Answered.
where are long reflexes integrated? correct answers CNS - sensory info from eyes, ears and nose
go to CNS (brain) and activates GI tract
- includes cephalic reflexes - sight, smell, thought of food
where are short reflexes integrated? correct answers in the gut - enteric nervous system
- neurons in submucosal plexus receive signals from lumen, regulate secretion
- neuros in myenteric plexus regulate motility
long reflex pathway correct answers - sensory info comes in from eyes, nose, etc
- integrated in brain
- travels mostly via sympathetic (vagus nerve) increasing rest and digest
- communicates with neurons
- secretion + motility
- acts on smooth muscle - motility
end game: increased secretion increased motility
*this all happens before you even eat anything*
short reflex pathway correct answers - need something in GI tract (stretching, osmolarity, acid
secretion - cells get detected)
- neurons in GI tract communicate with neural networks
- increase section + motility
what are parallels between enteric and CNS? correct answers - both have intrinsic neurons
- release more than 30 different neurotransmitters to make neural networks work
- diffusion barrier similar to blood-brain barrier
, - an integrating centre - gut regulation can be regulated without input from CNS
how can reflexes involving gut peptides act? correct answers paracrine (locally)
- diffuse to target cell - produced within lamina propria
endocrine
- gut hormones that travel via blood
what did Pavlov believe about pancreatic secretion? correct answers he thought there are
ascending afferent from duodenum that go up to brain and efferents that go down from brain to
tell pancreas to secrete
- controlled by vagus nerve
what did Bayliss and Starling discover? correct answers pancreatic secretions (bicarb and
enzymes) out the pancreatic duct occurs due to blood-borne signal: secretin (hormone)
what is secretin and what does it do? correct answers - a hormone that is released when chyme
arrives in the duodenum and is too acidic
- secretes Bicarbonate (HCO3-)
what is the gastrin family? correct answers - gastrin (targets stomach, intestine)
- CCK (accessory organs)
what is the secretin family? correct answers - secretin
- vasoactive intestinal peptide (VIP)
- gastric inhibitory peptide (GIP)
- glucagon-like peptide-1 (GLP-1)
both endocrine and exocrine targets