Metabolism Flashcards
Where does the parotid gland open out?
Opposite the second upper molar
Where does the submandibular gland open out?
Either side of the frenulum
Where does the sublingual gland open out?
Plica sublingualis - fold between tongue and body of the mandible
Nerve supply to the parotid gland
Via auriculo-temporal nerve
Sensory fibres from V3
Parasympathetic fibres from the lesser petrosal nerve from CN IX
Nerve supply to the submandibular and sublingual glands
Chorda tympani
Derivatives of body and root of the tongue
Body = ectoderm Root = endoderm
4 extrinsic muscles of the tongue and their innervation
Styloglossus - CN XII - to styloid process
Genioglossus - CN XII - to mandible
Palatoglossus - CN X - to palate
Hypoglossus - CN XII - to hyoid bone
Nerve supply to the anterior 2/3 of the tongue
General sensory = V3
Special sensory = CN VII
Nerve supply to posterior 1/3 of the tongue
General and special sensory = Cn IX
Patch at the root = internal laryngeal CN X
Pharyngeal constrictor muscles
Superior - from medial pterygoid plate
Middle - from angle between hyoid horns
Inferior - from lateral thyroid cartilage
Muscles of mastication and actions
Temporalis - closes mouth
Masseter - closes mouth
Medial pterygoid - closes mouth
Lateral pterygoid - opens mouth
Innervation of muscles of mastication
V3
Extent of oesophagus
C6–>T10
What muscle is found around the UOS
Cricopharyngeal
Sites of oesophageal constrictions
In the pharynx
Behind aortic arch
Diaphragmatic
3 layers of stomach muscle
Inner oblique
Middle circular
Outer longitudinal
4 parts of duodenum
Superior
Descending
Horizontal
Ascending
Jejunum vs ileum
Jejunum darker Jejunum more vascular Jejunum more folds Jejunum thicker walls Jejunum less fat
Quantity of jejunum vs iluem
Jejunum = 2/5 of gut Ileum = 3/5
Where is the bare area of the liver?
Superior and posterior surfaces
Arterial arcades in jejunum vs iluem
Longer but fewer in jejunum
More but shorter in ileum
Portal venous system
Splenic and inferior mesenteric veins join
Then join superior mesenteric vein
Forms hepatic portal vein
Coeliac trunk branches
Left gastric
Splenic
Common hepatic
Splenic artery branches
Left gastroepiploic
Short gastrics
Common hepatic artery branches
Hepatic artery proper –> left and right hepatic, cystic, right gastric
Gastroduodenal –> right gastroepiploic, superior pancreaticoduodenal
Superior mesenteric artery branches
Jejunal and ileal
Iliocolic
Right colic
Middle colic
Inferior mesenteric artery branches
Left colic
Sigmoidal
Superior rectal
Falciform ligament
Anterior abdominal wall –> liver
Lesser omentum
Liver –> lesser curvature of the stomach
Greater omentum
Greater curvature of the stomach –> transverse colon
Transverse mesocolon
Transverse colon –> posterior body wall
Mesentery
Small intestine –> posterior body wall
Immune systems in the gut
MALT
Secretory IgA
Gut layers
Mucosa
Submucosa
Muscularis propria
Adventitia
Oesophageal epithelium
Stratified squamous
What is secreted by the cardia of the stomach?
Mainly mucous from mucous neck cells
What is secreted by the fundus of the stomach?
Mucous from mucous neck cells
HCL and intrinsic factor from parietal cells
Pepsin from chief cells
Gut hormones from endocrine cells
What is secreted by the pylorus of the stomach?
Mainly mucous from mucous neck cells
Gut hormones from endocrine cells
Cells of intestinal crypts
Enterocyte - secretion of watery intestinal juice
Endocrine cell - regulation of gut function
Stem cell - regeneration of epithelium
Paneth cell - antimicrobial agent release such as lysozyme
Where are Peyer’s patches found?
Lamina propria of the ileum
What are taenia coli?
Bands of longitudinal muscle in the colon
Where are Brunner’s glands found?
Submucosa of the duodenum
Brunner’s gland function
Alkaline mucous secretion for neutralisation of acidic chyme
Which enzyme has a calmodulin subunit that is activated during enzyme and what is its function?
Phosphorylase kinase A
Phosphorylated glycogen phosphatase
Activates glycogen breakdown
What does calcium activate during exercise?
PDC phosphatase to activate PDC to promote entry in TCA cycle
Dehydrogenase enzymes of the TCA cycle
What does AMP do in exercise?
Increases GLUT4 channels Enzymes at the start of glycolysis Glycogen phosphorylase AMPK which turns on PFK2 Inactivates ACC to prevent malonyl CoA formation which would inhibit fatty acid breakdown for energy
What is hormone sensitive lipase controlled by?
Promoted by glucagon and adrenaline
Inhibited by insulin
Process of fatty acid breakdown
Activation by ATP to form fatty acyl CoA
Transport into mitochondria via carnitine shuttle
Beta oxidation to produce acetyl CoA, NADH and FADH2
How is CPT1 (carnitine shuttle) controlled?
Promoted by cAMP and glucagon
Inhibited by malonyl CoA
Lipogenesis steps
Formation of malonyl CoA by acetyl CoA carboxylase
Fatty acid synthetase adding 2 carbons at a time
Ketone body formation
acetyl CoA –> acetoacetyl CoA –> HMG CoA –> acetoacetate
Effect on insulin on ketone body production
Insulin inhibits ketone body production by inhibiting HSL and CPTI
Ketoacidosis common in diabetics
What enzyme is used to overcome glucokinase?
Glucose-6-phosphatase
What enzyme is used to overcome PFK?
Fructuse-1,6-phosphatase
What enzyme is used to overcome pyruvate kinase?
Pyruvate carboxylase
Malate dehydrogenase
PEP carboxykinase
Where does glycerol enter respiration?
Dihydroxyacetone phosphate in glycolysis
Where does glutamine/glutamate enter the TCA cycle?
As a-ketoglutarate