lab 8 and 9

reflexes

motor responses

somatic reflex

activates skeletal muscle

autonomic reflex

controls visceral effectors such as smooth or cardiac muscle, or glands

proprioceptors

tendon organs and muscle spindles, supply info to the CNS about muscle placement

myotatic reflex

knee jerk, monosynaptic but triggers polysynaptic muscles

stretch reflex

stimulates muscle contractions with stretching (mono)

tendon reflex

helps muscles relax during high tension (poly)

plantar reflex

running a blunt object down the lateral aspect of the sole of the foot and indicates spinal cord integrity from L4 to S2

babinski's sign

impaired plantar reflex, common in infants

light reaction time

190 ms

sound reaction time

150 ms

touch reaction time

155 ms

sound stimulus to reach brain

8-10 ms

visual stimulus to reach brain

20-40 ms

nerves in PNS?

cranial and spinal

order of nerve coverings

epineurium, perineurium, endoneurium

what do glial cells in the CNS do

make cerbral spinal fluid

glial cells in CNS

astrocytes, microglia, oligodendrocytes, ependymal

glial cells in PNS

satellite and schwann cells

perivascular feet

anchor neurons to blood vessels and neuronal surfaces

rough ER granules in the soma

stain darkly called nissl bodies

what divides the left and right hemispheres of the cerebrum?

longitudinal fissure

what are the hemispheres covered in?

gray matter, unmyelinated

fold in the cerebral cortex

gyrus

groove in cerebral cortex

sulcus

what connects the cerebra hemispheres?

white matter called the corpus callosum

pyramidial cells

multipolar neurons in the cerebral cortex

diencephalon components

thalamus, hypothalamus, epithalamus

infundibulum

hypothalamic tissue that contains the pituitary gland

epithalamus

contains pineal gland

what does the pineal gland secrete

melatonin

whats the pineal gland under control of

suprachiasmatic nucleus of hypothalamus

what does the cerebellum contain

purkinje cells

order of layers in cerebellum

molecular, purkinje, granular

components of the brain stem

midbrain, pons, medulla oblongata

midbrain function

inhibits muscle movements

pons function

communication

medulla oblongata function

cardiovascular and respiratory systems

olfactory nerve I

sense of smell

optic nerve II

sense of vision

oculomotor nerve III

moves eyes

trochlear nerve IV

moves eyes

trigeminal nerve V

senses fibers and helps chew food

abducens nerve VI

controls lateral rectus

facial nerve VII

facial expression

vestibulocochlear nerve VIII

senses hearing and balance

glossopharyngeal nerve IX

innervates tongue and throat

vagus nerve X

supplies movement and senses of the thorax and abdomen

spinal accessory nerve XI

moves sternocleidomastoid and trapezius

hypoglossal nerve VII

moves tongue muscles

meissner corpuscles

light pressure receptors of the skin