Discuss, with examples, the feedforward and feedback control of the gastrointestinal tract by https://padlet.com/dilewis2/y5ga4zmdaai7 en-us 2020-01-24 08:47:10 UTC 2026-01-23 00:13:52 UTC hello@padlet.com EQ: Stomach feedforward vagal nerve input activate the gastric secretion feedback D-cell secrete somatostatin for the inhibition of gastric acid secretion from parietal cell https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439571507 2020-02-03 12:20:33 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439571507 Feedback controls refers to a mechanism which regulates a physiological parameter within given boundaries, e.g. negative feedback. https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439571714 In the GI tract this alters the degree of motility within the tract]]> 2020-02-03 12:21:12 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439571714 feedforward = the modification or control of a process using its anticipated results or effects https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439571783 2020-02-03 12:21:26 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439571783 https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439571995 A mechanism that prepares the body for something ]]> 2020-02-03 12:22:08 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439571995 https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572161 hormonal

]]> 2020-02-03 12:22:40 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572161 Colonic reflex - feedforward https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572240 2020-02-03 12:22:52 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572240 https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572340 Feedforward mechanism- prepare the GIT for digestion 
Feedback mechanism- stimulus modulates further release of hormones 
]]> 2020-02-03 12:23:13 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572340 nervous input and hormonal https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572617 2020-02-03 12:24:08 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572617 Paracrine https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572666 2020-02-03 12:24:17 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572666 Endocrine https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572674 2020-02-03 12:24:20 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572674 https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572688 hormonal


]]> 2020-02-03 12:24:21 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572688 humoral https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572726 2020-02-03 12:24:28 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572726 hormonal https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572745 2020-02-03 12:24:32 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572745 https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572766 Hormone release]]> 2020-02-03 12:24:35 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572766 hormonal https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572772 2020-02-03 12:24:35 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439572772 feed forward -ve neural https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439573015 2020-02-03 12:25:24 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439573015 Positive humoral feedforward control example would be the cephallic reflex. https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439573062

]]> 2020-02-03 12:25:30 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439573062 Feed forward +ve neural https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439573133 2020-02-03 12:25:41 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439573133 https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439573594 negative feedback of gastrin release- acid stimulates D cells which release somatostatin which inhibits G cells. reduces acid release when there is a decrease in stimuli]]> 2020-02-03 12:26:59 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439573594 feedback neural +ve https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439573706 2020-02-03 12:27:23 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439573706 gastrin release https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439573822

]]> 2020-02-03 12:27:43 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439573822 Somatostatin is the primary negative feedback signal https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574309 parietal cells stimulates D cells to release somatostatin. This directly and indirectly inhibits acid secretion by
inhibiting the secretion of H+ by parietal cells ;inhibiting the secretion of histamine by ECL cells, which stimulates parietal cells;
inhibiting the secretion of gastrin by G cells, which stimulates ECL cells and parietal cells.
This prevents damage to the GI tract caused by excess H+ ions, as well as indirectly inhibits pepsinogen secretion by chief cells.]]> 2020-02-03 12:29:06 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574309 https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574431 Feedback via the myenteric plexus- increased secretion ]]> 2020-02-03 12:29:21 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574431 feedforward positive: https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574591 sight/smell of food causes salivary glands to increase]]> 2020-02-03 12:29:50 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574591 feedforward, +ve humoral https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574655 Salivary response

]]> 2020-02-03 12:30:03 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574655 negative humoral feedback https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574742 enteroglycin decreases motility ]]> 2020-02-03 12:30:17 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574742 Distension of the gut: activates pressure receptors causing relaxation of the gut and inhibition of motility. A feed forward mechanism. neural https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574747 2020-02-03 12:30:19 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574747 https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574777 Negative humoral  feedback via somatostatin release  ]]> 2020-02-03 12:30:25 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574777 https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574780 partial cells - produce gastric acid when you see / smell food. = feedforward   (
positive neural)]]> 2020-02-03 12:30:25 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574780 negative neural feedback https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574989 ileogastric reflex = overdistension of the ileum causes inhibition of motility in the stomach]]> 2020-02-03 12:31:05 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439574989 Over distension of the ileum: inhibits motility in the stomach and decreases gastric emptying. Feed-back mechanism. Stops release of chyme and more distension. neural. https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575017 2020-02-03 12:31:09 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575017 https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575033 D cells = somatostatin = inhibits gastrin produciton. feedback, negative neural

]]> 2020-02-03 12:31:12 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575033 Vagal innervation of the upper 1/3 of the oesophagus, this is an example of a neural positive feedback mechanism as permits motility of the bolus via peristalsis contraction. https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575095 2020-02-03 12:31:19 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575095 https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575213 Ileo-gastric feedback -> distension in the small intestine will inhibit gastric motility (Neuronal –ve feedback) 

]]> 2020-02-03 12:31:42 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575213 positive humoral feedback https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575224 gastrin, secretin & CCK increase motility of the small intestine ]]> 2020-02-03 12:31:44 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575224 Feedforward positive https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575255 Nervous input to increase haustration and peristalsis in preparation for food moving through the intestine]]> 2020-02-03 12:31:50 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575255 negative feedforward : enteroglucagon https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575285 2020-02-03 12:31:56 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575285 Gastro ileal reflex: distension of stomach causes ileal relaxation. Feed forward. Prepares ileum for food entry. https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575313 2020-02-03 12:32:02 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575313 Negative feedback humoral mechanism when glucos or fat is detected in chyme. This leads to a release of enteroglucagon which decreases motility through the inhibition of peristalsis= increases absorbtion time. https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575686 2020-02-03 12:33:13 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575686 -ve feedback. neural. sight of food activates vagus which causes g cells to release gastrin. Gastrin causes parietal cells to release acid https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575780 2020-02-03 12:33:28 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439575780 Positive neural feedforward - gastrin increases acid secretion by parietal cells (vagus nerve) https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439576039 2020-02-03 12:34:09 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439576039 Neuronal feed forward -ve https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439576184 colono-colonic reflexes -> food in higher parts of the colon will cause relaxation in more distal parts of the colon ]]> 2020-02-03 12:34:34 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439576184 negative neural feedback https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439576289 organs outside of the GIT cause paralytic ileus ]]> 2020-02-03 12:34:56 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439576289 positive feedforward https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439576809 sight or smell of food activates gaphalic reflex- vagus nerve stimulated projects to G cells- neurostimulation of gastrin release- release of acid]]> 2020-02-03 12:36:26 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439576809 Neuronal feedforward + https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439577086 Gastro-colonic reflex 
distension of stomach will help clear the colon in preparation of food arriving in the colon ]]> 2020-02-03 12:37:20 UTC https://padlet.com/dilewis2/y5ga4zmdaai7/wish/439577086