Physio exam 2
secretin
A hormone secreted by the small intestine (duodenum) in response to low pH (e.g., from stomach acid). It promotes the release of bicarbonate from the pancreas to act as a buffer.
Norepinephrine
A neurotransmitter involved in arousal, as well as in learning (attention) and mood regulation, temperature, and pituitary PNS effects- sym
Which of the following events depolarize the neuronal cell membrane?
A. Ca2+ enters the cell B. Na+ enters the cell
pepsinogen vs pepsin
Pepsinogen- released by the gastric glands unactivated, activated by eating, so it won't digest the gastric gland cells that produce it Pepsin- activated by HCl to break down proteins into polypeptides, decrease ph in stomach
trochlear nerve
Eye movement (superior oblique muscle) Damage causes double vision
K cells (duodenum, jejunum)
GDIP
G cells of the stomach secrete
Gastrin
parietal cells of stomach
HCL and IF
Glucagon-like peptide 1 (GLP-1)
Release triggered by a by a meal that has carbohydrates and fats entering the intestine; causing the pancreas to release insulin, while inhibit activity of the stomach , and inhibiting glucagon release; known to be associated with the sensation of being full
Secretin
Released when chyme arrives in the duodenum; increases secretion of bile (by the liver) and of buffers (by the pancreas) and reduces gastric motility and secretory rates
duct cells of pancreas
Secret HCO3- to neutralize acid coming from stomach
Gastrin
Secreted (when stimulated by the vagus nerve or when food arrives in the stomach) and by enteroendocrine cells in the duodenum (when exposed to large quantities of incompletely digested proteins); promotes increased stomach motility and stimulates production of gastric acids and enzymes
Carbohydrate digestion begins when the complex carbohydrate starch is broken down into maltose. Which enzymes catalyze the breakdown of maltose into monosaccharides, and where are the enzymes found?
disaccharidases located on the intestinal brush border
conduction
electricity (brain sends electrical signals into chemical)
Ribonuclease
enzyme that breaks down RNA
lipase
enzyme that breaks down fat
amylase
enzyme that breaks down starch
Acetylcholine
excitatory neurotransmitter that enables learning and memory and also triggers CNS- facilitates nerve impulses PNS- muscle contraction, glandular, parasym
trigeminal nerve
facial muscles, face sensations, chewing
alpha cells of pancreas
glucagon
axon hillock
has highest sensitivity to ap, trigger zone
Microglial cells (CNS)
help with macrophages (immune cells) in CSF
Ependymal cells (CNS)
helps with BBB, and circulates CSF
HCL is stimulated by?
histamines, H2 receptors
Gastrin
hormone secreted in the stomach that stimulates secretion of HCl and increases gastric motility, acidic
CCK cells (small intestine)
hormone, bile
Somatostatin
inhibits gastrin
beta cells of pancreas
insulin
Satellite cells (PNS)
interneurons, release neurotransmiters (chemical signal)
Which of these white matter tracts (above) is utilized to convey sensory action potentials related to temperature, pain and coarse touch sensations to the brain? C
lateral spinothalamic pathway
tonic contractions
long
Elevated levels of potassium in extracellular fluid (blood, interstitial fluid, and plasma) is called hyperkalemia. How would this effect neuronal function?
lowers stimulus threshold / increases sensitivity
neural convergence
many to one
abducens nerve
moves eye laterally
Spinal Accessory
moving head and shoulders
myenteric plexus
muscle contraction
oliogendrocytes
myelination of axons in CNS, involves many cells
action potential
nerve impulse, signal nerve sends
Colinergic Receptors
nicotinic (muscle relaxor) and muscarinic both parasym
neural divergence
one to many
Transcytosis is how __________ are absorbed.
peptides
Protein digestion in the stomach is mostly done to start the process of protein digestion into large fragments called
polypeptides
Which of these is used to carry the same kinds of sensations, but more specifically related to fine touch, proprioception or vibration?
posterior column pathway
Schwann cells
produce myelin in PNS
chief cells of the stomach
release pepsinogen and gastric lipase
ECL cells
secrete histamine
S cells of duodenum
secretin
Submusocal plexus
secretions
olfactory nerve
sense of smell
phasic contractions
short
D cells of the stomach
somatostatin
GDIP
stimulates release of insulin
trypsin inhibitor
stops with protein digestion, protects pancreas
In the ascending pathways noted above the second order neurons end where?
thalamus
auditory nerve
the cranial nerve that carries sound from the cochlea of the inner ear to the brain
Action Potentials can not travel backwards because
the long refractory period
optic nerve
the nerve that carries neural impulses from the eye to the brain, eyesight
neurotransmitter re-uptake
the recycling of neurotransmitters where the synaptic vesicle reabsorbs the neurotransmitter following its release
vagus nerve
the tenth cranial nerve that innervates digestive organs, heart and other areas PS nerve
Axonal transport refers to
the use of microtubules to send secretions from the cell body to the axon terminal.
hypoglossal nerve
tongue movements for speech, food manipulation and swallowing
Glossopharyngeal nerve
- swallowing -salivation - gag reflex - sensation from tongue to ear PS nerve
oculomotor nerve
-eye movement -opening of eyelid - constriction of pupil -focusing PS nerve
Which of the characteristics listed are associated with graded potentials ?
A. can be summed B. amplitude decreases with distance C. has no threshold
Interneurons are
A. found only in the CNS B. signal "gate keepers"
Sodium ion channels in the neuron cell membrane are
A. not permeable to potassium B. voltage gated C. mechanically gated
Colinergic Synapses
Ach
Astrocytes (CNS)
BBB, structure and support, pick up K+ and H2O
emulsification
Breakdown of large fat globules into smaller, digestible particles. Bile salts like soap breakdown barrier of lipids
A patient took high doses of antibiotics to help fight a bacterial infection. However, this treatment also killed helpful bacteria in the gastrointestinal tract. Which of the following would you expect?
Decreased digestion of complex carbohydrates and decreased vitamin K, leading to clotting problems
Gastric Inhibitory Peptide (GIP)
Is secreted when fats and carbohydrates (especially glucose) enter the small intestine; inhibits gastric activity and stimulates insulin release at the pancreatic islets; also stimulates duodenal gland activity and lipid synthesis in adipose tissue, and increases glucose use by skeletal muscles
CCK (cholecystokinin)
Secreted when chyme arrives in the duodenum, especially when the chyme contains lipids and partially digested proteins; increases the secretion of pancreatic enzymes and pushes pancreatic secretions and bile into the duodenum; in high concentrations, inhibits gastric activity and appears to have CNS effects that reduce the sensation of hunger
Motilin and (VIP)
Stimulates the secretion of intestinal glands, dilates regional capillaries, and inhibits acid production in the stomach. Motilin is also co-secreted during fasting periods at 1.5 to 2 hr. intervals to trigger sweeping smooth muscle contractions which clear the GI tract and help to initiate preparation for the next ingestion of a meal. Motilin release is inhibited by the ingestion of the next meal.
facial nerve
Taste (anterior 2/3 of tongue); somatosensory (pressure, pain) information from ear; controls muscles used in facial expression. PS nerve
Which is the best example of a short reflex?
The gastrocolic reflex, which occurs when stretch in the stomach increases motility in the large intestine
How is iron absorption regulated?
The liver secretes hepcidin, which causes the breakdown of ferroportin.
intrinsic factor
a gastric secretion that combines with vitamin B12 so that the vitamin can be absorbed, helps with blood clotting, and makes RBC's, pernicious amenia
electrical synapse
a type of synapse in which the cells are connected by gap junctions, allowing ions (and therefore the action potential) to spread easily from cell to cell
Trypsin
an enzyme from the pancreas that digests proteins in the small intestine, inactive form tyrpsinogen, enteropeptidase activates it in bborder
adrenergic receptors
beta (increase hr, and beta blockers decrease hr) alpha (blood vessel constrict, increase bp, alpha blockers decrease bp) both sym = Nep
Which is NOT a similarity between parietal cells and chief cells
both regulate gastric acid secretion
neuroglial cells
brain cells
Enteric Nervous System (ENS)
brain of the digestive system
Acetylcholinesterase
breaks down acetylcholine
pepsin
breaks down protein into polypeptides in stomach
Which enzyme helps produce bicarbonate in pancreatic acini and in duodenal cells? Hint: It is the same enzyme that is active in erythrocytes.
carbonic anhydrase
other protein enzymes
chymotrypsin carboxyopeptidase elastase aminopeptidase in bb
nuclei
clusters of cell bodies in the CNS
ganglia
clusters of neuron cell bodies in PNS