Control of the Alimentary System Flashcards
which two factors are involved in the control of the alimentary system
nervous control and hormonal control
which nerves are involved in control of the alimentary system
nerves from both the somatic and autonomic branches of the nervous system
how can the somatic branch of the peripheral nervous system be further divided
sensory and motor
how can the autonomic nervous system be further divided
parasympathetic and sympathetic
which group of hormones control the alimentary system
gastrointestinal tract hormones
what are the gastrointestinal tract hormones
- cholecystokinin
- gastrin
- gastric inhibitory peptide
- secretin
what does secretin do
reduces gastric acid secretion and increases bicarbonate from the pancreas
what is the sympathetic nervous system responsible for
fight or flight; increased heart rate and breathing, reduced gut motility
describe the parasympathetic nervous system
in charge of rest and digest, reducing heart rate and breathing and increasing gut motility
what is cholecystokinin
hormone secreted by the duodenum endocrine cells that helps in digestion of fats and protein
what is CCK
cholecystokinin
describe gastrin
secreted by the G cells of the stomach to stimulate hydrochloric acid by the parietal cells
what is the main role of gastric inhibitory peptide
increase insulin secretion
where in the gastrointestinal tract are the hormones most active
at the level of the stomach
what does the mouth and pharynx function in
secretion of saliva and motility for chewing and swallowing
describe saliva secretory control
some cranial nerves
how does saliva function
both chemically and mechanically
how does saliva function chemically
gustation and olfaction (taste and smell) important to note that smell has a minor effect in human beings
how does saliva function mechanically
functions in chewing and loading the periodontal ligaments
do conditioned reflexes have a large role in humans
no very minor
which cranial nerve is VII
facial nerve
which cranial nerve is IX
glossopharhyngeal
which cranial nerve is V
trigeminal nerve
give a quick description of Ivan Pavlov’s dogs experiment
discovery of classical conditioning whereby the ringing of the bell when presenting the dogs with food stimulated saliva production whenever the bell was rung, even when food was not present
what are the main stimulus that go to the brain to stimulate secretion from the salivary glands
visual
olfactory
mechanical
chemical
what is visual stimulus for saliva secretion
sight of the food
what is olfactory stimulus for saliva secretion
smell of food
what is mechanical stimulus for saliva secretion
chewing
what is chemical stimulus for saliva secretion
taste which is most potent when there is acid content
describe the process of chewing
uses the jaw, facial and tongue muscles
skeletal muscle in type, and is controlled by somatic nerves
voluntary, autonomic control via the central nerves V, VII and XII
describe the process of swallowing
uses the jaw, tongue and pharyngeal muscles
skeletal muscle in type and is controlled by somatic nerves
autonomic and reflex control is via the central nerves V, IX, X, XII and swallowing centre
which cranial nerve controls the oesophagus
X
which cranial nerve is V
trigeminal
which cranial nerve is VII
facial muscles
which cranial nerve is XII
hypoglossal
which cranial nerve is IX
glossopharyngeal
what is secreted in the stomach
gastric juice
what is involved in stomach motility
filling and relaxation
mixing
propulsive movements (peristalsis)
emptying
what are the phases to gastric activity
cephalic phase
gastric phase
intestinal phase
describe the mechanical stimuli of the cephalic phase of gastric activity
the muscles of mastication
describe the chemical stimuli of the cephalic phase of gastric activity
taste and smell