Chapter 11 & 12 - Nervous System Flashcards
What does the central nervous consist of?
The CNS consists of the brain and spinal cord
What are the regions and organizations of the CNS?
The regions and organizations are…
- Brain
- cerebral hemispheres
- diencephalon
- brain stem (midbrain, pons, and medulla)
- cerebellum
What are the characteristics of the ventricles of the brain?
The characterisitcs of ventricles are…
- connected one another and to the central canal of the spinal cord
- lined by ependymal cells
- contain cerebrospinal fluid
What are the ventricles of the brain?
The ventricles are…
- two C-shaped lateral ventricles in the cerebral hemispheres
- third ventricle in the diencephalon
- fourth ventricle in the hindbrain
What are the two C-shaped latertal ventricles of the cerebral hemispheres seprated by?
The two C-shaped lateral ventricles are separated by the septum pellucidum
What is the third ventricle in the diencephalon?
The third ventricle is continuous with fourth ventricle via cerebral aqueduct (Aqueduct of Sylvius)
Where is the fourth ventricle located?
The fourth ventricle is median and lateral apertures connect fourth ventricle to subarachnoid space
What are some surface markings of the cerebrum?
The surface markings of the cerebrum are…
- ridges (gyril)
- shallow grooves (sulci)
- deep grooves (fissures)
What are the four lobes of the brain?
The four lobes are…
- frontal
- parietal
- temporal
- occipital
What is the major function of the frontal lobe?
The frontal lobe deals with the motor cortex
What is the major function of the parietal lobe?
The parietal lobe deals with the sensory
What is the major function of the temporal lobe?
The temporal lobe deals with the auditory
What is the major function of the occipital lobe?
The occipital lobe deals with visual
What is the site of the conscious mind?
The site of the conscious mind is the cerebrum: awareness, sensory perception, voluntary motor initiation, communication, memory storage, understanding
What are the two hemispheres of the brain connected by?
The two hemispheres of the brain are connected by corpus callosum
What are the three paired structures of the diencephalon?
The three structures of the diencephalon are…
- thalamus
- hypothalamus
- epithalamus
What are the characteristics of the thalamus?
The characteristics of the thalamus are…
- superolateral walls of the third ventricle
- sorts, edits, and relays information
- processes sensory information
- perceives pain and pressure
What are the characteristics of the hypothalamus?
The characteristics of the hypothalamus are…
- forms the inferolateral walls of the third ventricle
- regulates body temperature, food intake, water balance, and thirst
- regulates sleep and the sleep cycle
- controls release of hormones by the anterior pituitary
- produces posterior pituitary hormones
What are the characteristics of the epithalamus?
The characteristics of the epithalamus are…
- most dorsal portion of the diencephalon; forms roof of the third ventricle
- pineal gland (body) - extends from the posterior border and secretes melatonin (helpts regulate sleep-wake cycles)
What are the three regions of the brain stem?
The three regions of the brain stem are…
- midbrain
- pons
- medulla oblongata
Where is the midbrain located?
The midbrain is located between the diencephalon and the pons
What is the cerebral peduncles of the midbrain?
The cerebral peduncles contain pyramidal motor tracts
What are the cerebral aqueduct of the midbrain?
The cerebral aqueduct is the channel between third and fourth ventricles
What is the midbrain nuclei?
The midbrain nuclei is a nuclei that controls cranial nerves III (oculomotor) and IV (trochlear)
What is the corpora quadregimina?
The corpora quadregimina is…
- domelike dorsal protrusions
- superior colliculi - visual reflex centers
- inferior colliculi - auditory relay centers
What is the substantia nigra?
The substantia nigra is the dopamine releasing nuclei
What is the red nucleus?
The red nucleus is the relay nuclei for some descending motor pathways
What are the characteristics of the pons?
The characteristics of the pons are…
- forms part of the anterior wall of the fourth ventricle
- located between the midbrain and medulla
- origin of cranial nerves V (trigeminal), VI (abducens), VII (facial)
- nuclei that help maintain normal rhythm of breathing
What are the three centers of the medulla oblongata?
The three centers of the medulla oblongata are…
- autonomic reflex center
- cardiovascular center
- respiratory center
What does the cardiovascular center of the medulla oblongata do?
The cardiovascular center does…
- adjusts force and rate of heart contraction
- vasomotor center adjusts blood vessel diameter for blood pressure regulation
What does the respiratory centers of the medullary oblongata do?
The respiratory centers do…
- generate respiratory rhythm
- control rate and depth of breathing, with pontine centers
What are some additional centers regulation of the medulla oblongata?
The additional centers of the medulla oblongata are…
- vomiting
- hiccuping
- swallowing
- coughing
- sneezing
What are the characteristics of the cerebellum?
The characteristics of the cerebullum are…
- dorsal to the pons and medulla
- controls skeletal muscle contraction and coordinates body movements
- cerebellar peduncles - three paired fiber tracts connect the cerebellum to the brain stem
What are the three paired fiber tracts of the cerebellar peduncles?
The three paired fiber tracts are…
- superior peduncles connect the cerebellum to the midbrain
- middle peduncles connect the cerebellum to the pons
- inferior peduncles connect the cerebellum to the medulla
What are the protections of the brain?
The protections of the brain are…
- bone (skull)
- membranes (meninges)
- watery cushion (cerebrospinal fluid)
- blood-brain barrier
What are the characteristics are the meninges?
The characteristics of the meninges are…
- cover and pretect the CNS
- protect blood vessels and enclose venous sinuses
- contrain cerebrospinal fluid CSF
- form partitions in the skull
What are the three layers of the Meninges?
The three layers of the Meninges are…
- dura mater
- arachnoid mater
- pia mater
What are the characteristics of the Dura Mater?
The characteristics of the dura mater are…
- most superficial
- strongest
- dense irregular connective tissue
What are the characteristics of the Arachnoid mater?
The characteristics of the arachnoid mater are…
- middle layer with weblike estensions
- separated from the dura mater by the dubdural space
- subarachnoid space contains CSF and blood vessels
- arachnoid villi permit CSF reabsorption
What are the characteristics of the pia mater?
The characteristics of the pia mater are…
- inner layer of delicate vascularized connective tissue that clings tightly to the brain
What is the composition of the cerebrospinal fluid?
The composition of the cerebrospinal fluid are…
- watery solution
- less protein and different ion concentrations than plasma
- constant volume
What is the function of cerebrospinal fluid?
The function of the cerebrospinal fluid is…
- gives buoyancy to the CNS organs
- protects the CNS from blows and other trauma
- nourishes the brain and carries chemical signals
What is the purpose of the blood-brain barrier?
The purpose of the blood-brain barrier is…
- helps maintain a stable enviroment for the brain
- separates neurons from some bloodborne substances
What is the composition of the blood-brain barrier?
The composition of the blood-brain barrier is…
- continuous endothelium of capillary walls
- basal lamina
- feet of astrocytes
Why is the blood-brain barrier a selective barrier?
The blood-brain barrier is selective by…
- allows nutrients to move by facilitated diffusion
- allows any fat-soluble substances to pass, including alcohol, nicotine, and anesthetics
What is the location of the spinal cord?
The location of the spinal cord is…
- begins at the foramen magnum
- ends as conus medullaris at L1 vertebra
What are the functions of the spinal cord?
The functions of the spinal cord are…
- provides two way communication to and from the brain
- contains spinal reflex centers
What is the gross anatomy of the spinal cord?
The gross anatomy of the spinal cord are…
- protected by bone, meninges, and CSF
- Cushion of fat and a network of veins in the epidural space between the vertebrae and spinal dura mater
- CSF in subarachnoid space
Define:
Cervical and lumbar enlargements
Cervical and lumbar enlargements are the nerves serving the upper and lower limbs emerge here
Define:
Conus medullaris (medullary cone)
The conus medullaris is tapered, cone-shaped end of spinal cord
Define:
Filum terminale
Filum terminale is fibrous extension from conus medullaris; anchors the spinal cord to the coccyx
Define:
Cauda equina
Cauda equina is the collection of nerve roots at the inferior end of the vertebral canal
What is the cross sectional anatomy of the spinal cord?
The cross sectional anatomy of the spinal cord is…
- central canal is continuous with ventricular system of the brain
- two lengthwise grooves divide cord into right and left halves
- gray matter is located in the center
- white matter is located outside of the gray matter
What are the two lengthwise grooves that divide the spinal cord into left and right halves?
The two lengthwise grooves are…
- ventral (anterior) median fissure
- dorsal (posterior) median sulcus
Define:
Dorsal horns
Dorsal horns are interneurons that receive somatic and visceral sensory input
Define:
ventral horns
Ventral horns are somatic motor neurons whose axons exit the cord via ventral roots
Define:
lateral horns
Lateral horns are sympathetic neurons; only found in the thoracic and lumbar regions
Define:
Dorsal root (spinal) ganglia
Dorsal root ganglia contains cell bodies of sensory neurons
What are characteristics of the white matter?
White matter consists mostly of ascending (sensory) and descending (motor) tracts
What are the tracts of the white matter?
The tracts of the white matter are…
- located in three white columns; dorsal (posterior), lateral, and ventral (anterior)
- each spinal tract is composed of axons with similar functions
What are the terms of the gray matter?
The terms of the gray matter are…
- dorsal horns
- ventral horns
- lateral horns
- dorsal root (spinal) ganglia