module 4 Flashcards
gray matter vs white matter
gray matter: contains nerve cells and their processes
white matter: contains nerve fibers that connect the brain with the spinal nerves
cranial nerves and their function
- emerge from brain stem
- cranial nerves do not have dorsal or ventral roots
- afferent sensory nerves (optic)
-efferent motor nerves (hypglossal)
-mixed cranial nerves (vagus)
spinal cord anatomy
-continuations of the medulla oblongata
-divided into segments each with a pair of spinal nerves
- in all species the first spinal nerve emerges from the vertebral column at the joint between the skull and the first cervical vertebra
spinal cord tract
-bundle of fibers within CNS is called a tract
-spinal cord tract provides routes for conduction of information to and away from the brain
Cerebellum
- coordinates movement, smoothness of actions, and maintenance of equilibrium (hand-eye coordination)
-is damages, the eyes can follow an object but animal cant pick it up
hindbrain
contains brainstem
brainstem
pons: regulates breathing activity
medulla oblongata: contains centers that control several autonomic functions (cardiovascular activity, swallowing, vomiting, digestion
midbrain: mesencephalon
forebrain
contains cerebral cortex, basal ganglia, thalamus, and hypothalamus
cerebral cortex
forebrain telecephalon
- complex control center with somatosensory and higher motor functions
- motor portion response to sensory stimuli by sending commands to skeletal muscle (catching or copulation)
- somatosensory functions include receiving and integrating touch, temperature, pain, and pressure sensations
basal ganglia
forebrain telecephalon
important for motor coordination; a switch center for impulses from motor system
types of papillae (taste buds)
foliate: moderate numbers on tongue
located on tongues lateral surface and flat anterior surface
fungiform: moderate numbers on tongue
located on tongues lateral surface and flat anterior surface
circumvallate: most numerous papillae that contain taste buds
found on posterior (base) surface of the tongue in the shape of a v
hypothalamus
forebrain diencephalon
important for homeostasis
contains releasing hormones that influence the anterior pituitary
synthesizes oxytocin and ADH, which are stored in the posterior pituitary
contains centers for regulation of body temp, thirst, and hunger
plays a role in sexual response and mating behaviors
eustachian tube
equalizes pressure between atmosphere and middle ear
thalamus
forebrain diencephalon
major relay center for sensory information on its way to the cerebellum
attenuation reflex
reduces intensity of low-frequency sound in order to mask them as background noise
{protects cochlea} from high frequency vibrations
involves contraction of stapedius muscle and tensor tympani muscle
muscles contact, movement of ossicles is dampened and sensitivity of acoustic apparatus decreases
middle ear
cavity filled with are, containing three small, conected bones referred to as ossicles (malleus, incus, and stapes) or (hammer, anvil and stirrup)
inner ear
contains the cochlear and vestibular systems
contains saccule that is integrative in both systems
cochlear vs vestibular system
cochlea: receives and transmits sounds and vibrations
vestibular: detects changes in head position and movement
outer ear
consists of external pinna (auricle) and external (auditory) ear canal (acoustic meatus)
cochlea
complex coiled organ of inner ear that is filled with fluid
the three canals of the cochlea
scala media (cochlear duct): filled with endolymph fluid
scala tympani (below scala media separated by basilar membrane): filled with perilymph fluid
scala vestibuli (above scala media): contains perilymph fluid
fundic exam
examination of retina
atropine used (pupil dilation)