Yr3 Sem1

Question 1

Introduce the anterolateral Abdominal Wall

Answer 1

S: musculo-aponeurotic wall
F: Contracts to increase intra-abdominal pressure and provide trunk movement. Also distends to accommodate expansion due to ingestion, pregnancy, fat deposition or pathology
Location: found anterolateral over the abdominal cavity extending from the thoracic cage to the pelvic girdle

Question 2

External Oblique:

Answer 2

O: external surface of ribs 5-12
I: linea alba, pubic tubercle, anterior 1/2 iliac crest
N: thoracoabdominal n/subcostal n
A: flexion and rotation (contralateral) of the trunk , compression and support of the viscera
Fibre Direction: inferior and medial

Question 3

Internal Oblique:

Answer 3

O: Thoracolumbar fascia, Anterior 2/3 iliac crest, lateral 1/2 inguinal ligament
I: inferior border of ribs 10-12, linea alba, pectineal line via conjoint tendon
N: thoracoabdominal n/ first lumbar n
A: flexion and rotation (ipsilateral) of the trunk , compression and support of the viscera
Fibre Direction: changes around the ASIS. inferior to: run inferior and medial, At level: transversals medial, superior to: superior and medial

Question 4

Transversals Abdominals:

Answer 4

O: inferior surface of costal cartilage 7-12, thoracolumbar fascia, iliac crest and lateral 1/3 inguinal ligament
I: linea alba, pubic crest and pectineal line via the conjoint tendon
N: thoracoabdominal n/ first lumbar n
A: compression and support of the visceral
Fibre Direction: transverse medial, inferiorly runs inferior and medial with the internal oblique aponeurosis

Question 5

Rectus Abdominus

Answer 5

O: Pubic symphysis and pubic crest
I: xiphoid process and costal cartridges 5-7
N: thoracoabdominal n
A: Flexes the trunk, compresses and supports the abdominal viscera
Special feature: enclosed in the rectus sheath and anchored transversely

Question 6

What is the rectus sheath

Answer 6

is a strong but incomplete compartment in the aponeurosis between the anterolateral abdominal wall muscles. It contains the rectus abdominis, pyramidalis, superior and inferior epigastric arteries and veins, lymphatic vessels and distal portions of the thoracoabdominal nerves. It is formed by the decussation and interwoven aponeuroses of external and internal oblique and transverse abdominal muscles

Question 7

What is the line Alba

Answer 7

Along the length of the rectus sheath at the anterior median line the fibres of both the anterior and posterior walls interlace to form a strong median lattice running from the xiphoid process, narrowing at the level of the umbilicus to attach at the pubic symphysis

Question 8

Introduce the Inguinal Canal

Answer 8

S: in an anatomical passageway
F: serves as a retinaculum for muscular and neuromuscular structures that pass deep to the thigh
L: runs in an oblique inferior and medial direction across the anterolateral abdominal wall.

Question 9

What are the borders of the Inguinal Canal

Answer 9

Anterior: aponeurosis of the external oblique
Posterior: transversalis fascia and conjoint tendon of internal oblique and transverse abdominal
Floor: inguinal ligament
Roof: fibres of the internal oblique and transverse abdominals
deep inguinal ring: found in the transversalis fascia laterally
Superficial inguinal ring: found medially in the external oblique aponeurosis

Question 10

What are the contents of the inguinal canal

Answer 10

nerves, vessels, lymphatics
Males: spermatic cord
Females: round ligament of the uterus

Question 11

Introduce the Parietal Peritoneum

Answer 11

S: a double layer serous membrane
F: covers and contains the contents of the abdominal cavity
L: found on the internal surface of the abdominal wall
two layers: parietal and visceral, the parietal is the outer most layer and sensitive to pain, temperature, pressure and touch receiving blood and nerve supply from the same region as the wall it sits against. the visceral peritoneum covers the abdominal viscera and is sensitive only to stretch and tearing. receives blood and nerve supply from the organ it covers. These layers are separated by the peritoneal cavity

Question 12

Describe the peritoneal cavity

Answer 12

is a potential space between the two layers of the peritoneum. it is empty except for a thin layer of fluid that keeps the peritoneal surfaces moist and prevents friction.
it contains leukocytes and antibodies that resist infection.

Question 13

Describe Intra and Extra peritoneal organs

Answer 13

Intra: are almost completely covered with visceral peritoneum and are connected to the posterior abdominal wall by mesenteries
Extra: are external or posterior to the parietal peritoneum and only partially covered by the peritoneum, usually just one surface.

Question 14

What are the different parts of the peritoneum

Answer 14

Mesenteries: double layers of peritoneum that are continuous with the parietal and visceral peritoneum, resulting from invagination by organs. it connects organs to the posterior abdominal wall, and provides a passage for neuromuscular communication
Lesser Momentum: is a double layered fold of peritoneum that connects the lesser curvature of the stomach and proximal duodenum to the the liver at the fissure of the ligamentum venous and portages hepatic.
Greater Omentum: is a four-layers fold of peritoneum that hangs down from the greater curvature of the stomach and proximal duodenum. It descends to fold back and attach to the anterior surface of the transverse colon and its mesentery.

Question 15

What are peritoneal ligaments?

Answer 15

are double-layered aspects of peritoneum that connect an organ with another organ or to the abdominal wall

Question 16

What is the blood supply to the abdominal wall

Answer 16

Reflects the arrangement of the muscles. they have an oblique, circumferential pattern.
Superior epigastric a: direct continuation of the internal thoracic artery. Enters the rectus sheath through the posterior layer and supplies the superior rectus abdomens and anastomoses with the inferior epigastric
Inferior epigastric: arises from the external iliac artery superior to the inguinal ligament. runs superior to the transversalis fascia to enter the rectus sheath below the arcuate line.

Question 17

What are the branches of the abdominal aorta

Answer 17

Celiac trunk (level of T12)
Superior Mesenteric (L1)
Inferior Mesenteric (L3)
Suprarenal (L1) Paired
Renal (L1/2) paired 
Gonadal (ovarian or testicular) (L2) paired

Question 18

What are the branches of the celiac trunk and what do they supply

Answer 18

common hepatic > splits into the proper hepatic and gasproduodenal with right gastric branch (lesser curvature) > proper hepatic splits into Lt and Rt to supply liver lobes/ gasproduodenal branches into right gastro-omental (greater curvature), superior anterior/posterior pancreatiocduodenal (pylorus, duodenum and head of pancreas)
left gastric supplies the lesser curvature
splenic > gives off pancreatic branches and short gastric (fundus of stomach) before supplying the spleen

Question 19

What are the branches of the superior mesenteric artery and what do they supply

Answer 19

iliocolic artery (iliececal junction, ceacum) > appendicular artery (appendix)
right colic artery (ascending colon)
middle colic artery (hepatic flexure and transverse colon)
intestinal arteries (10-15 br. to small intestines)
inferior anterior/posterior pancreaticoduodenal artery (duodenum/head of pancreas)

Question 20

What is the venous drainage of the abdominal wall

Answer 20

superior epigastric/vessels from muscle-phrenic vessels of internal thoracic vessels
inferior epigastric/deep circumflex epigastric vessels from femoral and saphenous veins
11th posterior intercostal vessels

Question 21

what is the main venous drainage of the abdominal

Answer 21

inferior vena cava - begins at the level of L5 at union of the common iliac veins to the canal opening in the diaphragm to the heart
portal vein - is the visceral drainage of the abdominal into the liver to the IVC

Question 22

what are the main lymphatic drainage of the abdominal wall

Answer 22

Superficial:
Above transumbilical line: axillary and parasternal nodes
Below transumbilical line: superficial inguinal nodes
Deep:
external iliac, common iliac and right and left lumbar nodes

Question 23

What are the basic layers of the gastrointestinal wall?

Answer 23

Mucosa - layer of epithelial tissue on a layer of connective. three sub layers: surface epithelium, lamina proprietary and muscular layer
Submucosa
Muscularis Externa - contains a circular and longitudinal layer
Serosa or Adventitia - serosa for intra peritoneal, adventitia for retroperitoneal on walls not in contact with parietal peritoneum

Question 24

Introduce the Oesophagus

Answer 24

L: extends from the pharynx in the mid neck and descends through the thorax on the anterior surface of the vertebral column, passing through the oesophageal hiatus to the stomach
S: is a long muscular tube with three sections, a cervical, thoracic and abdominal. with four constrictor points. The Upper oesophageal sphincters located at the level of the cricoid cartilage, the brachioaortic where the aorta and left main bronchus cross the oesophagus as well as the lower oesophageal sphincter. this is more functional as it is intrinsically a small thickening in the circular muscle layer of the wall reinforced extrinsically by the diaphragm
F: utilises peristalsis to move food bolus from the oral cavity to the stomach

Question 25

Talk through the histology of the oesophagus

Answer 25

the oesophagus is a muscular tube with a mucous membrane. The lumen is lined by stratified squamous epithelium (E) which changes to simple columnar epithelium at the gastroesophagel junction. Underlying this is the lamina propria (Ly) which contains scattered lymphoid aggregates but is extremely thin. the muscular mucosa (MM) is next. when the oesophagus does not contain bolus it lies flat and these layers are squished into deep folds. The submucosa (SM) is made of areola connective tissue and contains seromucosa glands that aid the lubrication of the lumen. the Muscular Externa contains muscle fibres with two main fibre directions, an inner circular (CM) layer and an outer longitudinal layer (LM) the superior 1/3 of the oesophagus contains skeletal muscle under voluntary control via the recurrent laryngeal nerve. the inferior 1/3 is smooth muscle and the middle 1/3 contains a mix of both fibres. the smooth muscle receives parasympathetic supply from the vagus nerve and sympathetic supply from the cervical sympathetic ganglion, cardiopulmonary splanchnic and abdominopelvic splanchnic fibres. the outer most layer is the adventitia a fibrous connective tissue layer. In the abdomen the oesophagus is retroperitoneal but the stomach is intraperitoneal so the anterior surface of the muscular tube has a serous outer layer.

Question 26

Discuss the neurovascular supply of the oesophagus

Answer 26

Arteries: inferior thyroid branch, oesophageal arteries (ventral paired br. of aorta), left gastric and left phrenic Venous: inferior thyroid v (follows artery), oesophageal v > azygous veins, left gastric > portal vein Lymph: paratracheal, inf. deep cervical, posterior mediastinal and left gastric nodes Neural: intrinsic: ENS extrinsic: para: vagus nerve symph: cervical sympathetic ganglion, cardiopulmonary and abdominopelvic splanchnic

Question 27

Introduce the stomach

Answer 27

L: rests in the epigastric region and some of the left hypochondriac it is the continuation of the oesophagus in the GIT and connects to the duodenum next. it is inferior to the diaphragm and anterior to the pancreas S: J-shaped organ with three external muscular layers (longitudinal, circular and oblique) and internal surface layer contains longitudinal folds or rugae ma elf simple columnar epithelium F: it is a temporary storage tank that also provides mechanical and chemical breakdown of bolus into chyme. it continues the peristaltic contraction of the oesophagus to churn the bolus, breaking it down and mixing it with gastric juices. This contains enzymes that breakdown certain molecules.

Question 28

Identify the landmarks of the stomach

Answer 28

- cardia - cardiac notch - funds - body - lesser curvature - greater curvature - pyloric region - pyloric antrum - pyloric canal - pylorus - angular notch

Question 29

Describe the peritoneal relationships of the stomach

Answer 29

as the stomach is intra-peritoneal there are two main folds int he lining that connect with other organs the greater omentum: Attached to the greater curvature of the stomach and proximal duodenum, it descends to fold back and attach to the transverse colon and transverse mesocolon. the lesser omentum:Connects the lesser curvature of the stomach and the proximal duodenum to the liver.

Question 30

Explain the neurovascular supply of the stomach

Answer 30

A: celiac trunk > Lt/Rt gastric, short gastric & Lt/Rt gastro-omental V: Lt/Rt gastric veins > portal vein, Short gastric & left gastro-omental > splenic v, right gastro-omental > superior mesenteric v > portal v L: Gastric and gastro-omental nodes > celiac nodes N: intrinsic: ENS extrinsic: para: CNX vagus symptoms: T6-9 greater splanchnic n through celiac plexus visceral afferent

Question 31

Discuss the histology of the stomach

Answer 31

The whole stomach mucosa is a tubular glandular form, thrown into rugae when contracted. It is a layer pitted with gastric pits that lead to tubular glands that produce gastric juices. there are a number of cell types in these pits, that's secretion is stimulated by prostaglandins: - mucosal neck cells - parietal cells: secrete HCL which contributes to the acidity and intrinsic factor that helps with the reabsorption of vitamin B12 - chief cells: produce pepsinogen and gastric lipase, pepsinogen is converted to pepsin by HCL - enter-endocrine cells: secrete hormones and chemical mediators: gastrin: controls secretory activity of the stomach, histamine and serotonin muscular mucosa layer Submucosa is relatively loose, distensable tissue, highly vascular, thin serosa layer muscular propria: has an additional inner oblique layer to assist in the grinding and churning of bolus into chyme and mixing through the gastric juices.

Question 32

Describe the histology of the gastroesophagel junction

Answer 32

L: gastroesophagel junction is located where the oesophagus meets the stomach inferior to the diaphragm. S: this is a physiological sphincter rather than anatomical, there is a slight thickening in the circular muscle fibres of the muscular proprietary, that is reinforced by the diaphragm and the mucosal layer goes through a destinct change to accomodate the change in environments F: prevents bolus from moving back through the lumen to the oesophagus Is the space where the oesophagus meets the stomach near the lower oesophageal sphincter. It is the abrupt transition from protective squamous epithelium of the oesophagus to the tightly packed glandular secretory mucosa of the stomach. the muscular mucosa is continues but less distinctive int he stomach while the submucosa and muscular proprietary are uninterrupted

Question 33

Explain the mechanisms behind gastric emptying

Answer 33

gastric emptying is under both hormonal and neural mechanisms. Nervous: duodenal receptors are sensitive to distention and low pH, these stimuli cause reflex inhibition of the ENS and Vagus which reduce secretions and mobility. duodenal hormones are also released in response to the presence of fatty, acidic chyme. these are Cholecystokinin, gastric inhibitory peptide and secretin.

Question 34

Introduce the small intestines

Answer 34

L: the small intestines extends from the pyloric sphincter to the ileoceacal junction, inferior to the stomach an transverse colon. S: is the extension of the GIT as a convoluted muscular tube, lined with simple columnar epithelium and subdivided into three regions. the duodenum, jejunum and the ilium. It is an intra-peritoneal organ except for the duodenum which is retroperitoneal. F: the small intestines primarily receive secretions from the liver and pancreas that helps to chemically digest food for absorption. they mechanically breakdown chyme and using peristaltic activity to transport undigested materials to the large intestine

Question 35

what are three unique features of the small intestines:

Answer 35

1. circular folds: the muscosa and submucosa are arranged in permanent circular folds that force chyme to spiral through the lumen 2. villi: are finger like projections of the mucosa with intestinal crypts between that contain 5 types of cells 3. microvilli: exist on each villi that contain brush border enzymes that assist in the digestion of food.

Question 36

what histological factor is different in duodenum?

Answer 36

the duodenum contains brunners glands in the submucosa. these release a mucous rich alkaline secretion that neutralises the acidity of the stomach chyme, increases conditions for optimal enzyme activity and lubricates the walls.

Question 37

Introduce the parts of the duodenum

Answer 37

the duodenum has four regions. D1: the immediate continuation from the pyloric sphincter and superior aspect of the duodenum, it is intra-peritoneal. D2: is the descending part and receives the liver and pancreatic secretions via the major and minor duodenal papilla. D3: is the horizontal aspect that sits about the level of L3 D4: ascends to the level of L2 then angles sharply to form the duodenojejunal flexure.

Question 38

Discuss the neurovascular supply of the duodenum

Answer 38

A: gasproduodenal, superior and inferior anterior and posterior pancreaticoduodenal arteries V: follow the arteries > portal vein L: pancreaticoduodenal nodes and superior mesenteric nodes N: intrinsic: ENS Extrinsic: para: CNX vagus Symp: greater and lesser splanchnic (T5-9) visceral afferents

Question 39

Introduce the Jejunum and Ileum

Answer 39

L: extend from the deuodenojejunal flexure the to the ilioceacal junction. S: long convoluted muscular tube. the Jejunum sits mostly in the upper left quadrant while the ileum rests mostly in the right lower quadrant. these are intra-peritoneal organs attached to the posterior abdominal wall via a fan shaped mesentery

Question 40

Discuss the neurovacular supply of the jejunum and ileum

Answer 40

A: intestinal arteries off the superior mesenteric artery V: superior mesenteric vein > portal vein L: superior mesenteric nodes N: intrinsic: ENS Extrinsic: para: CNX vagus symp: greater and lesser splanchnic (T5-9) visceral afferents

Question 41

Explain the histology of the small intestines

Answer 41

the small intestines contain a number of cellular changes to accommodate for its specialised function in absorption. Cells of the villi and crypts: - enterocytes: are absorptive cells endowed with microvilli that secrete intestinal juices in the crypts - goblet cells: produce alkaline mucous but relies on prostaglandin E2 - Enteroendocrine: secrete hormones such as CCK and secretin - panted cells: release antimicrobial agents - stem cells: renew the epithelium every 3-5 days

Question 42

Introduce the Large intestine

Answer 42

L: the large intestine extends from the iliocaecal junction to the anus, it runs around the periphery of the small intestines, starting in the right lower quadrant. S: long muscular tube continuation of the GIT, it is wider but smaller than the small intestine and subdivided into five parts. the caecum, colon, rectum, anal canal and anus. the ascending and descending colons of the large intestine are retro-peritoneal. F: the large intestinal performs minimal to no digestion, primarily it absorbs water, electrolytes and vitamins, uses austral contractions to propels faecal matter to the anal canal for defecation

Question 43

identify important landmarks of the large intestine

Answer 43

- caecum: first part of the large intestine, receives chyme from the ileum and continuous with the ascending colon. sits in the RLQ corresponding with the right iliac fossa. intraperitoneal - appendix: blind intestinal out pouch at the posteromedial aspect of the caecum. has a short mesoappendix between the terminal ileum, caecum and appendix. intraperitoneal - ascending colon: passes superiorly on the right side from the caecum to the liver. joins the transverse colon at the hepatic flexure in RUQ. Retroperitoneal, anterior and lateral surfaces covered - hepatic flexure: inferior to the liver - transverse colon: largest and most mobile section. hangs across the abdomen at the level of the umbilicus passing to the splenic flexure. has the transverse mesocolon and attachment to the greater omentum. intraperitoneal - splenic flexure: more acute, superior and less mobile. attaches via the pheronicocolic ligament to the diaphragm - descending colon: passes inferiorly to the iliac fossa and is continuous with the sigmoid colon, retroperitoneal, anterior and lateral covered. - sigmoid colon: s-shaped loop extends from the iliac fossa to S3 links to the rectum. intraperitoneal, mesentery - rectum: teniae coli end at the rectosigmoid junction. follows curve of the sacrum and coccyx. ends at tip of coccyx to turn posteroinferior as anorectal flexure. rectal ampulla. retroperitoneal. superior 1/3 anterolateral, middle 1/3 anterior, inferior 1/3 sub-peritoneal - anal canal: terminal aspect of the large intestines between the pelvic diaphragm and anus. - anus

Question 44

What are three unique features of the large intestine

Answer 44

1. tennis coli: longitudinal is separated into three distinct thickened bands 2. haustra: are sacs caused by the muscular tone puckering the colon wall 3. omental appendices: are small fatty projections of the omentum that hang from the surface of the colon

Question 45

what is the blood supply of the large intestine

Answer 45

- superior mesenteric artery: ilioceacal artery > caecum, appendicular a > appendix, right colic artery > ascending colon and hepatic flexure, middle colic a > transverse colon - inferior mesenteric artery: left colic a > splenic flexure and descending colon, sigmoid a > sigmoid colon, superior rectal artery > superior aspect of the rectum (above the pectoneal line) venous drainage follows the same pathway except that the inferior mesenteric vein drains into the splenic vein and the superior mesenteric vein meets the splenic to form the portal vein

Question 46

What is the nervous supply and lymphatic drainage of the large intestine

Answer 46

Intrinsic: ENS Extrinsic: - Para: Vagus n fro appendix to splenic flexure, then pelvic splanchnic (S2-4) Symp: appendix to splenic flexure > T10-12 descending/sigmoid colon > lumbar region of the sympathetic trunk and superior hypogastric plexus lymphatic drainage: Caecum/Appendix: ileocolic nodes > SM nodes Ascending: epicolic and parabolic > ileocolic and Rt colic > SM nodes Transverse: middle colic > SM nodes Descending/Sigmoid: epicolic and parabolic > IM nodes

Question 47

Describe the Histology of the large intestine

Answer 47

Mucosa: simple columnar epithelium but thicker with deeper crypts. Has more goblet cells that produce mucous to ease passage of faecal matter. unlike small intestines does not contain brush border enzymes, villi or circular folds.

Question 48

Describe the histology of the appendix

Answer 48

the appendix is suspended via the mesoappendix, which provides neurovascular passage. there is a serosa layer as it is intra-peritoneal. the lumen contains many follicles that bulge inward ad contain germinal centres. these hold masses of lymphoid tissues, it produces and stores lymphocytes, is a reservoir for good bacteria and recolonises the gut

Question 49

introduce the appendix

Answer 49

L: arises from the caecum, it sits roughly 2/3 of the way from the umbilicus to the ASIS. S: is a worm like projections that is intraperitoneal and contained in the mesoapendix that stretches between the terminal ilium, caecum and appendix. F: produces and stores lymphocytes and is a reservoir for beneficial bacteria

Question 50

Introduce the Liver

Answer 50

L: the liver is located in the right upper quadrant with a small extension into the left upper quadrant. it sits against the inferior aspect of the diaphragm in the right dome. S: the liver is a large wedge shaped organ that is reddish-brown in colour. It has four lobes, a right, left, quadrate and caudate F: there ar five main functions of the liver 1. synthesis: bile, plasma proteins and hormones 2. detoxify: drugs/alcohol 3. metabolism and storage: fat, carbohydrates, amino acids, vitamins and minerals 4. excretion: bilirubin in bile 5: immune function: phagocytic activity

Question 51

Identify the surfaces, lobes and landmarks of the liver

Answer 51

Diaphragmatic: smooth convex surface that rests in the right concavity of the diaphragm, covered with peritoneum except in the bare area. Visceral: covered with peritoneum except near the gall bladder and aorta hepatis. is the inferior, posterior aspect Right, Left, caudate (upper) and quadrate (lower) lobes Porta Hepatis: is a transverse fissure on the visceral surface between the caudate and quadrate lobes and contains the portal vein, hepatic artery, nerve plexus and duct as well as lymphatic vessels. - right/Left/caudate/quadrate lobes - bare area - triangular ligaments: peritoneal folds that connect to the diaphragm, left is continuous with the falciform ligament - falciform ligament: connects the liver to the anterior abdominal wall/diaphragm - round ligament: fibrous remnant of the umbilical vein, found on the free edge of the falciform ligament - ligamentum venousum: fibrous remand of the ductus venosus, allowed blood to bypass the liver in the foetus - found on the visceral surface in the umbilical fissure - coronary ligament: peritoneal reflection from the liver to the diaphragm - marks the bare area - sagittal fissure - hepatic veins and IVC - gall bladder - apex - inferior border

Question 52

what are the peritoneal relations of the liver

Answer 52

the lesser omentum: connects the lesser curvature of the stomach and proximal part of the duodenum to the liver. two ligaments assist this - hepatoduodenal ligament - hepatogastric ligament the lesser omentum encloses the the portal triad

Question 53

Explain the neurovascular supply to the liver

Answer 53

A: portal vein (70% - nutrient rich) and hepatic artery (30% - oxygenated blood) V: hepatic veins > IVC L: superficial lymphatics > hepatic nodes > celiac or phrenic nodes > posterior mediastinal nodes deep lymphatics > hepatic nodes N: hepatic plexus: para: CNX Vagus / symp: T5-9 via celiac plexus

Question 54

Describe the histology of the liver

Answer 54

functioning unit of a liver is lobule containing many hepatocytes. small sesame-seed size in a hexagon shape. Each hepatocyte radiates outwards from a central vein, each corner of the lobule contains a portal tract with a bile duct, hepatic artery and vein. blood flows towards the central vein via sinusoids while bile flows away from the central vein to the portal tract via bile canaliculi

Question 55

introduce the gall bladder

Answer 55

L: sits against the inferior visceral surface of the liver in the gall bladder fossa S: pear shaped muscular sac F: storage and concentration of bile

Question 56

What are the landmarks of the gall bladder

Answer 56

- fundus: wide end, projects from the inferior border of the liver - body: contacts the visceral surface of the liver - neck: narrows tapered region, makes an S-shape bend and continues as the cystic duct

Question 57

Explain the neurovascular supply to the gall bladder

Answer 57

A: cystic a, br. hepatic a V: cystic v > directly into the liver or portal v L: liver > cystic nodes > hepatic nodes and celiac nodes N: para: CNX vagus symp: splanchnic n T5-9 via celiac plexus sensory: right phrenic n

Question 58

Describe the histology of the gall bladder

Answer 58

Mucosa: made of simple columnar epithelium that possess microvilli for absorption, it is thrown into honeycomb like folds when contracting - has nomuscularis mucosa or submucosa Muscularis: smooth muscle, collagen and elastin and contracts in response to cholecystokinin and vagal stimulation Adventitia/serosa: the surface in contact with the liver is covered with advntitia while the rest is in contact with the peritoneum and so covered in serosa

Question 59

Introduce the pancreas

Answer 59

L: is located in the abdominal cavity in the epigastric and left hypochondriac regions. it sits in the C-shape of the duodenum extending its tail laterally to the left to rest against the spleen S: tadpole-shaped gland with an uncinate, head, neck, body and tail. Contains both acinar cells and pancreatic islets. is a retroperitoneal organ except for the tail which passes between the layers of the splenorenal ligament F: exocrine and endocrine functions.

Question 60

What are the important landmarks and structures of the pancreas

Answer 60

- head: sits in the C of the duodenum - uncinate process: is the lower part of the head that projects upwards and to the left - neck: holds the groove for the gasproduodenal artery, superiorly the SMV and splenic v meet to form the portal vein - body: crosses the aorta at the level of L2, anteriorly covered by peritoneum - Tail: anterior to the left kidney, closely related to the hilum of the spleen and splenic flexure. - main pancreatic duct: begins in the tail and runs toward the head, unites with the bile duct to form the hepatopancreatic ampulla which opens into the duodenum via the major duodenal papilla - accessory duct: drains the inferior part of the head and opens into the minor duodenal papilla - sphincters: sphincter of the pancreatic duct, sphincter of the bile duct, hepatopancriatic sphincter

Question 61

What is the neurovascular supply of the pancrease

Answer 61

A: pancreatic a, superior and inferior anterior and posterior pancreaticoduodenal a V: same as a. inferior pancreaticoduodenal v drain into splenic v meets SMV to form portal v L: pancreaticosplenic nodes > celiac, hepatic and superior mesenteric nodes N: Para: CNX Vagus Symp: abdominopelvic splanchnic (T5-9)

Question 62

Explain the histology of the pancreas

Answer 62

has a thin collagenous capsule that extends inward as delicate septa between the lobules Exocrine: acinar cells - form the bulk of the pancreas - secretes enzyme rich juice into the ductal system - ductal cells secrete water and HCO3 Endocrine: pancreatic islets - contain 4 main hormone producing cell types - alpha cells: glucagon (increase blood sugar) - beta: insulin (decrease blood sugar) - delta: somatostatin -PP cells: pancreatic peptide

Question 63

Explain the neurovascular supply to the pancreas

Answer 63

A: pancreatic branches off the splenic a, anterior and posterior branches of the superior and inferior pancreaticoduodenal a V: pancreatic veins > splenic vein L: pancreaticosplenic nodes > hepatic, celiac or superior mesenteric nodes N: para: CNX Vagus symp: T5-9 abdominopelvic splanchnic via celiac ganglion

Question 64

what is the flow of lymphatics

Answer 64

capillaries > collecting vessels > trunks > ducts

Question 65

what factors affect lymphatic flow

Answer 65

- rhythmic contraction of lymphatic vessels using smooth muscle and pulsations from arteries - intermittent pressure on lymphatic vessels due to skeletal muscle contraction and movement of viscera - pressure changes in the thorax due to respiration

Question 66

introduce lymph nodes

Answer 66

L: are widely distributed and clustered along lymphatic vessels S: secondary lymphoid organs vary in size from pin head to olive and larger in pathology. contain a dense fibrous capsule with an internal storm of reticular connective tissue compartmentalised by trabeculae F: houses lymphocytes and macrophages, is a site of immune system activation and filtering of lymph

Question 67

Describe lymphoid histology

Answer 67

``` C = collagenous capsule Cx = cortex: contains B cells PF = primary follicle inactive B cells, respond to antigens and proliferate and maturation SF = secondary follicle - active immune response , germinal centre P = paracortex: site of T-cell maturation and expansion T = trabeculae: extensions of the fibrous capsule S = sub capsular sinus M = medulla MC = medullary cord thin extensions from the cortex, contain B and T cells MS = medullary sinus H = hilum: efferent vessels drain efferent lymph ```

Question 68

Explain the pathway of nodal circulation

Answer 68

afferent vessel > subcapsular sinus > medullary sinus > exits through efferent vessels at the hilum

Question 69

Introduce the spleen

Answer 69

L: left hypochondriac region posterior to stomach deep to ribs 9-11 on splenic flexure S: is the largest lymphatic organ, secondary, dark red and highly vascular F: has a number of functions, immune functions involve lymphocyte proliferation, surveillance and response, filters blood for macrophages to remove debris and foreign matters, reservoir for blood, platelets and monocytes, recycles RBC by-products such as iron and is involved in erythropoiesis in foetus

Question 70

Identify the relevant landmarks, ligaments, surfaces and borders

Answer 70

``` surfaces: diaphragmatic, visceral Borders: superior, anterior and inferior ligaments: gastrosplenic and splenorenal landmarks: - gastric impression - renal impression - colic impression - hilum: splenic vessels - site of pancreas tail connection ```

Question 71

Describe the neurovascular supply of the spleen

Answer 71

``` A: splenic a divides at the hilum V: splenic v > forms the portal v L: nodes in hilum > pancreaticosplenic nodes > celiac, hepatic or superior mesenteric nodes N: para: CNX Vagus symp: abdominopelvic splanchnic T6-10 ```

Question 72

Discuss the histology of the spleen

Answer 72

C: thin fibroelastic capsule T: capsule extensions into the spleen to form trabeculae RP: red pulp, abundant. Erythrocytes and macrophages engulf and destroy old RBC and foreign matters WP: scarce islands of white pulp amongst the red. provide the immune functions, is mostly lymphocytes suspended on reticular fibres

Question 73

Introduce the Kidney

Answer 73

L: found on the posterior abdominal wall, extending from approximately T12 to L3. they are retroperitoneal and the right kidney is crowned by the liver and sits lower than the left S: paired bean shaped organs of the urinary system F: urine formation: filters blood, regulate metabolic waste and maintains the acid-base balance also has an endocrine and metabolic function in that it is involved in erythropoiesis, produces renin, converts vitamin D to its active form and gluconeogenesis

Question 74

Explain the neurovascular supply of the kidneys

Answer 74

``` A: renal a > segmental a > interlobular a > arcuate a > cortical radiate > afferent arterioles > glomerular capillaries V: Renal v L: para-aortic nodes N: para: CNX Vagus symp: T10-12 splanchnic n visceral afferents ```

Question 75

Identify the gross structure of the kidney

Answer 75

Cortex: beneath the capsule Medulla: arranged as pyramids with papilla and base - pyramids have a striped appearance due to the parallel collecting tubules - renal columns: inward extensions of the cortical tissue - one pyramid and its surrounding cortical tissue = one kidney lobe Renal Pelvis: drains urine from the renal papillae into the minor calyces into the major calyces and into the renal pelvis and finally into the ureters through the hilum

Question 76

What are the functional unit of the kidney

Answer 76

Nephrons. there are two types: - cortical nephron: majority of nephrons. located predominantly in the cortex - juxtamedullary nephron: originates close to the cortex-medulla junction and posses long nephrons loops that extend deep into the medulla. these create osmotic gradients allowing for the creation of concentrated urine

Question 77

What are key microscopic features

Answer 77

Renal corpuscle: - glomerulus: bundle of capillaries that receive blood, small with fenestrations for easy filtration - glomerular capsule: cup shaped hollow structure that surrounds the glomerulus, continuous with the renal tubule Renal tubules: - PCT: receives filtrate lined with cuboidal cells that possess microvilli - Loop of Henle: descending limb is squamous cells and is the thin segment, ascending is cuboidal and columnar cells and is thick segment - DCT: cuboidal cells no microvilli, conveys urine to the collecting duct - collecting duct: receives filtrate from many nephrons and allows for last adjustments to concentration and content

Question 78

explain the histology of the kidney

Answer 78

``` Cp: fibrous capsule C: cortex M: medulla P: papillae U: ureter H: hilum ```

Question 79

Introduce the ureters

Answer 79

L: extend from the hilum of the kidney along poses to the bifurcation of the iliac artery, cross the SIJ to empty into the bladder S: paired narrow tubes lined with transitional epithelium F: uses peristalsis and glomerular pressure t move urine from the kidneys to the bladder

Question 80

Explain the neurovascular supply

Answer 80

A: Upper: ureteric br of renal a Middle: br of aorta, gonadal and iliac a Lower: superior and inferior vesicle and uterine a V: same as a L: abdominal: para-aortic, pelvic: common iliac and internal iliac N: para: pelvic splanchnic S2-4 symp: T10-12 hypogastric, renal and coeliac plexus

Question 81

Introduce the bladder

Answer 81

L: anterior to the rectum/vagina in the pelvic cavity when empty, when full distends up into the abdominal cavity S: hollow visceral organ with strong muscular walls. is sub-peritoneal superior surface serosa, and surrounded by vesicle fascia - Female: the bladder contacts the uterus and vagina with the utter-vesicular pouch in between - Male: prostate gland is situated inferior to the neck with the seminal vesicles, vas deferent and rectoviseral pouch F: is a temporary reservoir for urine

Question 82

what is the neurovascular supply of the bladder?

Answer 82

A: internal iliac has two main branches: - superior vesicle: anterior and superior aspect - inferior vesicle(M)/vaginal(F): fundus and neck V: as above L: superior surface > external iliac nodes fundus > internal iliac nodes N: para: pelvic splanchnic S2-4 symp: hypogastric plexus T10-L2

Question 83

Identify the surfaces, borders and landmarks of the bladder

Answer 83

surfaces: superior, inferior/posterior and inferior/lateral borders: anterior landmarks: - ureters - urachus - apex - base - body - neck internal: - detrusor muscle - rugae - ureteric orifice - trigone - bladder neck - internal urethral orifice/sphincter - urethra - prostate

Question 84

describe the histology of the bladder

Answer 84

mucosa: is lined with transitional epithelium thrown into rugae in relaxed state Muscularis: detrusor muscle which has inner and outer longitudinal fibres and a middle circular layer Adventitia

Question 85

Introduce the male urethra

Answer 85

L: extends fro the bladder neck through the prostate and entire corpus spongiosum to the urethral orifice at the tip of the penis. S: a long thin tube with three regions, a prismatic, intermediate and spongy. F: the male urethra serves both a urinary and a reproductive function

Question 86

Identify the regions and sphincters of the male urethra

Answer 86

Prostatic: is the shortest aspect of the urethra that runs close to the anterior surface of the prostate and receives the ejaculatory ducts Intermediate: is the shortest aspect, running from the apex of the prostate to the bulb of the penis, surrounded extrinsically by the external urethral sphincter and perineal membrane which contains the bulbourethral gland Spongy: is the longest part and passes through the bulb and corpus spongiosum of the penis. the bulbourethral ducts open into the proximal aspect and the lining contains mucous-secreting glands along its length. it ends at the external urethral orifice Internal Urethral Sphincter: formed by the thickening of the detrusor muscle at the neck of the bladder. involuntary, sympathetic fibres keep tonically contracted External Urethral Sphincter: is composed of striated muscle and is under voluntary control, innervated by thee perineal br of the pudendal n. surrounds the intermediate urethra

Question 87

Explain the histology of the male urethra

Answer 87

Mucosa: transitional epithelium lining with exception of the navicular fossa where it is stratified squamous epithelium which is continuous with the epithelium of the glans penis. contains mucous-secreting glands that produce a protective mucous layer Muscular: smooth muscle continuation of the bladder. three layers, inner and outer longitudinal and middle circular

Question 88

What is the neurovascular supply of the male urethra:

Answer 88

A: internal pudendal a < internal iliac a V: internal pudendal v L: internal and external iliac and deep inguinal nodes N: Spongy and EUS: pudendal n (s2-4) intermediate and prostatic: inferior hypogastric plexus - symp: T10-L2 - para: pelvic splanchnic (s2-4) - visceral afferents

Question 89

Introduce the female urethra:

Answer 89

L: relatively short passes anteroinferior from bladder neck to the external urethral orifice S: short, straight muscular tube, embedded in the anterior vaginal wall F: urinary function only

Question 90

Explain the relevant sphincters

Answer 90

Internal urethral sphincter: located at the bladder-urethral junction, formed by the continuation of the detrusor muscle. involuntary control External urethral sphincter: formed by a circular striated muscle surrounding the urethra where it passes through the pelvic floor. voluntary control - pudendal n (s2-4)

Question 91

Describe the histology of the female urethra:

Answer 91

Mucosa: is lined with non-keratinised stratified squamous epithelium contains mucous glands largest are the paired paraurethral glands which are equivalent of the prostate gland. drain via common duct just inside the orifice.

Question 92

What is the neurovascular supply of the female urethra

Answer 92

A: upper: vaaginal a lower: internal pudendal a V: vesicle plexus > internal pudendal v L: internal iliac and some into the external iliac node s