Week 1 Part 2 Flashcards
What nerve supplies the muscles of mastication?
Trigeminal
V
(specifically madibular division of trigeminal nerve, V3)
What muscle(s) are responsible for closing the mouth?
3 muscles
Temporalis
Masseter
Medial pterygoid
What muscle(s) aer responsible for opening the mouth?
1 muscle
Lateral peterygoid
What nerve innervates the posterior 1/3 of the tongue?
Glossopharyngeal (IX)
What nerve innervates the anterior 2/3 of the tongue?
Hypoglossal (CNVII)
Where are the foliate papillae?
Sides of the tongue
Where are the vallate papillae?
The massive taste buds at the back of the mouth
What is the name of the taste buds in the centre of the tongue?
Fungiform papillae
What is the name for the taste buds on the end of the tongue and what do they do?
Filiform papillae
Touch and temperature
Where does the facial nerve pass through in the skull?
Stylomastoid foramen
The superior part of the mouth is innervated by which cranial nerve?
The inferior part of the mouth…?
V2 (superior)
V3 (inferior)
Which foramen do the sensor fibres of CN V2 travel through?
Foramen rotundum
Which foramen do the glossopharyngeal nerves (IX) pass through?
Jugular foramen
What nerve innervates the palatoglossus?
Vagus (X)
What nerve innervates the muscles of the tongue?
Hypoglossal (XII)
What nerve innervates the muscles of the pharynx?
Vagus (X)
What are the muscles of the tongue?
Extrinsic - Palatoglossus + Styloglossus
Intrinsic - Genioglossus + Hypoglossus
Where is the vagus nerve inserted into on the pharynx?
Midline raphe
Are the longitudinal muscles of the pharynx the inner layer or the outer layer?
Inner
What nerves innervate the longitudinal muscles of the pharynx?
CN X and IX
What is the name of the circular muscle around the mouth/libs?
Obicularis oris
What muscles shorten the pharynx and raise the larynx to assist with swallowing?
Longitudinal muscles of the pharynx
Are the muscles involved in swallowing skeletal or smooth?
Skeletal
Where does the oesophagus begin?
Inferior edge of cricopharyngeus muscle
C6
What is the name of the upper oesophageal sphincter?
Cricopharyngeus
What is the line that signifies the end of oesophageal mucosa and the beginning of the stomach mucosa?
Z-line
What is steatorrhoea?
Fat in the faeces
What is Hartnup disease?
Autosomal recessive metabolic disorder
Affects the absorption of nonpolar amino acids
What is cystinuria?
Inherited autosmoal recessive disease
High concentrations of amino acid cystine in the urine
Leads to the formation of cytstine stones in the kidneys, ureter and bladder
What is luminal digestion mediated by?
Pancreatic enzymes secreted into the duodenum
What is membrane digestion mediated by?
Enzymes situated at the brush border of epithelial cells
What is assimilation?
Digestion and absorption
What does sucrose need to be broken down into in order to be absorbed?
Glucose and fructose
What alpha linkages does amylopectin have?
Alpha-1,6 and alpha-1,4
What must dietary carbohydrate be converted to in order to be absorbed by the intestine?
Monosaccharides
What does amylase do?
Converts starch to oligosaccharides
What do lactase and maltase do?
Convert oligosaccharides to monosaccharides
What does amylase break down?
Linear, internal alpha-1,4 linkages
How are glucose and galactose absorbed?
Secondary active transport mediated by SGLT1
How is fructose absorbed in the gut?
Facilitated diffusion mediated by GLUT5
How do monosaccharides exit the cell?
Facilitated diffusion medited by GLUT2
How does SGLT1 work in very basic terms?
2Na+ binds to the transporter which increases the transporter’s affinity for glucose. Glucose binds, the gate opens and botht he 2Na+ and the glucose enters into the cell membrane
What is pepsin and what does it do?
Endopeptidase
Cleaves proteins into peptides
What is trypsin?
Endopeptidase
What is elastase?
Endopeptidase
How are amino acids transported into enterocytes?
5 Na+ co-transporters - secondary active transport - neutral amino acids
2 Na independant - cationic amino acids
Di-, tri- and tetra-peptides are transported via what?
H+ dependant mechanism at brush border
What further hydrolyses olgiopeptides to amino acids?
Peptidases at the brush border
How do amino acids exit the enterocyte?
Na+ independent mechanisms
What causes night-blindness?
Vitamin A deficiency
What is haemochromatosis?
Build up of iron in the blood
What causes scurvy?
Vitamin C deficiency
Are lipids soluble in water?
Some are insoluble and some are poorly soluble
What is the main digestive enzyme in the duodenum?
Pancreatic lipase
What do bile salts do?
Act as detergents to emulsify large lipid droplets to small droplets
Are bile salts hydrophilic, hydrophobic or both?
Amphipathic
What happens if bile salts are not secreted?
Lipid malabsorption leading to steatorrhoea
Secondary vitamin deficiency
What does colipase do?
Binds to lipase and bile salt to allow lipase to work
What are triglycerides digested into?
2-monoglyceride and two free fatty acids
Where do short chain and medium chain fatty acids go after they’ve diffused into the enterocyte?
Exit through the basolateral membrane and enter the villus capillaries
What happens to long chain fatty acids and monoglycerides in the intestines?
Resynthesized to triglycerides in the endoplasmic reticulum and are subsequently incorporated into chylomicrons
How are chylomicrons formed?
Monoglycerides and fatty acids are turned into triglycerides
Triglycerides enter the endoplasmic reticulum and are synthesised into cholesterol esters
Nascent chylomicron is formed and binds with an apoliopoprotein to form a Chylomicron
What is the absorption of calcium regulated by?
calcitriol and parathyroid hormone
How is calcium absorbed in the duodenum and upper jejunum?
Active transport
How is calcium absorbed in the small intestine?
Passive transport
What is one of the major controls on iron absorption?
Ferroportin
Why is the absorption of vitamin B12 a ‘special case’?
It is present in minute amounts in the diet so efficient and selective absorption is required
What organs are included in the foregut?
Oesophagus to mid duodenum
Liver
Gall bladder
Spleen
1/2 of the pancrease
What structures are included in the midgut?
Mid duodenum to proximal 2/3rds of the transverse colon
1/2 pancreas
What is included in the hindgut?
Distal 1/3rd of transverse colon to proximal 1/2 of anal canal
Where is the right hypochondrium?
Right upper region
Where is the left lumbar?
Middle left region
What type of peritoneum is in touch with the organ?
Visceral
Name 5 retro-peritoneal organs
Kidneys
Adrenal gland
Pancreas
Ascending colon
Descending colon
What is the name of the mesentery that is attached to the appendix?
Mesoappendix
What is the name of the space behind the liver and infront of the spine called?
Lesser sac
What is the name of the space infront and in between the intestines called?
Greater sac
How many layers is the greater omentum made up of?
4
How many layers is the lesser omentum made up of?
2
Which omentum has a free edge?
Lesser omentum
What is the hole called that allows the communication of the greater and lesser sacs?
Omental foramen (foramen of Winslow)
What is the name of the one pouch formed between the bladder and the rectum in a male called?
The rectovesical pouch
What are the names of the two pouches formed between the bladder and the uterus and the uterus and the rectum called?
Bladder + uterus - Vesico-uterine pouch
Uterus + Rectum - Recto-uterine pouch
What is the procedure called that drains asctitc fluid called?
Paracentesis
What does visceral pain feel like?
Dull, achy and nauseating
What does pain coming from the body wall (somatic) pain feel like?
Sharp and stabbing
What type of nerves are visceral afferents?
Sensory nerves
The nerves that supply the abdominal organs leave the sympathetic chain at what levels?
T5 - L2
Where do the sympathetic nerves that supply the abdominal organs synapse?
At the prevertebral ganglia anterior to the aorta
Where is the periarterial plexus located?
On top of the abdominal aorta?
What do the nerves on top of the abdominal aorta make up?
The periarterial plexus
Where do the sympathetic nerves for the adrenal gland leave the spinal chord?
T10 - L1
THEY SYNAPSE DIRECTLY ONTO CELLS
What are the pelvic splanchnic nerves?
S2, 3 and 4
Where do the visceral afferent nerve fibres for the foregut, enter the spinal chord?
T6-T9
Where do the visceral afferent nerve fibres for the midgut enter the spinal chord?
T8 - T12
Where do the visceral afferent nerve fibres for the hindgut enter the spinal chord?
T10 - L2
