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Anatomy Flashcards

Anatomy of the Upper GI Tract - Seaneen McDougall

1
Q

what are the 3 pairs of muscles responsible for closing the jaw?

A

Masseter
Temporalis
Medial Pterygoid

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2
Q

what is the pair of muscles responsible for opening the jaw?

A

Lateral Pterygoid

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3
Q

what is the nerve division which supplies the jaw muscles?

A

mandibular division of trigeminal nerve - CN V3

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4
Q

What is the name of the joint where the jaw moves?

A

temporomandibular joint

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5
Q

what are the different regions of the pharynx?

A

nasal pharynx
oropharynx
laryngopharynx

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6
Q

How many teeth are in a complete set of teeth?

A

32 teeth

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7
Q

When do people typically have their full set of teeth?

A

age 18 but is expected by age 25

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8
Q

Why should you always ask if the patient has any loose teeth or fillings?

A

they are a choking hazard or aspiration risk

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9
Q

what are the 3 pairs of major salivary glands?

A

parotid (just in front of ear)
submandibular (under the mandible)
sublingual (under the tongue)
there are also loads of minor salivary glands

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10
Q

Where do each of the major salivary glands ducts enter into the mouth?

A

parotid - on the cheek in line with the 2nd molar
submandibular
sublingual - many ducts at the base of the mouth

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11
Q

What does the CN VII supply?

A

Taste ant. 2/3rds tongue
Muscles of facial expression
Glands in floor of mouth

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12
Q

What is the function of the extrinsic muscles of the tongue?

A

to change the position of the tongue during mastication, swallowing and speech

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13
Q

What are the functions of the intrinsic muscles?

A

modify the shape of the tongue during function

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14
Q

What nerve supplies the muscles of the tongue?

A

All of the muscles of the tongue are supplied by CN XII (hypoglossal) except for the palatoglossus

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15
Q

What does the patient have to do when you are inserting an endoscope?

A

They have to swallow in order to override the gag reflex

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16
Q

What happens in swallowing?

A
  1. close the lips to prevent drooling (orbicularis oris & cranial nerve VII)
  2. the tongue (cranial nerve XII) pushes the bolus posteriorly towards the oropharynx
  3. sequentially contract the pharyngeal constrictor muscles (cranial nerve X) to push the bolus inferiorly towards the oesophagus
  4. at the same time the inner longitudinal layer of pharyngeal muscles (cranial nerves IX & X) contracts to raise the larynx, shortening the pharynx and closing off the laryngeal inlet to help prevent aspiration
  5. the bolus reaches the oesophagus
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17
Q

Where in the neck does the oesophagus sit?

A

Just posterior to the trachea

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18
Q

What are the structures which which cause constriction in the oesophagus?

A 
Cervical constriction
Cricopharyngeus muscle (the upper oesophargeal sphincter at rib 1, root of the neck)
Thoracic constriction(s)
due to the arch of aorta and the left main bronchus (posterior to the heart)
Diaphragmatic constriction
Result of passing through diaphragm lower oesophageal sphincter (C10), oesophagus then immediateky connects with the stomach
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19
Q

What is the articular tubercle?

A

The tubercle which lies just anterior to the TMJ and helps to prevent dislocation of the joint

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20
Q

What is the course of the CN V3?

A

It comes from the pons (part of the brainstem) through the foramen ovale to the muscles of mastication and the sensory area

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21
Q

What is the name for the upper dental arch?

A

maxillary

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22
Q

What is the name for the lower dental arch?

A

mandibular

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23
Q

What nerve is responsible for sensation of the superior half of the gums (gingiva) and the palate?

A

CN V2

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24
Q

What nerve is responsible for sensation of the inferior half of the gums (gingiva) and the palate?

A

CN V3

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25
Q

What is the course of CN V2 (the maxillary division of trigeminal nerve)?

A

from pons, through the foramen rotundum to the sensory area (mid-face)

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26
Q

What does local anaesthetic spray do?

A

It blocks the sensory action potentials of CN V2, CN V3, CN VII and CN IX

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27
Q

What nerves are responsible for sensation in the anterior 2/3rds of the tongue?

A

the horizontal part of the tongue within the oral cavity
general sensation = CN V3
special sensation = CN VII

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28
Q

What nerves are responsible for sensation in the posterior 1/3rd of the tongue?

A

the vertical segment, no in the oral cavity

general & special sensation = CN IX

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29
Q

What is the course of CN VII?

A

from the pontomedullary junction through the temporal bone via the internal acoustic meatus then stylomastoid foramen.
Supplies taste in the anterior 2/3rds of the tongue the muscles of facial expression and the glands in the floor of the mouth.

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30
Q

What is the course of CN IX?

A

from the medulla through the jugular foramen to the posterior wall of the oropharynx (sensory), parotid gland (secretomotor) and posterior 1/3rd tongue (sensation and taste)

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31
Q

What are the 4 pairs of extrinsic tongue muscles?

A

palatoglossus
styloglossus
hyoglossus
genioglossus

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32
Q

What is the course of CN XII?

A

from medulla, through the hypoglossal canal to the extrinsic and intrinsic muscles of the tongue (except the palatolossus)

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33
Q

What are the properties of the circular muscles within the pharynx?

A

circular constrictor muscles overlap with each other in the external layer, they are voluntary muscles which contract sequentially, they all insert onto the midline raphe
innervated by CN X

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34
Q

What are the properties of the longitudinal muscles within the pharynx?

A

form the inner layer, they are supplies by CN X and IX
they are attached to the larynx and contract to shorten the pharynx
they raise the larynx to close over the laryngeal inlet

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35
Q

where does the oesophagus begin?

A

at the edge of the cricopharygeus muscle (vertebral level C6)

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36
Q

What is the oesophageal plexus?

A

it runs on the surface to supply smooth muscle within its walls (distally)

  • contains parasympathetic nerve fibres (vagal trunks) and sympathetic nerve fibres
  • these fibres are responsible for influencing the ENS to speed up (P) or slow down (S) peristalsis
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37
Q

What is the lower oesophageal sphincter?

A

a physiological sphincter which helps to reduce the occurrence of reflux
the presence of a hiatus hernia will reduce its effectiveness - ca lead to reflux
immediately superior to the gastro-oesophageal junction
there is an abrupt change in type of mucosa lining the wall

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38
Q

What factors are involved in producing the sphincter effect in the lower oesophageal sphincter?

A

Contraction of diaphragm
Intrabdominal pressure slightly higher than intragastric pressure
Oblique angle at which oesophagus enters the cardia of stomach

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39
Q

Where in the body does the stomach lie?

A

mainly in the left hypochondrium, epigastric and umbilical regions when the patient is supine
- a J shaped organ

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40
Q

What organs are within the foregut?

A

Oesophagus to mid-duodenum

Liver, gallbladder, spleen and 1/2 of pancreas

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41
Q

What are the organs within the mid gut?

A

Mid-duodenum to proximal 2/3rd of transverse colon

1/2 of pancreas

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42
Q

What organs are in the hind gut?

A

Distal 1/3rd of the transverse colon to proximal 1/2 of the anal canal

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43
Q

What is mainly common to all organs in a gut region?

A

Arterial blood from common artery
Venous drainage from common vein
Lymphatic drainage via shared route
Nerve supply via common route

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44
Q

What are the 9 regions of the anterior abdomen?

A 
Right/Left Hypochondrium
Epigastric
Right/Left Lumbar (flank)
Umbilical
Right/Left Inguinal (iliac fossa)
Pubic (suprapubic) (hypogastric)
The divisions are along the mid-clavicular, subcostal and trans-tubercular planes
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45
Q

What are the 4 quadrants on the back?

A

Right/Left Upper Quadrants
Right/Left Lower Quadrants
The divisions are along the median and trans-umbilical planes

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46
Q

What about the paritoneum allows the intestines to be so mobile?

A

The joining to the peritoneal wall by a mesentry

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47
Q

Where is the greater omentum?

A

It is a double layer (condensation of peritoneum) that comes down the front bends round the bottom and then travels up covering the abdominal cavity but particularly the intestines

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48
Q

Where will excess fluid in the peritoneum gather when someone is standing up?

A

In the pouches

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49
Q

What is the lower pouch within the female?

A

the pouch of douglas (recto-uterine pouch)

the other pouch is the vesico-uterine pouch

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50
Q

What is the pouch called in males?

A

rectovesical pouch

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51
Q

What does abdominal pain which comes and goes indicate?

A

intestinal pain linked to peristalsis

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52
Q

Where does foregut organ pain tend to be felt?

A

the epigastric region

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53
Q

Where does mid gut organ pain tend to be felt?

A

the umbilical region

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54
Q

Where does hindgut organ pain tend to be felt?

A

the pubic region

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55
Q

What makes up the large intestine from proximal to distal?

A 
The colon
- Caecum
- Appendix
- Ascending colon
- Transverse colon
- Descending colon
- Sigmoid colon
The rectum
The anal canal
The anus
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56
Q

What is the peritoneum?

A

a thin, transparent, semi-permeable, serous membrane which lines the walls of the abdominopelvic cavity and organs.
It is a continuous layer of membrane and where it is in contact which the organs it is visceral and where it is in contact with the soma it is parietal, the nerve supply differs depending on where it is in contact with
The peritoneum secretes small amounts of lubricating fluid and creates the peritoneal cavity between the visceral and parietal layers

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57
Q

What are the 3 organ classifications linked to their relationship with the peritoneum?

A

intraperitoneal
retroperitoneal
with a mesentery

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58
Q

What is the relationship between inraperitoneal organs and the peritoneal e.g liver?

A

Almost completely covered in visceral peritoneum

Minimally mobile

59
Q

What is the relationship between retroperitoneal organs and the peritoneal?

A

Only has visceral peritoneum on its anterior surface

Located in the retroperitoneum

60
Q

What is the relationship between organs with a mesentery and the peritoneal?

A

Covered in visceral peritoneum
Visceral peritoneum wraps behind the organ to form a double layer – mesentery
Mesentery suspends the organ from the posterior abdominal wall – very mobile

61
Q

What do the omenta do?

A

they provide the peritoneal into the greater and lesser sac

  • the lesser sac is smaller
  • omental foramen allow the 2 sacs to communicate
  • ‘portal triad’ lies in the free edge of the lesser omentum
62
Q

How are the pouches formed?

A

The inferior aspect of the peritoneum drapes over the superior aspects of the pelvic organs - these are part of the greater sac

63
Q

What is ascites?

A

When the patient has ascites - excess fluid in the peritoneal cavity
- this fluid can be drained by paracentesis - abdominocentesis

64
Q

What happens during paracentesis?

A

the needle must be places lateral to the rectus sheath to avoid the inferior epigastric artery
(It ascends in anterior abdominal wall & is deep to rectus abdominis. It originates from the external iliac which is just medial to the deep inguinal ring)
- ultrasound guidance should be used if available

65
Q

What are the 4 important questions for abdominal pain?

A

Location? - What is the relevant anatomy or organs which refer there? and is the pain localised as visceral pain is hard to localise, somatic pain is easier to localise
Character? - Visceral pain, from an organ, tends to be dull, achy and nauseating
Somatic pain, from the body wall, tends to be sharp and stabbing
Timing? - constant or intermittent
Pain referral pattern? - does it follow the classical distribution for a particular organ

66
Q

What nerves supply the organs within the abdominal cavity including rhe visceral peritoneum?

A 
Visceral afferents (sensory nerves)
The autonomic motor nerves
Parasympathetic (speed up peristalsis)
Sympathetic (slow down peristalsis)
Can influence the enteric nervous system
The enteric nervous system – completely specific to the digestive system
67
Q

What nerves supply the body wall of the peritoneum - abdominal wall of the cavity?

A
  • nerves come from the skin through the peritoneal cavity
  • somatic sensory nerves
  • somatic motor nerves
  • sympathetic nerve fibres
68
Q

Hoe do the sympathetic nerve fibres travel from the CNS to the abdominal organs?

A
  • leave spinal chord at T5 and L2
  • enter the bilateral sympathetic chains but don’t synapse
  • they leave the sympathetic chains within the abdominopelvic sphlanchnic nerves
  • they synapse at the prevertebral ganglia, located anterior to the aorta at the exit points of the major branches of the abdominal aorta
  • Postsynaptic sympathetic nerve fibres pass from the prevertebral ganglia (celiac, superior mesenteric etc) onto the surface of the arterial branches leaving the abdominal aorta
  • are part of the periarterial (surrounding artery) plexuses with other nerve fibres, parasympathetic and visceral afferent as they “hitch a ride” with the arteries, and their branches, towards (or away from if sensory) the smooth muscle and glands of the organs
69
Q

How do sympathetic fibres travel from the CNS to the adrenal gland?

A
  • it is an exception to the normal pattern
  • the sympathetic fibres for the adrenal gland leave the spinal cord at (T10 -L1)
  • enter the abdominopelvic splanchnic nerves
  • don’t synapse at prevertebral ganglia
  • carried with periarterial plexuses to the adrenal gland
  • synapse directly onto cells
70
Q

How do parasympathetic nerve fibres get from the CNS to the abdominal organs?

A

Vagus nerve (CNX)
- the presynaptic fibres enter the abdominal cavity on the oesophageal surface, they then travel into the periarterial plexuses at the abdominal aorta, these are carried to the organ walls where they synapse in ganglia. This parasympathetic supply goes along the GI tract up until the distal end of the transverse colon
Pelvic Splanchnic Nerves (S2,3,4) - Presynaptic parasympathetic nerve fibres
supply smooth muscle/glands of the descending colon to anal canal

71
Q

How do most of the visceral afferent nerve fibres travel from the organs to the CNS?

A

pain fibres from the vast majority of the abdominal organs run alongside sympathetic fibres back to the spinal cord
the pain from these organs tends to be perceived to be in the dermatomes at the level they enter the spinal cord - referred pain

72
Q

Where do the visceral afferent nerve fibres from the foregut enter the spinal cord?

A

T6-T9

73
Q

Where do the visceral afferent nerve fibres from the midgut enter the spinal cord?

A

T8-T12

74
Q

Where do the visceral afferent nerve fibres from the hindgut enter the spinal cord?

A

T10-L2

75
Q

What is the clasical presentation of appendicitis and why does it present this way?

A

initially felt as a dull, aching pain, in the umbilical region but then becomes a sharper pain at a point in the right iliac fossa
Organ pain transfers to body wall pain because it becomes inflamed and so starts to rub against the peritoneum and cause somatic pain

76
Q

What nerves convey the somatic motor, somatic sensory and sympathetic nerve fibres supplying the structures of the abdominal part of the body wall?

A
  • The thoracoabdominal nerves: 7th-11th intercostal nerves Travel anteriorly, then leave the intercostal spaces, travel in the plane between the internal oblique and transversus abdominis, as thoracoabdominal nerves
  • The subcostal nerve (T12 anterior ramus)
  • The iliohypogastric nerve (half of L1 anterior ramus)
  • The ilioinguinal nerve (other half of L1 anterior ramus)
77
Q

3 functions of the large intestine

A

Defence - commensal bacteria
Absorption - H2O & electrolytes
Excretion - of formed stool

78
Q

How many paracolic gutters are there?

A

2 left and right

79
Q

What are the paracolic gutters?

A

They lie between the lateral edge of the ascending and descending colon and the abdominal wall - a part of the greater sac of peritoneal cavity
these are also potential sites of pus collection

80
Q

Where does the splenic flexure lie in relation to the hepatic flexure?

A

it is more superior

81
Q

What are the tenaie coli?

A

3 distinct longitudinal bands of thickened smooth muscle, running from caecum to distal end of sigmoid colon

82
Q

what is the anatomical relationship between the caecum and appendix?

A

Both lie in the right iliac fossa

appendix is normally reterocaecal but can be variable

83
Q

Where is the appendiceal orifice?

A

on posteromedial wall of caecum
corresponds to McBurney’s point on the anterior abdominal wall 1/3 of the way between right ASIS to umbilicus
maximum tenderness in case of appendicitis (in theory)

84
Q

Where is the sigmoid colon found?

A

in the left iliac fossa

85
Q

Describe the mobility of the sigmoid colon?

A

considerable degree of movement because of its long mesentery
negative side: sigmoid colon at risk of twisting around itself
sigmoid volvulus
clinically results in bowel obstruction
bowel at risk of infarction if left untreated

86
Q

Where is the abdominal aorta found?

A

midline, retroperitoneal structure

lies anterior to vertebral bodies and to left of IVC

87
Q

What are the 3 midline branches of the aorta?

A

Celiac trunk - foregut
superior mesenteric artery - midgut
inferior mesenteric artery - hindgut

88
Q

What do the lateral branches of the abdominal artery supply?

A 
kidneys/adrenal glands
Gonads (ovaries / testes)
body wall (posterolateral)
89
Q

what arteries does the abdominal artery bifurcate into?

A

the common iliacs which then bifurcate again to the internal and external iliacs

90
Q

What is the marginal artery of Drummond?

A

the main arterial anastomoses between the superior and inferior mesenteric arteries
these anastomoses have the potential to help prevent intestinal ischemia by providing an alternative route for blood

91
Q

What is the blood supply to the rectum and the anal canal?

A

the inferior mesenteric artery supplies the hindgut so the proximal half of the anal canal to the pectinate line
The rest of the anal canal and rectum is supplies by the internal iliac artery although there is anastomoses between these vessels

92
Q

What can cause haematemesis?

A
  • a peptic ulcer in the duodenal/ stomach

- bleeding of oesophageal varices

93
Q

How do peptic ulcers cause haematemesis?

A

the peptic ulcer erodes through the mucosa filling the duodenum/ stomach with blood

94
Q

How do oesophaeal varices cause haematemesis?

A

they are abnormal dilated veins which are thin walled, therefore have potential to rupture
filling oesophagus with blood
formation often due to pathology affecting the portal venous system

95
Q

Where does the inferior vena cava (reteroperitoneal) drain from and to?

A

drains cleaned blood from the hepatic veins into the right atrium

96
Q

Where does the hepatic portal vein drain from and to?

A

drains blood from foregut, midgut and hindgut structures to the liver for first pass metabolism

97
Q

Where does the splenic vein drain from and to?

A

drains blood form foregut structures to hepatic portal vein

98
Q

Where does the superior mesenteric vein drain from and to?

A

drains blood from midgut structures to hepatic portal vein

99
Q

Where does the inferior mesenteric vein drain from and to?

A

drains blood from hindgut structures to splenic vein

100
Q

Describe the 3 important venous anastomosis between the systemic and portal venous systems

A

the presence of small collateral veins means blood can flow both ways
either into the systemic or portal venous system
there are no valves in these veins
normally there is very little blood flow within these collateral veins

101
Q

Where are the 3 main portal-systemic anastomoses

A
  • at the distal end of the oesophagus inferior part drains to the hepatic portal vein and superior part to the azygous vein
  • skin around umbilicus: ligamentum teres remains closed throughout adult life and blood flows from the skin around the umbilicus via inferior epigastric veins to the IVC
  • rectum / anal canal: rectum and superior anal canal drains to inferior mesenteric vein most inferior part of GI tract drains to the internal iliac veins
102
Q

What is portal hypertension?

A

clinical term given to increased blood pressure within the portal veins can occur as a result of liver pathology, e.g. cirrhosis

103
Q

What is the impact of portal hypertension?

A

blood will be diverted through the collateral veins back to the systemic venous system
These collateral veins consequently have a much larger volume of blood through them than they are used to
so dilate, becoming varicose

104
Q

What is the role of the rectum in the process of faecal excretion?

A

it i the holding area to store faeces until it is appropriate to defecate

105
Q

What is the role of the normal visceral afferent nerve fibres in the process of faecal excretion?

A

To sense fullness of the rectum

106
Q

How is it decided whether it is appropriate to defecate?

A

through the normal cerebral function causing the muscle sphincters to contract to prevent or relax to allow defecation

107
Q

What can affect faecal continence?

A

neurological pathology
medications
the natural age-related degeneration of nerve innervation of muscle - affected by consistency of stool

108
Q

What is the pelvic cavity?

A

The cavity contained within the bony pelvis which is continuous with the abdominal cavity
It lies between the pelvic inlet and the pelvic floor and contains pelvic organs, supporting tissues and the rectum

109
Q

What passes through the pelvic floor?

A

the distal parts of the renal, reproductive tracts and the rectum/anal canal

110
Q

Where does the sigmoid colon become the rectum

A

at the rectosigmoid junction anterior to S3

111
Q

Where does the rectum become the anal canal?

A

Anterior to the tip of the coccyx just before passing through the levator ani muscle

112
Q

What is the anus?

A

The distal end of the anal canal and is the orifice faeces passes through

113
Q

Where is the rectal ampulla?

A

Directly superior to the levator ani muscle, its walls are able to relax in order to accommodate faecal material

114
Q

What covers the superior rectum?

A

the peritoneum

115
Q

Where is the prostate gland in relation to the rectum?

A

anterior to the inferior rectum

116
Q

Where is the vagina and cervix in relation to the rectum?

A

it is anterior to the inferior/ middle rectum

117
Q

Where is the rectouterine/ rectovesical pouch in relation to the rectum?

A

anterior to the superior rectum

118
Q

What are the levator ani muscles?

A

they form the pelvic diaphragm along with the fascial coverings. The levator ani muscles are made up of a number of smaller muscles
Skeletal muscle forms the pelvic floor/ perineum roof

119
Q

What is the function of the levator ani muscles

A
  • continual support for the pelvic organs - tonically contracted most of the time
  • Reflexively contracts further during increase in intra-abdominal pressure, e.g. coughing, sneezing
  • The muscle must relax to allow defecation (and urination) to occur
  • Supplied by the “nerve to levator ani”: (a branch of the sacral plexus) & pudendal (S2, 3, 4)
120
Q

What is the puborectalis?

A

Part of the levator ani muscle, important for maintenance of faecal continence as when it contracts the anorectal angle is decreased- like a sphincter
skeletal muscle - when the rectal ampulla is full of faeces and relaxed the puborectalis maintains faecal continence

121
Q

What are the anal sphincters?

A

there 2 anal sphincters the internal smooth muscle and external skeletal muscle

122
Q

What are the properties of the internal anal sphincter?

A

superior two thirds of anal canal
contraction is stimulated by sympathetic nerves
contraction is inhibited by parasympathetic nerves
contracted all the time, relaxes reflexively in response to distension (filling) of the rectal ampulla

123
Q

What are the properties of the external anal sphincter?

A

inferior two thirds of anal canal (superior part of the sphincter is continuous with the puborectalis muscle)
contraction is stimulated by the pudendal nerve
voluntarily contracted (along with puborectalis muscle) in response to rectal ampulla distension and internal sphincter relaxation

124
Q

What nerves supply different parts of the pelvis/ perineum?

A

If in the pelvis sympathetic, parasympathetic and visceral afferent nerves
If in the perineum somatic motor or somatic sensory nerves

125
Q

What nerves significant to the rectum/ anal canal travel from T12-L2?

A

Sympathetic fibres which synapse at the inferior mesenteric ganglia and then reach the rectum via periarterial plexuses around the branches of the IMA
they stimulate contraction of the internal anal sphincter and inhibit peristalsis

126
Q

What nerves significant to the rectum/ anal canal travel from S2-S4?

A

somatic motor from pudendal nerve (S2-S4) and nerve to levator ani (S3,S4): - contraction of external anal sphincter and puborectalis
visceral afferents back to S2-S4: run with parasympathetics - sense stretch, ischaemia etc.
parasympathetic fibres from S2-S4: via pelvic splanchnic nerves, synapse in walls of rectum - inhibit internal anal sphincter & stimulate peristalsis

127
Q

Describe the path of the pudendal nerve?

A

a branch of sacral plexus, comes from S2, S3, S4 anterior rami and supplies the external anal sphincer and exits the pelvis at the greater sciatic foramen
It then enters the perineum quickly throught the lesser sciatic foramen where its branches supply structures of the perineum

128
Q

How can labour result in faecal incontinence?

A

the branches of the pudendal nerve could be stretched

fibres of the puborectalis or external anal sphincter muscle could be torn resulting in weakening of the muscle

129
Q

What is the pectinate line?

A

The junction of the anal canal which marks the part formed by the GI tract (endoderm) and the part formed by the skin (ectoderm)

130
Q

What is the significance of the pectinate line?

A

The arterial supply, venous drainage, lymphatic drainage and nerve supply vary depending on the side of the line
superior = visceral (hindgut)
inferior = parietal (body wall)

131
Q

What are the supplies of the anal canal above the pectinate line?

A

Nerve supply - autonomic
Arterial supply - from inferior mesenteric artery
Venous - to portal venous system
Lymphatic - inferior mesenteric nodes (internal iliac nodes)

132
Q

What are the supplies of the anal canal below the pectinate line?

A

Nerve supply - somatic & pudendal
Arterial supply - from internal iliac artery
Venous - to systemic venous system
Lymphatic - superficial inguinal nodes

133
Q

What are the main groups of lymph nodes which drain the pelvic organs?

A 
internal iliac (draining inferior pelvic structures)
external iliac (draining lower limb, and more superior pelvic structures)
common iliac (drain the lymph from the external and internal iliac nodes)
lymph draining through the common iliac nodes then drains to the lumbar nodes
134
Q

What is the venous drainage of the rectum and anal canal?

A

above the pectinate line drains to the superior rectal vein then the inferior mesenteric vein
below the pectinate line drains to the middle rectal vein the internal iliac vein and then the inferior rectal vein

135
Q

What are rectal varices?

A

They are formed s a result of portal hypertension causing dilatation of the collateral veins and between the portal & systemic venous system

136
Q

What are rectal haemorrhoids?

A

prolapses of the rectal venous plexuses, unrelated to portal hypertension can be caused by raised pressure e.g. pregnancy & chronic constipation

137
Q

What are the ischioanal fossae?

A

(right and left) lie on either side of the anal canal
filled with fat & loose connective tissue
fossae communicate posteriorly with each other
infection of them calles an ischioanal abcess

138
Q

What are the 5 parts of the pancreas?

A
  • uncinate process
  • head
  • neck
  • body
  • tail
139
Q

What are the 2 functions of the panccreas and what cells are involved in each function?

A

exocrine function - acinar cells which secrete pancreatic enzymes
endocrine function - islets of Langerhans secrete hormones into the blood

140
Q

What regulates the secretions of pancreatic fluid?

A

vagus nerve and gastrin levels

141
Q

What are the enzymes within the pancreatic fluid that were secreted by the acinar cells?

A

protease - turns polypeptides to peptides
pancreatic lipase - triglycerides to fatty acids & monoglycerides
pancreatic amylase - carbohydrates to disaccharides and monosaccharides

142
Q

What is secreted by the epithelial cells lining the ducts into the pancreatic fluid?

A

bicarbonate - base to neutralise the acidic gastric juice

water

143
Q

What quantity of pancreatic fluid is secreted everyday?

A

1 litre

Gastrointestinal (12 decks)

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