Lecture 4 Flashcards
What is the pathway of light?
light enters through the pupil to the retina to chemically stimulate cones and rods to release neurotransmitters and reach action potential in the bipolar cells to send to ganglia cells and to optic nerve to tract to disc and to thalamus and visual cortex in occipital lobe
What light do rods and cones translate?
Rods - white and black light / cones - blue green red light
How are images viewed by the retina?
reduced and inverted
What are the three bones in the ear?
malleus, incus, stapes
What are the sections of the cochlea?
scale vestibuli, cochlear duct, spiral organ, scala tympani
What are the 3 membranes inside the cochlear?
vestibular membrane, tectoral membrane, basilar membrane
Where are the hairs connected to in the ear?
cochlear duct
What nerve do the auditory hairs stimulate?
they release neurotransmitters to excite the neuron of the cranial nerve 8
Why type of potential do the hair cells stimulate by the vibration?
receptor potential to open K channels completely (not action potential)
What is responsible for the sense of equilibrium?
vestibule and semicircular canals
Somatic vs. Autonomic nervous system
motor neurons innervate voluntary muscle vs. Motor neurons innervate smooth muscle and glands
How many motor neurons are associated with the sympathetic ns and characteristics?
two. First is myelinated from the brain to CNS and ONLY releases ach. The second is unmyelinated and goes from the CNS to the effector and releases ach( only when sweat) or norepinephrine
What are the two divisions of autonomic ns?
sympathetic (fight flight) and parasympathetic (rest digest)
What spinal segments do sympathetic ns comes from?
t1 to L2
Where do the first sympathetic neurons originate?
CNS
Where do the first parasympathetic neurons originate?
brain stem or CNS
What spinal segments do parasympathetic ns come from?
c1 to c4 and s2 to s4
Why do some neurons have a ganglion and others don’t?
Pre and post ganglion neurons are used for sympathetic autonomic nervous systems for involuntary smooth muscle activation
Upper and lower motor neurons are used in the corticospinal tracts somatic nervous system in voluntary skeletal muscle movements
What brain part is the main regulator of the autonomic ns?
hypothalamus to medullar oblong to autonomic ns to sns/pns
How many neurons are associated with the somatic ns?
2: upper and lower motor neuron
What is the distinction btw upper and lower motor neuron?
upper comes from the brain CNS and the lower comes from the spinal cord CNS to the effector
What are the 3 types of movement in somatic ns?
reflexes, voluntary, rhythmic
Where is somatic ns movement first decided?
Motor cortex sends to cerebellum to thalamus to corticospinal tract to upper and lower motor neurons and muscle
What is the corticospinal pathway?
consists of the descending tract to effector using upper and lower motor neurons to skeletal muscle
If the upper neurons are damaged what happens?
the reflex arc is still intact but spastic paralysis and exaggerated reflexes will occur
If the lower neurons are damaged what happens?
loss of reflex arc
What part of the brain is used to speak?
left cortex
What parts are associated with speech?
wernicke’s area
What happens if the wrnicke’s area is damaged?
cannot understand written or spoken words but can speak gumbled words
What happens if there is damage to the Broca’s area?
can understand words but not speak
