expands and
  fills with air when the thorax expands while
  still allowing sliding to occur, much like a
  layer of water between two glass plates.

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• Description of the lungs
• Lobes marked by fissures
• The right lung has three lobes
• The left lung has two lobes.
• Apex
• Basis (diaphragmaic surf)
• Border (ant, post and inf)
• Surfaces ( costal, mediastinal and diaphragmatic)

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• Relations of the lungs
• Heart
• Thoracic Aorta
• Esophagus
• Pulmonary artery
• Pulmonary veins
• Sup and inf vena cava

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CLINICAL CORRELATES

• Infections bronchitis
• Pneumothorax
• Entry of air into the pleural cavity, resulting
  from a penetrating wound of the parietal pleura
• Fractured ribs may also tear the visceral pleura
  and lung, thus producing pneumothorax.
• Hydrothorax The accumulation of a significant
  amount of fluid in the pleural cavity may result
  from pleural effusion (escape of fluid into the
  pleural cavity).

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• Hemothorax
• With a chest wound, blood may also enter the
  pleural cavity.
• Hemothorax results more commonly from injury to a
  major intercostal or internal thoracic vessel
  than from laceration of a lung.
• Hemopneumothorax
• If both air and fluid, (if the fluid is blood)
  accumulate in the pleural cavity, an air fluid
  level or interface (sharp line, horizontal
  regardless of the patient's position, indicating
  the upper surface of the fluid) will be seen on a
  radiograph.

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• Thoracentesis
• Sometimes it is necessary to insert a hypodermic
  needle through an intercostal space into the
  pleural cavity to obtain a sample of fluid or to
  remove blood or pus .
• To avoid damage to the intercostal nerve and
  vessels, the needle is inserted superior to the
  rib, high enough to avoid the collateral
  branches.
• Thoracic drainage chest tube

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• LUNG CANCER
• Lung cancer usually starts in the lining of the
  bronchi, but can also begin in other areas of the
  respiratory system, including the trachea,
  bronchioles, or alveoli.
• Lung cancers are believed to develop over a
  period of many years
• Nearly all lung cancers are carcinomas, a cancer
  that begins in the lining or covering tissues of
  an organ.
• What are the risk factors for lung cancer?
• A risk factor is anything that increases a
  person's chance of getting a disease such as
  cancer
• Different cancers have different risk factors.
  Several risk factors make a person more likely to
  develop lung cancer
• Smoking is the leading cause of lung cancer, with
  more than 90 percent of lung cancers thought to
  be a result of smoking.
• Additional risk factors include
• second-hand smoke - breathing in the smoke of
  others.
• .

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Introductory Anatomy of Urinary System

• NYUNDO Martin, MD, MMed (Surgeon)
• Lecturer
• Dpt of Surgery and Dpt of Clinical Anatomy
• FACMED-NUR

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General considerations

• The urinary system, with other organs regulates
  the volume and composition of the interstitial
  fluid.
• The urinary system consists of the following
  organs
• Two kidneys,
• a single, midline urinary bladder,
• two ureters, which carry urine from the kidneys
  to the urinary bladder
• a single urethra, which carries urine from the
  bladder to the outside of the body

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KIDNEYS

• The kidneys are the major excretory organs of the
  body they remove most waste products, many of
  which are toxic, from the blood and play a major
  role in controlling blood volume, the
  concetration of ions in the blood, the pH of the
  blood, red blood cell production and vitamin D
  metabolism.
• The skin, liver, lungs and intestines eliminate
  some waste products, but if kidneys fail to
  function, other excretory organs cannot
  adequately compensate.

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KIDNEYS

• The kidneys are bean shaped purplish-brown organs
  located below the ribs toward the middle of the
  back.
• The lie on the posterior abdominal wall behind
  the peritoneum
• The superior pole of each kidney is protected by
  the rib cage, and the right kidney is slightly
  lower than the left because of the presence of
  the liver superior to it.

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• Each kidney measures about 11cm long, 5 cm wide
  and 3cm thick and weighs about 130g
• On the medial side of each kidney is a small area
  called the hilium, where the renal artery and
  nerves enter and the renal vein and the ureter
  exit
• The hilium opens into a cavity called the renal
  sinus which contains fat and connective tissue
• The kidney is divided into an outer cortex and an
  inner medulla that surrounds the renal sinus

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• The medulla cosists of a number of cone shaped,
  renal pyramids, which appear triangular when seen
  in a longitudinal section of the kidney
• The base of each pyramid is located at the
  boundary between the cortex and the medulla, and
  the tips of the pyramids, the renal papillae are
  pointed toward the center of the kidney.

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• Funnel shaped structures called minor calyces
  surround the renal papillae
• The minor calyces from several pyramids join
  together to form larger funnels called major
  calyces
• There are 8 to 20 minor calyces and 2 or 3 major
  calyces per kidney
• This major calyces converge to form an anlarged
  channel called the renal pelvis, which is located
  in the renal sinus

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• The renal pelvis then narrows to form a small
  tube, the ureter which exits the kidney and
  connects to the urinary bladder
• Urine formed within the pyramids passes from the
  renal papillae into the minor calyces, from there
  urine moves into the the major calyces, collects
  in the renal pelvis and exits the kidney through
  the ureter.

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Nephron

• The basic histological and functional unit of the
  kidney is the nephron, which consists of an
  enlarged terminal end called Bowmans capsule, a
  proximal convuluted tubule, a loop of Henle and
  distal convuluted tubule.
• The distal convuluted tubule empties into a
  collecting duct, which carries the urine from the
  cortex of the kidney to the calyces.

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• The Bowmans capsule and both convoluted tubules
  are in the renal cortex
• The collecting tubules and parts of the loops of
  Henle enter the renal medulla.
• There are about 1.300.000 nephrons in each kidney
  and one third of them must be functional to
  ensure survival.

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BLOOD SUPPLY

• Renal artery from the abdominal aorta
• Renal vein exits the kidney and connects to the
  inferior vena cava

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Ureters and urinary bladder

• Ureters
• narrow tubes that carry urine from the kidneys to
  the bladder.
• The ureters extend inferiorly and medially from
  the renal pelvis at the renal hilium to reach the
  urinary bladder.
• Muscles in the ureter walls continually tighten
  and relax forcing urine downward, away from the
  kidneys.
• If urine backs up, or is allowed to stand still,
  a kidney infection can develop. About every 10 to
  15 seconds, small amounts of urine are emptied
  into the bladder from the ureters.

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• The urinary bladder
• is a hollow muscular container that lies in the
  pelvic cavity just posterior to the symphysis
  pubis.
• In male it is just anterior to the rectum and in
  the female it is just anterior to the vagina znd
  inferior and anterior to the uterus.
• The size of the bladder depens on the presence or
  absence of the urine.

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• The ureters enter the bladder inferiorly on its
  posterolateral surface, and the urethra exits the
  bladder inferiorly and anteriorly
• The traingular area of the bladder wall between
  the two ureters posteriorly and the urethra
  anteriorly is called trigone this region differs
  histologically from the rest of the bladder wall
  and does not expand during bladder filling

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• At the junction of the urethra with the bladder,
  smooth muscle of the bladder forms the internal
  urinary sphincter
• The external urinary sphincter is skeletal muscle
  that surrounds the the urethra as the urethra
  extends through the pelvic floor
• The sphincters control the flow of urine through
  the urethra.

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• In the male the urethra extends to the end of the
  penis, where it opens to the outside
• The female urethra is much shorter than the male
  urethra and opens into the vestibule anterior to
  the vaginal opening

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Facts about urine

• Adults pass about a quart and a half of urine
  each day, depending on the fluids and foods
  consumed.
• The volume of urine formed at night is about half
  that formed in the daytime.
• Normal urine is sterile. It contains fluids,
  salts and waste products, but it is free of
  bacteria, viruses and fungi.
• The tissues of the bladder are isolated from
  urine and toxic substances by a coating that
  discourages bacteria from attaching and growing
  on the bladder wall

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Introductory Anatomy of Reproductive System

• NYUNDO Martin, MD, MMed (Surgeon)
• Lecturer
• Dpt of Surgery and Dpt of Clinical Anatomy
• FACMED-NUR

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• Animals reproductive systems can be divided into
  the internal reproductive organs and the external
  genitalia. The gonads are the actual organs that
  produce the gametes. In the male, testes
  (singular testis) produce sperm cells, and in
  the female, ovaries make ovules (eggs).

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Male Reproductive System

• Testis
• . Sperm cells are produced in the testes located
  in the scrotum. Normal body temperature is too
  hot thus is lethal to sperm so the testes are
  outside of the abdominal cavity where the
  temperature is about 2 C (3.6 F) lower..
• Epididymis
• From there, sperm are transferred to the, coiled
  tubules also found within the scrotum, that store
  sperm and are the site of their final maturation.

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• Vas deferens (plural vasa deferentia)
• In ejaculation, sperm are forced up int the vas
  deferens From the epididymis, the vas deferens
  goes up, around the front of, over the top of,
  and behind the bladder.
• The ends of the vasa deferentia, behind and
  slightly under the bladder, are called the
  ejaculatory ducts.

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• The seminal vesicles are also located behind the
  bladder. Their secretions are about 60 of the
  total volume of the semen ( sperm and associated
  fluid) and contain mucus, amino acids, fructose
  as the main energy source for the sperm, and
  prostaglandins to stimulate female uterine
  contractions to move the semen up into the
  uterus.
• The seminal vesicles empty into the ejaculatory
  ducts. The ejaculatory ducts then empty into the
  urethra (which, in males, also empties the
  urinary bladder).

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• PROSTATE
• The initial segment of the urethra is surrounded
  by the prostate gland (note spelling!). The
  prostate is the largest of the accessory glands
  and puts its secretions directly into the
  urethra. These secretions are alkaline to buffer
  any residual urine, which tends to be acidic, and
  the acidity of the womans vagina.
• The prostate needs a lot of zinc to function
  properly, and insufficient dietary zinc (as well
  as other causes) can lead to enlargement which
  potentially can constrict the urethra to the
  point of interferring with urination.

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• The bulbourethral glands or Cowpers glands are
  the third of the accessory structures. These are
  a small pair of glands along the urethra below
  the prostate. Their fluid is secreted just before
  emission of the semen, thus it is thought that
  this fluid may serve as a lubricant for inserting
  the penis into the vagina, but because the volume
  of these secretions is very small, people are not
  totally sure of this function.

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• Penis
• The urethra goes through the penis.
• In humans, the penis contains three cylinders of
  spongy, erectile tissue (corpus cavemosum and
  corpus spongiosum) . During arousal, these become
  filled with blood from the arteries that supply
  them and the pressure seals off the veins that
  drain these areas causing an erection, which is
  necessary for insertion of the penis into the
  womans vagina.
• The head of the penis, the glans penis, is very
  sensitive to stimulation.
• In humans, as in other mammals, the glans is
  covered by the foreskin or prepuce, which may
  have been removed by circumcision.

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Female Reproductive System

• Ovary
• ovules are produced in the ovaries,
• Each ovule is released into the abdominal cavity
  near the opening of one of the oviducts or
  Fallopian tubes.

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Uterus

• The uterus is a hollow, thick-walled, pear-shaped
  muscular organ in the female reproductive system.
  
• During pregnancy the uterus expands to
  accommodate a developing embryo.
• It is located between the urinary bladder in
  front and the rectum behind, and sits above the
  vagina.
• The lower narrow portion of the uterus is called
  the cervix and it protrudes downward into the
  opening of the vaginal canal.
• The vaginal canal extends downward to the
  external female genitalia.

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• The uterine tubes, or Fallopian tubes, extend
  from either side of the uterus and act as a
  channel for eggs from the ovary to travel to the
  uterus. When an egg is fertilized (joined with
  sperm), it becomes embedded in the wall of the
  uterus (whose lining becomes thickened) where the
  fertilized egg grows into an embryo and later a
  fetus.
• If an egg is not fertilized, the thickened
  uterine lining sloughs off in a process known as
  menstruation.

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• The uterus has thick, muscular walls and is very
  small.
• In a nulliparous woman, the uterus is only about
  7 cm long by 4 to 5 cm wide, but it can expand to
  hold a 4 kg baby.
• The lining of the uterus is called the
  endometrium, and has a rich capillary supply to
  bring food to any embryo that might implant there.

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Vagina

• The vagina
• is a relatively-thin-walled chamber
• It servs as a repository for sperm (it is where
  the penis is inserted), and also serves as the
  birth canal. Note that, unlike the male, the
  female has separate opening for the urinary tract
  and reproductive system.
• These openings are covered externally by two sets
  of skin folds. The thinner, inner folds are the
  labia minora and the thicker, outer ones are the
  labia majora.
• The labia minora contain erectile tissue like
  that in the penis, thus change shape when the
  woman is sexually aroused.

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• The opening around the genital area is called the
  vestibule.
• There is a membrane called the hymen that
  partially covers the opening of the vagina. This
  is torn by the womans first sexual intercourse
  (or sometimes other causes like injury or some
  kinds of vigorous physical activity).
• In women, the openings of the vagina and urethra
  are susceptible to bacterial infections if fecal
  bacteria are wiped towards them. Thus, while
  parents who are toilet-training a toddler usually
  wipe her from back to front, thus imprinting
  that sensation as feeling right to her, it is
  important, rather, that that little girls be
  taught to wipe themselves from the front to the
  back to help prevent vaginal and bladder
  infections. Older girls and women who were taught
  the wrong way need to make a conscious effort to
  change their habits.

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• At the anterior end of the labia, under the pubic
  bone, is the clitoris, the female equivalent of
  the penis. This small structure contains erectile
  tissue and many nerve endings in a sensitive
  glans within a prepuce which totally encloses the
  glans.
• This is the most sensitive point for female
  sexual stimulation, so senstiive that vigorous,
  direct stimulation does not feel good.

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