Final-exam 1 Flashcards
the neurotransmitter responsible for the transmission of a painful stimulus between first and second order neurons.
Substance P
The sequence of events for signal transduction (stimulation of a target cell by second messenger system is:
hormone binds to membrane receptor, G-protein activated, membrane enzyme generated second messenger
The meaty, beefy flavor you experience when you eat meat is because of :
the combined stimulus of several kinds of taste buds
Where are taste buds found?
Tongue, cheeks, palate
What is the gate control theory of pain modulation?
Inhibitory interneurons can modulate second order pain neurons, are activated by collaterals of afferent fibers that are associated with mechanical stimuli and are inhibited by collaterals from the nociceptor afferent
A drug that competitively blocks the neurontransmitter receptors of the bipolar cells of the retina would
result in constant depolarization of ganglion cells and create a bright whiteout effect
The neural pathway for transmission of auditory action potential to the auditory cortex is
cranial nerve VIII to the thalamus to the cortex
What is the stimulus for nociceptors
pain
An injection of norepinephrine would most strongly emulate secretions from
post ganglionic nerve synapses of the sympathetic nervous system
Concerning hormone secretion over a 24 hour period, the general pattern that we observe is that
secretion occurs in pulses and total secretions varies by time of day
Blood vessels in most regions of the body except for the lungs
have alpha receptors that are more responsive to norepinephrine than epinephrine
Pre-ganglionic neurons of the ANS are characterized as
being lightly myelinated
Normal elimination of hormones from circulation is most often accomplished by
metabolism in the liver
The process in which a sensory reception converts a stimulus into a graded potentioal is called
Signal transduction
When the ciliary muscles are relaxed the lens is relatively _______, allowing the ey to focus on objects that are ________
flat : distant
Nicotinic receptors in the ANS
respond only to acetylcholine, are found in pre-ganaglinonic synapses of the sympathetic, parasympathetic, and adrenal medulla, and are fast acting excitatory receptors
One attribute of the photopigments in the rods and cones is that there is a genereal sensitivity to green light. what pigment is the exception and not green sensitive
blue opsin
which of the following is correct concerning peptide based (non steroidal) hormones?
They include all hypothalamic and pituitary hormones
High frequency sounds are detected in the inner ear where
proximal end of organ of corti
An inherited defect in the structure of rhodopsin in the receptors of the retina would result in
impairment of low light vision
the receptors that make up the tissue called the olfactory epithelium
are regenerated from epithelial stem cells
What does lateral inhibition do?
increases contrast between sensory pathways within the nervous system, enhances sensory localization, inhibits neurons receiving information from afferents associated with neighboring receptive fields
Damage to the right dorsal columns of the spinal cord at the thoracic level would cause
impaired touch sensation of the right leg
How can epidural administration of opiates block pain?
by binding to opioid receptors in the somatosensory cortex and inhibiting the perception of pain
cones of the eye
synapse mostly one cone to each bipolar cell of their natural pathway
Damping of vibration of the ossicles in the middle ear to reduce sensitivity to sound is caused by
contractions of the tensor tympani
Rods and cones of the eye
periodically replace their outer segments
the ability of the organ of corti to differentiate different wavelengths of sound is possible because
the perilymph absorbs sounds differently and the basilar membran has variable resistance to vibration with different wavelengths
physical protection of the eye is provided for by
the bony prominences of the frontal and maxillary bones
reduction of pupil diameter is an autonomic reflex that
is mediated by parasympathetic excitation from the superior colliculi
Direct acting hormones have what properties?
they are steroids or eiconsanoids and receptors for the hormones are found within the cell
The structures of the ear that are most sensitive to changes in direction or speed are
the semicircular canals
What organs or tissues don not receive dual innervation from the sympathetic and parasympathetic NS are
blood vessels
Hair cells are able to transmit information about changes in position or speed because
bending of the cilia in opposite directions will increase then decrease the frequency of action potentials
Concerning the distribution of the rods and cones in the retina
virtually all cones are confined to the macular region of the retina
Amplification of sound by the pinna is the result of
the ratio of diameter of the ear to the ear canal
permissive hormones are those that
are necessary to permit other hormones to function properly
Taste and olfactory senses differ in that
taste receptors are epithelial and olfactory receptors are neural cells
oxygen and nutrients are supplied to the inner tissues of the eye
by blood vessels entering through the optic disk
Somatic sensations include?
touch, proprioception, and pain
another name for an afferent sensory neuron is
first order neuron
action potentials generated by the taste buds are conducted to the cerebral cortex
by the facial, glossopharyngeal and vagus nerves and must pass through the thalamus like all other sensory stimuli
Tears are protective of the eye why?
because the contain antibodies
the sympathetic trunk of the ANS is supplied by nerves from
the thoracic spinal nerves and the lumbar spinal nerves
What secretes the aqueous humor
the ciliary body
