Case 1 Flashcards
European Convention on Human Rights Article 2
Right to life
European Convention on Human Rights Article 3
inhuman and degrading treatment
European Convention on Human Rights Article 8
right to respect for private and family life
True or False: Phospholipid bilayer is impermeable to ions and polar molecules
True
What provides permeability to ions and polar mols through phospholipid bilayer?
Membrane proteins like channels, pumps, and carriers
What regions form helical transmembrane domains?
hydrophobic
Which proteins within tight junctions form the closest connection between cells?
Claudins
Aquaporins are highly selective to water. Which aquaporin is important in salivary secretion?
Aquaporin 5
Describe the structure of K+ channels
4 subunits arranged around a central pore
Describe facilitated diffusion uniport
One molecule passing through channel at once in one direction
cotransporter symporter
2 molecules passing at once through channels in same direction
exchangers antiporter
2 molecules passing in opposite directions at once
Which type of solute carrier families do glucose transporters belong to?
SLC2
GLUT1 found in
Red cell, brain, kidney, placenta
GLUT 2 found in
Liver, intestine
GLUT3 found in
Astrocytes, neurones
GLUT 4 found in
Adipocytes, muscle
GLUT5 found in
Intestine
An important symporter in salivary glands
Na+, K+, 2Cl- cotransporter. Inward movement of Na+ drives uptake of Cl- against its gradient.
antiporter:
Na+, H+ exchanger,Opposite direction movement
Which ion gradient creates membrane potential
K+ gradient
Which subunits make up the Na+, K+ ATPase
Alpha and beta
Acinar cells of submandibular glands
Serous and mucous acinar cells
Acinar cells of parotid glands
Mainly serous acinar cells
Acinar cells of sublingual glands
Mainly mucous
Acinar cells of buccal glands
mucus
average daily secretion of saliva
1L
Saliva contains 2 main secretions
serous secretion - contains ptyalin (alpha-amylase) and Mucus secretion - contains mucin for lubricating and surface protective purposes
normal pH of saliva
6-7
Primary secretion of saliva by acinar cells
contain ptyalin or mucin. Secretion of Na+, Cl-, HCO3-, water added by osmosis. Isotonic, plasma-like secretion.”
Secondary secretion by salivary duct cells
reabsorption of NaCl from the duct, some secretion of potassium ions and bicarbonate ions into the duct. Duct cells have low water permeability, so final saliva = HYPOTONIC
what factors are contained within saliva to destroy bacteria
thiocyanate ions - bactericidal, lysosomes preolytic enzymes - aid thiocyanate ions and digest food particles.
which brain-stem nuclei control salivary glands
parasympathetic nervous signals form superior and inferior salivatory nuclei
Parasympathetic pathway of salivary secretion
ACh acts on the muscarinic receptors of the salivary glands. subsequent formation of inositol trisphosphate IP3 leads to increased Ca2+ concentrations within the cell. the second messenger significantly affects salivary volume secretion. Glandular secretion is sustained by acetylcholinesterases, which inhibit the breakdown of ACh.
sympathetic pathway of salivary secretion
Binding of the norepinephrine to α-adrenergic receptor results in formation of cAMP, which then leads to phosphorylation of various proteins and activation of different enzymes. Increases in cAMP result in increased salivary enzyme and mucus content.
organisation of GIT wall -inside to outside
Mucosa - epithelium, lamina propria, muscularis mucosae, Submucosa - Meissner’s submucosal plexus, Muscularis externa - Inner circular muscle, Auerbach’s Myenteric plexus, longitudinal muscle, serosa/adventitia
what does submucosal plexus control?
gastrointestinal secretion and local blood flow.
what does myenteric plexus control?
motility and secretes Vasoactive intestinal polypeptide VIP
what do the sensory neurons of enteric nervous system transmit?
they transmit the mechanical and chemical conditions of GIT
what do the motor neurons of enteric nervous system transmit?
control peristalsis and churning of intestinal contents.
peristalsis require an active ___
myenteric plexus
4 stages of swallowing or deglutition
- Cephalic stage - point where one is thinking about having a meal, 2. Oral stage (voluntary stage), 3. Pharyngeal stage - push food from pharynx to oesophagus, 4. Oesophageal stage - push food from pharynx to the stomach
key things happening during oral stage
chewing, salivation and tongue is retracted and push the bolus down into pharynx.
action of incisors
cutting food