2. Digestive System, Abdominal Cavity

Question 1

p102(hn) Lips, Oral cavity - Anatomy

Answer 1

• Palate
• Uvula
• inf. + sup. frenulum
• Tongue + mucosa
• lateral + anterior walls
  
  • lips (orbicularis oris muscle)
  • cheeks (buccinator muscle)
• inner bony wall (teeth, gum)

Question 2

Lips, Oral cavity - Borders

Answer 2

1. Vestibule
   
   • anterior: lips
   • lateral: cheeks (buccinator muscle)
   • posterior: teeh and gum
2. Oral cavity proper
   
   • superior: hard and soft palate
   • inferior: tongue + mylohyoid muscle (floor)
   • lateral: mandible + teeth

Question 3

Lips - Histology

Answer 3

• made up by orbicularis oris m.
• cutaneous + mucous surfaces:
  
  1. Cutaneous surface
     
     • outer surface
     • composed of skin
       
       • stratum corneum
       • stratum lucidum
       • straturm granulosum
       • stratum spinosum
       • stratum basale
       • (epidermis, dermis, hypodermis)
  2. Transition zone: vermillion zone
  3. Mucous membrane
     
     • inner surface
     • lines oral cavity
     • stratified squamous non-keratinized epithelium and CT
     • contains labial glands (seromucous)

Question 4

Oral cavity - Histology

Answer 4

• all lined by stratified squamous epithelium
• can be divided into 2 types:
  
  1. Masticatory epithelium
     
     • keratinised for physical strain
  2. Lining epithelium
     
     • non keratinized

Question 5

p112(hn)Salivary glands - Anatomy

Answer 5

→ large, paired glands, open into oral cavity

1. Parotid gland (+ -duct)
   
   • on side, posterior to masseter muscle
   • typical serous gland
   • duct opens into vestibule
2. Submandibular gland (+ -duct)
   
   • ​​in submandibular triangle
   • serous + mucous
   • ducts opens into sublingual papilla besides frenulum of tongue
3. Sublingual gland (+ -duct)
   
   • ​​beneath mucous membrane of the floor of mouth
   • mainly mucous
   • small gland w/ several small ducts

Question 6

Salivary glands - Blood supply

Answer 6

1. Parotid gland
   
   • ​​transverse facial artery (from external carotid)
2. Submandibular gland
   
   • glandular branches of facial artery​​
3. Sublingual gland
   
   • ​​sublingual artery

Question 7

Salivary glands - Innervation

Answer 7

1. Parotid gland
   
   • Otic ganglion (9 - Glossopharyngeal nerve)
2. Submandibular gland
   
   • Submandibular ganglion (7 - Facial nerve - chorda tympani)
3. Sublingual gland
   
   • Submandibular ganglion (7 - Facial nerve - chorda tympani)

Question 8

Salivary glands - Histology

Answer 8

• Secretory portion + ducts
  
  1. Serous acini
     
     • round nuclei
     • basal part: ribosome- + rough ER- rich
       
       • enyzme secretion!
     • narrow lumen
  2. Mucous acini
     
     • contain mucin granules
     • wide lumen
  3. Mixed acini
     
     • serous + mucous cells mix
     • form Gianuzzi’s demilune

Question 9

p36(hn) Teeth - Anatomy

Answer 9

• surrounded by gingiva
• held in alveolar socket by periodontal lig.
• consist of:
  
  • Enamel
    
    • very hard, covers crown
  • Dentin
    
    • hard, nutured by dental pulp through fine dental tubules
  • Pulp
    
    • blood vessels, nerves, lymphatics
    • opens at apex of root

Question 10

Teeth - Parts, Dentition

Answer 10

• Parts of the tooth:

1. Crown
2. Neck
3. Root
   
   • ​​​Maxillary molars: 3 roots
   • Mandibular molars: 2 roots
4. ​Pulp cavity
5. Root canals

• Dentition in adults (teeth in each quadrant):
  
  1. ​​Incisors - 2 - biting/cutting
  2. Canines - 1 - tearing
  3. Premolar - 2 - grinding
  4. Molars - 3 - grinding

Question 11

Teeth - Blood supply

Answer 11

→ all teeth are supplied directly or by branches of the maxillary artery:

1. Inferior alveolar art.
   
   • through mandibular foramen
2. Anterior superior alveolar art.
   
   • incisors + canine
3. Posterior superior alveolar art.
   
   • premolars + molars

Question 12

Teeth - Innervation

Answer 12

→ from V. - trigeminal nerve:

1. Maxillary teeth
   
   • ​​alveolar branches of Maxillary nerve (V₂)
2. Mandibular teeth
   
   • ​​inferior alveolar branch of Mandibular nerve (V₃)

Question 13

Teeth - Histology

Answer 13

• 4 major layers of the tooth:

1. Dentin
   
   • 80% hydroxyl apatite crystals (hard)
   • 20% collagen type 1 + proteogrycans
   • produced by odontoblasts within pulp, which extend throughout dentin in dental tubules
2. Enamel
   
   • 98% hydroxyl apatite crystals
   • 2% insoluble proteins
   • no cells!
3. Cementum
   
   • ​​50% hydroxyl apatite crystals
   • 50% mainly collagen fibers
   • covers root
   • produced by cementoblasts
   • connected to alveolar bone by sharpey’s fibres
4. Pulp
   
   • ​​loose CT
   • rich in capillaries + nerves
   • cells are:
     
     • fibroblasts
     • mast cells
     • macrophages
     • lymphocytes
     • odontoblasts

Question 14

p104(hn)Tongue - Anatomy

Answer 14

• skeletal muscle covered w/ mucous membrane
• attached by muscles to
  
  • hyoid bone
  • mandible
  • styloid process
  • palate
  • pharynx
• sulcus terminalis divides it into 2 parts
  
  • anterior 2/3 and posterior 1/3

Question 15

Tongue - Surface

Answer 15

• strong stratified squamous epithelium forms lingual papillae:
  
  • ​​have mechanical funtion
  • contain taste buds

1. Filiform papillae
   
   • ​​cone shaped
2. Fungiform papillae
   
   • ​​mushroom shaped, along margins
3. Vallate papillae
   
   • ​​invaginations, along V-shape terminal sulcus
4. Foliate papillae​​​
   
   • at the side of the tongue​​

Question 16

Tongue - Muscles

Answer 16

• tongue is divided into left and right half by median CT septum → all muscles are paired

1. Intrinsic muscles - Hypoglossal nerve
   
   • originate and insert within the tongue
   1. Superior longitudinal m.
   2. Inferior longitudinal m.
   3. Transverse m.
   4. Vertical m.
2. Extrinsic muscles - Hypoglossal nerve
   
   • ​​originate outside and insert into the tongue
   1. Genioglossus m.
   2. Hyoglossus m.
   3. Styloglossus m.
   4. Palatoglossus m. (Vagus nerve!)

Question 17

Tongue - Blood supply

Answer 17

Arteries

• lingual art. (from the external carotid art.)

Veins

• dorsal lingual and deep ingual vein

Question 18

Tongue - Innervation

Answer 18

1. Sensory innervation
   
   • ​​Glossopharyngeal n. (IX.)
   • Lingual n. (br. of mandibular nerve (V₃.)
   • Facial n. (VII.)
2. Motor innervation
   
   • ​​Hypoglosseal n. (XII.)

Question 19

Tongue - Histology

Answer 19

• non-keratnized squamous epithelium
• contains glands, papillae, taste buds

1. Glands
   
   1. von Ebner’s glands
      
      • serous
      • anterior to sulcus terminalis
      • open at vallate and foliate papillae
   2. posterior lingual glands
      
      • mucous
      • in root of tongue
   3. anterior lingual glands
      
      • ​​mixed
      • in apex of tongue
2. Papillae
   
   1. Filiform papillae
      
      • conical, highly keratinized
      • no taste buds
   2. Fungiform papillae
      
      • mushroom-like
   3. Foliate papillae
      
      • ​​longitudinal folds on lateral borders of tongue
   4. ​​Circumvallate papillae
      
      • ​​​circular papillae anterior to terminal sulcus
      • Von Ebner’s glands empty here

Question 20

Palate - Anatomy

p28(hn) hard

p102 soft

Answer 20

→ forms roof of mouth and floor of nasal cavity.

can be devided into:

1. Hard palate
   
   • ​​anterior 90% of palate
   • palatine processes of maxilla + horizontal plates of palatine bones
   • anterior medially: incisive foramen
   • posterior laterally: greater + lesser palatine foramina
   • intermaxillary suture, interpalatine suture
2. Soft palate
   
   • ​​fibromuscular fold, moves against pharyngeal wall to close faucial isthmus when swallowing or speaking
   • posteriorly: uvula

Question 21

Palate - Muscles

Answer 21

→ Innervated by vagus nerve

1. Tensor veli palatini m. (Mandibular (V3) n.)
2. Levator veli palatini m.
3. Palatoglossus m.
4. Palatopharyngeus m.
5. Uvular m.

Question 22

Palate - Histology

Answer 22

• covered by a thick stratified squamous epithelium
• supported by densely collagenous lamina propria
• bound down by relatively dense submucosal tissue
  
  • contains a few accessory salivary glands

Question 23

p32(i)Anatomy of the Pharynx

Answer 23

• Funnel-shaped, fibromuscular tube
• Extends from base of skull → inferior border of cricoid cartilage

Question 24

Topography of the Pharnyx

Answer 24

1. Nasopharynx
   
   • Connected to Eustachian tube(equalizes air pressure on both sides of tympanic membrane) through the tympanic cavity
   • Communicates with nasal cavities through choanae
   • pharyngeal tonsils in posterior wall
2. Oropharynx
   
   • Extends between soft palate and the epiglottis
   • Communicates with mouth through oropharyngeal isthmus
   • Contains palatine tonsils
3. Laryngopharynx
   
   • Extends from upper border of epiglottis to lower border of cricoid cartilage
   • Contains piriform recesses on each side of opening of larynx→swallowed objects might get stuck here

Question 25

Circular muscles of the Pharynx

Answer 25

• Superior constrictors - constricts upper pharynx
• Middle constrictors - constricts lower pharynx
• Inferior constrictors - constricts lower pharynx (also innervated by reccurent and external laryngeal nerves)

Question 26

Longitudinal muscles of the Pharynx

Innervation : Vagus nerve

Answer 26

• Stylopharyngeus - elevates pharynx and larynx (innervated by glossopharyngeal nerve)
• Palatopharyngeus - elevates pharynx and larynx, closes nasopharynx
• Salpingopharyngeus- elevates pharynx, opens auditory tube

Question 27

Blood supply of the Pharynx

Answer 27

Ascending:

• pharyngeal artery (smallest branch of external carotid artery)
• palatine branch of the facial artery

Descending:

• palatine arteries(branch of internal maxillary artery)
• Pharyngeal branches of maxillary artery
• branches of sup. + inf. thyroid arteries

Question 28

Innervation of Pharynx

Answer 28

Pharyngeal plexus :

• Lies on middle pharyngeal constrictor m.
• Formed by pharyngeal branches of glossopharyngeal and vagus nerves
• Vagal branch innervates all muscles of pharynx except stylopharyngeus : glossopharyngeal n.
• Glossopharyngeal portion supplies sensory fibres to the pharyngeal mucosa

Question 29

Tonsils - Anatomy

Answer 29

• Pharyngeal tonsil
  
  • found in the posterior wall and roof of the nasopharynx
  • called an adenoid when enlarged
• Palatine tonsil
  
  • on each side of the oropharynx
  • between the palatoglossal and palatopharyngeal folds
• Tubal tonsil
  
  • lymphoid nodules near the pharyngeal opening of the auditory tube
• Lingual tonsil
  • lymphoid follicles on the posterior portion of the dorsum of the tongue

Question 30

Tonsils - Histology

Answer 30

• non-encapsuled masses of lymphoid tissue
• covered with a stratified squamous epithelium
• epithelial cells are able to phagocytose bacteria, and transfer them to macrophages

Question 31

Abdominal regions

Answer 31

• 9 different regions
• each region includes an underlying organ

Question 32

p72(i)Esophagus - Anatomy

Answer 32

• 25 cm long, continuation of the pharynx
• behind trachea and larynx
• from carina: runs in posterior mediastinum
• 2 muscle layers: peristaltic movement
  
  • internal circular m.
  • external longitudinal m.
• through esophageal hiatus in diaphragm
• empties in cardial orifice of stomach, left of the midline at T11 vertebra

Question 33

Esophagus - Blood supply

Answer 33

Arteries:

• left gastric artery (from celiac trunk)
• left inferior phrenic artery

Veins:

• left gastric vein (to portal vein, to liver)
• esophageal vein (to azygous vein)

Question 34

Esophagus - Innervation

Answer 34

→ happens through esophageal nerve plexus

formed by

• vagal trunks
• thoracic sympathetic trunks
• periarterial plexuses around the arteries of the E.
• right and left vagus nerves

Question 35

Esophagus - Histology

Answer 35

→ 4 Layers, from in- to outside

1. Tunica mucosa
   
   1. Epithelial lamina
      
      • non-keratinized stratified squamous epithelium
   2. Proper mucous lamina
      
      • cardiac esophageal glands
        
        • produce mucin
      • lymphatic elements
   3. Muscular mucous lamina
      
      • ​​longitudinal smooth muscle
2. Tunica submucosa
   
   • ​longitudinal folds, small salivary glands
3. Tunica muscularis
   
   • _​​_striated, mixed, smooth muscle
4. Tunica adventitia
   
   • _​​_outermost layer

Question 36

p184(i)Stomach - Anatomy

Answer 36

→ intraperitoneal organ located in epigastric and left hypochondriac regions

1. Cardia
   
   • surrounds cardiac orifice at T10 level
2. Fundus
   
   • inferior to the apex of the heart at level of 5th rib
   • may contain air bubble on x-ray
3. Corpus (Body)
   
   • has lesser and greater curvatures
4. Pylorus​​
   
   • P. antrum → P. canal → P. sphincter
   • at L1 level

Question 37

Stomach - Peritoneal relations

Answer 37

→ intraperitoneal

1. hepato•gastric lig. (part of les. omentum)
   
   • inferior margin of liver ⇔ lesser curvature
   • carries right and left gastric art.
2. gastro•colic lig. (part of gr. omentum)
   
   • ​​greater curvature ⇔ transverse colon
   • forms anterior part of lesser sac
3. gastro•splenic lig. (part of gr. omentum)
   
   • ​greater curvature ⇔ hilum of spleen
4. gastro•phrenic lig.
   
   • fundus of stomach ⇔ left crus of diaphragm

Question 38

Stomach - Blood supply

Answer 38

Arteries

• Lesser curvature
  
  • sup.: left gastric art. (from celiac trunk)
  • inf.: right gastric art. (from common hepatic art.)
• Greater curvature
  
  • ​sup.: left gastro-omental art. (from splenic art.)
  • inf.: right gastro-omental art. (from gastroduodenal art.
• Fundus
  
  • short gastric artery (from splenic art.)

Veins

• Lesser curvature
  
  • sup.: left gastric vein (to portal vein)
  • inf.: right gastric vein (to portal vein)
• Greater curvature
  
  • ​sup.: left gastro-omental vein (to splenic vein)
  • inf.: right gastro-omental vein (to sup. mesenteric vein)
• Fundus
  
  • short gastric vein (to splenic vein)

Question 39

Stomach - Innervation

Answer 39

Parasympathetic:

• ​post. + ant. vagal trunk

Sympathetic:

• major + minor splanchnic nerve
• coeliac ganglion

Question 40

Stomach - Histology

Answer 40

3 histological parts:

• cardia (esophageal-cardial junction)
  
  • change: non-keratinized stratified squamous → simple columnar epithelium
• fundus + body
• pylorus (pyloric-duodenal junction)
  
  • Brunner’s gland

5 Layers:

1. Tunica mucosa
   
   1. Lamina epithelium
      
      • simple columnar epithelium
      • forms gastric pits
      • produce mucin for HCl protection
   2. Lamina propria
      
      • loose CT, many lymphocytes
      • hosts gastric glands
   3. Lamina muscularis mucosae
      
      • circular- + longitudinal muscle fibers
2. Tunica submucosa
   
   • loose CT
   • blood vessels, lymphocytes, mast cells, macrophages, adipocytes
3. Tunica muscularis
   
   • ​​3 layers: inner, middle, outer sublayer
4. Tunica subserosa
5. Tunica serosa
   
   • ​​loose CT
   • mesothelium

Gastric glands:

1. Cardiac glands
   
   • gastric pits
2. Fundid glands
   
   • smaller gastric pits
   • Chief cells: pepsinogen
   • parietal cells: HCl
3. Pyloric glands​
   
   • ​​produce mucous

Question 41

p188(i)Duodenum - Anatomy

Answer 41

• C-shape around head of pancreas
• arises from Fore- + Midgut

4 Parts

1. superior part
   
   • intraperitoneal
   • hepato•duodenal lig. (part of the lesser omentum)
2. descending part
   
   • 2^nd retroperitoneal
   • descends on right side of L1-L3
   • major duodenal papilla (p. of Vater)
     
     • entrance of bile duct!
3. horizontal part​​
   
   • 2^nd retroperitoneal
   • crosses L3 vertebra
   • ventral: sup. mesenteric art. + vein
   • dorsal: aorta + IVC
4. ascending part
   
   • ​​duodeno•jejunal junction (L2 ver.)

Question 42

Duodenum - Blood supply

Answer 42

Arteries

1. Foregut part (ampulla → major duodenal papilla)
   
   • sup. pancreatico•duodenal art.
     
     • from gastro•duodenal art. of celiac trunk
2. Midgut part (papilla → )
   
   • inf. pancreatico•duodenal art.
     
     • from superior mesenteric artery

Veins

• Duodenal vein (to portal vein)

Question 43

p190(i)Jejunum and Ileum - Anatomy

Answer 43

Jejunum

• makes up 40% of small intestine
• from duodeno•jejunal flexure
• circular folds
• Peyer’s patches: lymphoid tissue
• larger in diam., thicker walls than ileum
• less arterial arcades (anastomotic loops), longer straight art. in its mesentary than ileum

Ileum

• makes up 60% of small intestine
• ends at ileo•coecal junction
• occupies false pelvis
• shorter circular folds than jejunum

Question 44

Jejunum and Ileum - Peritoneal relations

Answer 44

• intraperitoneal
• mesenterium proprium

Question 45

Jejunum and Ileum - Blood supply

Answer 45

Arteries

• all midgut!
  
  • ​sup. mesenteric art.
    
    • ​jejunal art.
    • ileal art.
  • make arcades that run within the mesentery
    
    • ​vasa recta/straigt art. extend from it

Veins

• ​superior mesenteric vein (to splenic vein)

Question 46

Duodenum, Jejunum, Ileum - Innervation

Answer 46

Parasympathetic:

• vagus nerve

Sympathetic:

Duodenum:

• celiac ganglion

Jejunum, Ileum:

• superior mesenteric ganglion

Question 47

Small intestine - Histology

Answer 47

Folds/projections (rich in capillaries)

• Circular folds (Kerkring’s valve)
  
  • 1 cm long circular folds in tunica muscularis
• Intestinal villi
  
  • 1 mm long finger like projections of mucous membrane into the lumen
    
    • increases internal surface

5 Layers:

1. Tunica mucosa
   
   • intestinal villi
   • epithelium with
     
     • enterocytes (absorbtive cells)
     • goblet cells
     • lymphocytes
   1. Epithelial lamina
      
      • simple columnar epithelium
   2. Proper lamina
      
      • smooth muscles
      • capillaries
      • glands
   3. Muscular mucous lamina
      
      • duodenum: discontinous
      • jejenum: continous
        
        • crypt’s of Lieberkühn
      • ileum: discontinous (lymphatic follicles “Peyer’s patches)
2. Tunica submucosa
   
   • _​​_loose CT
   • submucosal plexus
3. Tunica muscularis
   
   • _​​_longitudinal + circular
   • Auerbach plexus
4. Tunica serosa
   
   • loose CT
   • mesothelium

Question 48

p192(i)Large intestine - Anatomy

Answer 48

→ extends from ileo•cecal junction to anus (1.5 m long)

consists of 4 parts:

1. Coecum
   
   • receives bolus from ileum
   • surrounded by peritoneum, NO mesentary
2. Appendix
   
   • ​​narrow, hollow, muscular tube with aggregations of lymphoid tissue
   • has meseoappendix
3. Colon, ​​has 4 parts:
   
   1. Ascending colon (retroperitoneal)
   2. Transverse colon (intraperitoneal, transverse mesocolon )
   3. Descending colon (retroperitoneal)
   4. Sigmoid colon (intraperitoneal, sigmoid mesocolon)
4. Rectum and anal canal

Question 49

Large intestine - Peritoneal relations

Answer 49

1. Caecum
   
   • ​​intraperitoneal (sometimes extraperitoneal)
   • meso•caecum
2. Appendix
   
   • ​​intraperitoneal
   • meso•appendix
3. Colon
   
   1. ​​​Ascending colon
      
      • ​​2^nd retroperitoneal
   2. Transervse colon
      
      • ​​intraperitoneal
      • phreni•colic lig.
      • phreni•splenic lig.
      • gastro•colic lig.
   3. Descending colon
      
      • ​​2^nd retroperitoneal
   4. Sigmoid colon
      
      • intraperitoneal
      • meso•sigmoideum
4. Rectum
   
   1. ​​upper 1/3
      
      • ​​intraperitoneal
      • meso•rectum
   2. middle 2/3
      
      • ​​2^nd retroperitoneal
   3. lower 3/3
      
      • ​​infraperitoneal

Question 50

Large intestine - Blood supply

Answer 50

Arteries

1. Caecum
   
   • caecal aa. (from ileo•colic art., from sup. mesenteric artery)
2. Appendix
   
   • appendicular art. (from ileo•colic art., from sup. mesenteric artery)
3. Colon, ​​has 4 parts:
   
   1. Ascending colon
      
      • ​right colic art. (from sup. mesenteric artery)
   2. Transverse colon
      
      • middle colic art. (from sup. mesenteric artery)
   3. Descending colon
      
      • ​left colic art. (from inf. mesenteric artery)
   4. Sigmoid colon​
      
      • ​​sigmoid aa.
4. ​Rectum and anal canal
   
   1. ​upper 1/3
      
      • ​​sup. rectal art. (from inf. mesenteric artery)
   2. middle 1/3
      
      • middle rectal art. (from internal iliac artery)
   3. lower 1/3​
      
      • ​​inferior rectal art. (from internal pudendal artery

Veins

→ veins have the same names!

Question 51

Large intestine - Innervation

Answer 51

Parasympathetic

1. Vagus nerve
   
   • until left colic flexure
2. Pelvic splanchnic nerves
   
   • left colic flexure until anus

Sympathetic

1. Sacral splanchnic nerves

Question 52

Large intestine - inner surface

Answer 52

• semilunar folds on the inside caused by
  
  • free taenia
  • omental taenia
  • meso•colic taenia
• outside: omental appendices
  
  • fat-filled bulges of peritoneum

Question 53

Large intestine - Histology

Answer 53

1. Tunica mucosa
   
   • _​​_intestinal glands: goblet & absorptive cells
   • Lamina epithelialis: simple columnar
   • Lamina propria: loose CT, rich in lymphoid nodules
   • Lamina muscularis: smooth muscle
2. Tunica submucosa
   
   • Loose CT, Meissner’s plexus
3. Tunica muscularis
   
   • teniae coli : outer longitudinal muscle fibres
   • haustra coli: small pouches caused by sacculation
4. Tunica adventitia-serosa:
   
   • tunica serosa: mesothelium
   • tunica adventitia: not covered by peritoneum; loose CT

Question 54

p216 (i)Pancreas - Anatomy

Answer 54

→ 2^nd retroperitoneal organ, lying in lesser sac, consisting of 3 parts:

1. head (L1-L2 level)
   
   • lies in C-shape of duodenum
   • ​​pancreatic duct → major duodenal papilla
   • accessory panc. duct → minor duodenal papilla
2. body​​​​
   
   • ​​has omental eminence
3. tail

Question 55

Pancreas - Blood supply

Answer 55

Arteries

1. Head
   
   • ​​sup. + inf. pancreatico•duodenal art. (from gastroduodenal art., from common hepatic art.)
2. Body
   
   • ​​splenic art.

Veins

• Splenic vein (to hepatic portal vein)

Question 56

Pancreas - Innervation

Answer 56

• Celiac ganglion
• Vagus nerve

Question 57

Pancreas - Histology

Answer 57

1. Exocrine part
   
   • compound alveolar acinar glands
   • centroacinar cells
   • intercalated ducts
   • purely serous
2. Endocrine part
   
   • ​​islets of Langerhans
     
     • alpha - secrete glucagon
     • beta - secrete insulin

Question 58

p206(i)Liver - Anatomy

Answer 58

• largest visceral organ, largest gland in body
• bare area (not peritoneal!)
  
  • not enclosed by coronary lig.

4 main parts:

1. right lobe​​
   
   • ​​between: Falciform- + round lig.
2. left lobe
3. quadrate lobe
   
   • ​​inferiorly on posterior side
   • receives blood from the left hepatic art.
   • drains bile into the left hepatic duct
4. caudate lobe
   
   • ​​superiorly on posterior side
   • receives blood from right + left hepatic art.
   • drains bile into right + left hepatic duct

Question 59

Liver - Peritoneal relations

Answer 59

peritoneal ligaments:

1. falciform lig.
2. coronary lig.
3. right triangular lig. → hepato•renal lig.
4. left triangular lig. → fibrous appendix of liver hepato•duodenal lig.

Porta Hepatis: attachment point for lesser omentum!

Question 60

Liver - Topography

Answer 60

Superior - diaphragmatic surface

Anterior

• right lobe
  
  • divided by falciform lig.
• left lobe

Posterior - visceral surface

• H-shaped fissures for:
  
  1. ​Porta hepatis
     
     • common hepatic duct
     • hepatic portal vein
     • hepatic art.
  2. venous lig.
  3. round lig.
  4. IVC
  5. gallbladder

Question 61

Liver - Blood supply

Answer 61

Arteries

1. Oxigenated blood
   
   • proper hepatic artery (25%) (from common hepatic art.)
2. Deoxigenated blood
   
   • hepatic portal vein (75%) (to IVC)

→ both vessels branch further in liver:

• interlobar a. + v.→
• interlobular a. + v.→
• perilobular a. + v.→
• liver sinusoid (capillaries) →
• central veins →
• sublobular veins →
• hepatic veins →
• IVC

Question 62

Liver - Histology

Answer 62

• dual blood supply (hepatic art. + hepatic portal v.)
• sheets of connective tissue divide liver into thousands of lobules
  
  • lobule has hexagonal in shape, with portal triads and a central vein:
    • branch of portal vein
    • branch of hepatic artery
    • branch of bile duct
• hepatic acinus is oriented around the afferent vascular system.
• hepatocytes: polygonal cells, joined to one another in anastomosing plates
  
  • have abundant rough and smooth endoplasmic reticulum, and Golgi membranes
  • make contact with blood in sinusoids
    
    • vascular channels lined with highly fenestrated endothelial cells
  • Space of Disse:
    
    • space between sinusoids & hepatocytes
    • contains Kuppfer cells : macrophages
• Bile: secretions from the basal surface of hepatocytes
  
  • collect in channels called canaliculi and flow hepatic bile duct

Question 63

Liver - Function

Answer 63

• many different functions!
• production + secretion of bile
• detoxification
• storage of glycogen
• protein synthesis
• production of heparin + bile pigments

Question 64

p218(i)Spleen - Anatomy

Answer 64

• large, vascular, lymphatic organ
• ​medulla
  
  • white pulp
    
    • lymphatic tissue
  • red pulp
    
    • venous sinusoids
    • hematopoietic in early life
    • later destroys old RBC

Question 65

Spleen - Blood supply

Answer 65

Arteries

• splenic art. (from celiac art.)

Vein

• splenic vein (to hepatic portal vein)

Question 66

Spleen - Peritoneal relations

Answer 66

• intraperitoneal
• supported by
  
  • spleno•gastric lig.
  • spleno•renal lig.

Question 67

Spleen - Topography

Answer 67

• Costal surface
  
  • impressions of ribs
• Visceral surface​​
  
  • hilum
  • gastric impression
  • renal impression
  • colic impression
  • pancreatic impression
• Superior border
• Inferior border

Question 68

Spleen - Histology

Answer 68

• capsule: dense CT

1. White pulp (lymphoid part)
   
   1. lymphoid follicles
      
      • B-lymphocytes
   2. Periarterial lymphatic sheet
      
      • T-lymphocytes
   3. Marginal zone
      
      • macrophages (splenocytes)
2. Red pulp (haemopoietic part of spleen)
   
   1. ​Sinusoid
      
      • intercellular spaces for blood passage
      • only healthy RBCs can enter (due to flexibility)
   2. Splenic cords
      
      • reticular cells + fibres, macrophages, plasma cells
      • phagocytes old RBCs

Question 69

p210-212(i) Extrahepatic bile system - Anatomy

Answer 69

1. Gallbladder
   
   • on visceral surface of liver, covered by peritoneum
   • consists of 4 parts:
     
     • ​fundus
     • body
     • neck
     • cystic duct
   1. receives + stores bile from liver
   2. concentrates it (collecting salt and water)​​​​
2. Liver
   
   • ​​right + left hepatic duct
3. Pancreas​
   
   • pancreatic duct

​⇒ They come together and all drain into the major duodenal papilla (p. of Vater)

Question 70

Extrahepatic bile system - Blood supply

Answer 70

Arteries

• Cystic art. (from hepatic art. proper)

Veins

• Cystic vein (to hepatic portal vein)

Question 71

Extrahepatic bile system - Histology

Answer 71

• mucosa is thrown into many folds
• lumen is lined with a high columnar epithelium
• connective tissue wall contains abundant elastic fibers and layers of smooth muscle
• epithelium rests on a highly vascularized lamina propria
  • epithelial cells are devoted to absorption of inorganic salts and water
  • provide the mechanism for the gallbladder’s ability to concentrate bile

Question 72

p154(i)Peritoneum - Anatomy

Answer 72

→ greatest serous membrane system of body, lined with mesothelial cells

consists of 2 layers:

• Parietal peritoneum​
• Visceral peritoneum

Divides abdominal cavity into:

• Preperitoneal space
• Peritoneal cavity
  
  • females: opened via genital tract
  • males: completely closed!
• Retroperitoneal space
• Infraperitoneal space (→ lesser pelvis)

Question 73

Peritoneum - Functions

Answer 73

• covers and fixes the viscera (=organs)
• protects viscera and its supplying vessels
• produces peritoneal fluid
• resorps (peritoneal dialysis)

Question 74

Peritoneum - Blood supply

Question 75

Peritoneum - Organ classification

Answer 75

1. Intraperitoneal
   
   • organs lying in duplicature of visceral peritoneum called mesentary
2. Retroperitoneal
   
   1. ​primary
      
      • ​​retroperitoneal from the beginning of embryonal development
   2. secondary
      
      • becomes retroperitoneal at one stage of development
3. Infra-/Extraperitoneal
   
   • organs caudally to the peritoneum
4. Praeperitoneal
   
   • organs ventrally to the peritoneum

Question 76

Peritoneum - Recesses

Answer 76

The peritoneal cavity can be divided into:

1. Lesser sac (omental bursa)
   
   • only opening: Epiploic foramen
     
     • ​posterior to hepato•duodenal foramen
   • has 3 recesses
     
     • superior
     • inferior
     • splenic (at hilus of spleen)
2. Greater sac
   
   1. subprenic recess
   2. hepato•renal recess
   3. paracolic recess
   4. Douglas pouch (posterior to uterus)
   5. vesicouterine pouch (anterior to uterus)

Question 77

Peritoneum - Innervation

Answer 77

Parietal peritoneum

• somatic nerves

Visceral peritoneum

• visceral nerves

Question 78

Peritoneum - Histology

Answer 78

• thin layer of loose connective tissue covered by a single layer of mesothelial cells
• mesothelial cells:
  
  • simple squamous cells
  • microvilli on surface and are very fragile
• fibroelastic tissue is present within the connective tissue layer to provide support

Question 79

p156(i)Greater and lesser omentum - Anatomy

Answer 79

​Lesser omentum

• porta hepatis ⇔ lesser curvature of stomach and beginning of duodenum
• consists of:
  
  • hepato•gastric lig.
  • hepato•duodenal lig.
• forms anterior wall of lesser sac
• contents:
  
  • common bile duct
  • portal vein
  • hepatic art. proper

​​​​​​Greater omentum

• greater curvature of stomach ⇔ transverse colon
• hangs down into peritoneal cavity
• holds right + left gastroepiploic vessels
• Consists of:
  
  • Gastro•splenic lig.
  • Spleno•renal lig.
  • Gastro•phrenic lig.
  • Gastro•colic lig.

Question 80

Tributaries of the IVC

Answer 80

→ forms from union of right + left common iliac veins

• Lumbar veins
• Gonodal vein
  
  • testicular vein
  • ovarian vein
• Renal vein
• Suprarenal
• Hepatic vein
• inferior phrenic vein

Question 81

Abdominal aorta - Paired vs. unpaired branches

Answer 81

1. Visceral
   
   1. paired
      
      • _​​_middle suprarenal art.
      • renal art.
      • gonadal art.
   2. unpaired
      
      1. _​_sup. + inf. mesenteric art
      2. celiac trunk
2. Parietal
   
   1. paired
      
      • _​​_inf. phrenic art.
      • lumbar art. (4 pairs)
   2. unpaired
      
      • _​​_median sacral art.

Question 82

Portal vein - Tributaries

Answer 82

→ from gastrointestinal organs + spleen to liver

1. sup. + inf. mesenteric veins
2. splenic vein
3. right + left gastric veins
4. cystic vein
5. sup. pancreatico•duodenal vein
6. paraumbilical vein

Question 83

Portocaval Anastomoses

Answer 83

→ allow communication between portal- and systemic venous system

→ provides collateral circulation during portal obstruction

1. Esophageal anastomosis
   
   • left gastric vein ⇔ azygous vein
2. Rectal anastomosis (haemorrhoids!)
   
   • between superior, middle, inferior rectal veins
3. Paraumbilical anastomosis (portal hypertension)
   
   • paraumbilical vein ⇔ sup. + inf. epigastric vein
4. Retroperitoneal anastomosis
   
   • ​​colic veins ⇔ abdominal wall veins

Question 84

Sympathetic trunk in abdomen

Answer 84

• ganglia of AST found in lateral horns of T5-T12 vertebra
• in the abdomen the nerves that arise from the spinal segments will pass through the sympathetic trunk without synapsing→ splanchnic nerves

1. Paravertebral ganglia
   
   • have inter-ganglionic connections→ sympathetic trunk
     
     • named according to location
2. Pre-vertebral ganglia :
   
   • located at origins of the major branches of abdominal aorta
   • named after arteries

Question 85

Parasympathetic Innervation

Answer 85

Consists of 2 parts

1. Cranial
   
   • presynaptic ganglion: dorsal nucleus of vagus nerve
   • postsynaptic ganglion: visceral ganglia
2. Sacral
   
   • Presynaptic: lateral horns of S2-S4 spinal cord segments
   • Form pelvic splanchnic nerves → inferior hypogastric plexus

Question 86

Autonomic Ganglia and Plexuses

Answer 86

formed by sym and parasym nerve fibers

Plexi

1. Celiac plexus
   
   • hepatic plexus: liver, gall bladder
   • gastric plexus: stomach
   • splenic plexus: spleen
   • pancreatic plexus: pancreas, duodenum
2. Superior mesenteric plexus(w/ its ganglia)
   
   • head of pancreas
   • small intestine
   • colon
   • ovary
3. Suprarenal,Renal plexus(w/ corticorenal ganglion)
   
   • Ureteral plexus: kidney, proximal ureter
4. Ovarian/Testicular plexus
   
   • direct innervation : ovary and testis
   • superior hypogastric plexus : ureter, genital organs
5. Inferior hypogastric ganglia(w/ pelvic ganglia)
   
   • middle inferior rectal plexus
   • prostatic plexus
   • deferential plexus
   • uterovaginal plexus
   • vesical plexus

Question 87

Anatomy of the abdominal segment of the Vagus nerve

Answer 87

• After it becomes anterior and posterior trunks around the esophagus
  
  • anterior trunk terminates at esophagus
  • posterior trunk goes on to supply→ small & large intestine until distal part of transverse colon

Question 88

Anatomy & fine structure of GI nerves

Answer 88

1. Liver, gallbladder, stomach
   
   • sym: celiac ganglion
   • parasym: vagal trunk
2. Pancreas, duodenum, spleen
   
   • sym: celiac + superior mesenteric ganglia
   • parasym: posterior vagal trunk
3. Jejenum, ileum, cecum, as. + trans. colon(prox 2/3)
   
   • sym: superior mesenteric ganglion
   • parasym : vagal trunk
4. Trans. colon(dist. 1/3), desc.+sigmoid colon, upper rectum
   
   • sym: inferior mesenteric ganglion
   • parasym: pelvic splanchnic nerves
5. Mid+Lower rectum
   
   • sym: lumbar+ sacral splanchnic nerves
   • parasym: pelvic splanchnic nerves

Question 89

Enteric plexus, head zones

Answer 89

• located in intramucosal system
• both parasympathetic and sympathetic
• 3 subtypes
  
  1. Submucosal plex : Meissner plexus
  2. Myenteric plexus: Auerbach plexus
  3. Subserosal plexus
• Headzones:
  
  • areas where pain appears to occur although it originates from another visceral area
  • “referred pain”
  • E.g : diaphragm pain may seem to originate from cutaneous areas
  • gall bladder inflammation

Question 90

Enteroendocrine cells in GI

Answer 90

• found in epithelium and wall of glands
• endocrine- and paracrine secretion
• G, K, L, I, N, S- Cells

1. Stomach
   
   • G-Cells
     
     • gastrin secretion
2. Intestine
   
   • K-Cells
     
     • gastric inhibitory peptide
     • promotes triglyceride storage
   • L-Cells
     
     • ileum + colon
     • secrete glucagon-like peptide (1 + 2)
     • surpresses glucagon
   • I-Cells
     
     • jujenum + duodenum
     • CKK secretion
     • manages bile secretion
   • N-Cell
     
     • jujenum
     • neurotensin
     • controls smooth muscle
   • S-Cell
     
     • duodenum + jujenum
     • secretin
     • stimulates secretion of pancreas

Question 91

Immune cells in GI

Answer 91

• located in mucosa + submucosa of gut

1. Tonsils/Vermiform appendix
   
   • lymphoid follicles
2. MALT-Cells
   
   • M-Cells
     
     • transport antigens to cells in lamina propria
3. Lymphoid follicles
   
   • in submucosa extending into lamina propria

Question 92

Portocaval Anastomoses

Answer 92

• Esophageal:
  
  • Condition: Esophageal varicis
  • Portal: Esophageal branch→ left gastric vein
  • Systemic: esophageal branch→azygous
• Rectal:
  
  • Condition: Rectal varicis
  • Portal: Superior rectal vein
  • Systemic: middle & inferior rectal veins
• Paraumbilical:
  
  • Condition: Caput medusae
  • Portal: Paraumbilical veins
  • Systemic: Superficial epigastric vein
• Retroperitoneal:
  
  • Portal: Right,middle,left colic veins
  • Systemic: Renal, suprarenal, paravertabral & gonadal veins

Question 93

p155(i)Abdominal Wall - Inner surface

Answer 93

From midline → lateral on both sides:

• median umbilical lig., w/ urachus (remnant)
  
  • supravesical fossa
• medial umbilical lig., w/ umbilical art. (remnant)
  
  • medial fossa
• lateral umbilical fold, w/ inf. epigastric art.
  
  • lateral fossa

covered by parietal peritoneum!

Question 94

Rectus sheet - Cross section

Answer 94

• above + below arcuate line
• arcuate line
  
  • inferior epigastric vessels perforate the rectus abdominis m.

Question 95

Posterior Abdominal Wall - Muscles

Answer 95

1. Psoas major m.
   
   • from T12 and L1 vertebrae to lesser trochanter
2. Psoas minor m.
   
   • from T12 and L1 vertebrae to iliopubic eminence
3. Quadratus lumborum m.
   
   • from iliac crest + LV transverse processes towards 12th tib
4. Iliacus m.
   
   • from iliac crest towards lesser throchanter

Question 96

p90(i)Diaphragm

Answer 96

→ separates abdominal- from thoracic cavity

• 3 parts:
  
  • costal, sternal, vertebral
• central tendinous part with attached muscle fibers around, innervated by phrenic nerve
• anchored to lumbar vertebrae by
  
  • right crus: attaches to L3 vert.
  • left crus: attaches to L2 vert.
• inferior borders:
  
  • Median-, Medial- and Lateral arcuate lig.
• Piercing structures:
  
  • Aorta, IVC
  • Esophagus w/ ant. + post. vagal trunks
  • hemi-azygous vein

Question 97

Diaphragm - Blood supply + Innervation

Answer 97

• Blood supply
  
  • superiorly:
    
    • branches of superior phrenic artery (from thoracic aorta) and internal thoracic artery
  • inferiorly:
    
    • inferior phrenic arteries (from abdominal aorta)
• Innervation
  
  • phrenic nerves (from C3-C5 spinal segments)

Question 98

Femoral canal

Answer 98

→ small compartment medial to femoral artery and vein, lateral to great saphenous vein

• inferior to inguinal ligament
• entrance: femoral ring (inferior to superficial inguinal ring)
• conical shape, about 2 cm long
• contains efferent lymph vessels

Question 99

Inguinal canal

Answer 99

→ slit-like passage above and parallel to the lower half of the inguinal ligament

• begins at deep inguinal ring
  
  • opening of ​tubular evagination of tranversal fascia which hosts:
    
    • men: the spermatic cord
    • women: round ligament of uterus
• ends at superficial inguinal ring
  
  • ​superior to pubic tubercle
  • in aponeurosis of external oblique m.

Question 100

Spermatic cord

Answer 100

• begins at deep inguinal ring, exits at superficial inguinal ring
• enclosed 3 layers
  
  1. internal spermatic fascia
  2. cremasteric fascia
  3. external spermatic fascia
• contents:
  
  • deferens duct
  • deferens duct artery (from inf. vesical artery)
  • testicular artery (from abdominal aorta)
  • pampiniform plexus of veins (to testicular veins)
  • cremasteric art. + vein
  • genital branch of genitofemoral nerve
  • lymph vessels

Question 101

Thoracolumbar fascia

Answer 101

→ covers deep muscles of the back and trunk

consists of 3 layers:

1. posterior layer
   
   • thick, attached to spinous processes of LV
   • extends laterally to cover erector spinae
2. middle layer
   
   • attached to transverse processes of LV
3. anterior layer
   
   • attached to transverse processes of LV
   • covers anterior surface of quadratus lumborum m.

Question 102

Lumbar plexus

Answer 102

• subcostal n.
• iliohypogastric n.
• ilioinguinal n.
• lat. cutaneous n.
• femoral n.
• genitofemoral n.
• obturator.