Lab Unit 13 - Central Nervous System Flashcards
THE BRAIN
The most complex organ of the nervous system, consisting of a folded, hollow, whitish-gray mass of nervous tissue, connective tissue, and modified epithelium.
4 REGIONS OF THE BRAIN
- Cerebral hemispheres (cerebrum)
- Diencephalon
- Cerebellum
- Brainstem
5 LOBES OF THE BRAIN
- Frontal lobe
- Parietal lobe
- Temporal lobe
- Occipital lobe
- Insula
CEREBRAL CORTEX
The outer 2 millimeters of gray matter of the cerebrum.
GRAY MATTER
Gray matter includes cell bodies, dendrites, and unmyelinated axons.
WHITE MATTER
White matter is bundles of myelinated axons. Found deep to gray matter of the cerebral cortex.
BASAL NUCLEI
Basal nuclei are clusters of gray matter spread throughout the white matter of the cerebrum. Basal nuclei monitor voluntary motor functions.
CORPUS CALLOSUM
The largest tract of cerebral white matter, connects the left and right cerebral hemispheres.
DIENCEPHALON
Deep to the cerebral hemispheres in the central core of the brain. Composed of 3 main parts: the thalamus, hypothalamus, and epithalamus.
3 PARTS OF THE DIENCEPHALON
- Thalamus
- Hypothalamus
- Epithalamus
THALAMUS
Large central egg-shaped mass of gray and white matter. Makes up 80% of diencephalon. The thalamus is the major integration and relay center that edits and sorts info going to the cerebrum. The thalamus is the gateway into the cerebrum.
HYPOTHALAMUS
The hypothalamus regulates the endocrine system, monitors the ANS, monitors the sleep-wake cycle, and controls thirst, hunger, and body temperature.
The pituitary gland is connected to the hypothalamus vis the infundibulum.
EPITHALAMUS
The epithalamus is the posterior and superior part of the diencephalon. It contains an endocrine organ called the pineal gland that secretes melatonin, helping to regulate the sleep-wake cycle.
3 PARTS OF THE BRAINSTEM
- Midbrain
- Pons
- Medulla oblongata
MIDBRAIN
The most superior portion of the brainstem. Has roles in movement, sensation, and certain reflexes.
PONS
Inferior to the midbrain and bulges anteriorly. The pons controls rhythm for breathing and the sleep cycle.
MEDULLA OBLONGATA
Works with the pons to control ventilation. The MO regulates heart rate, blood pressure, and certain reflexes such as vomiting.
CEREBELLUM
The third major component of the brain, composed of gray matter (cerebellar cortex) and white matter (arbor vitae). The cerebellum is responsible for coordinating and planning motor activities and is critical in reducing and preventing motor error with movement.
DURA MATER
The toughest and outermost meninx. Thick and leathery. Cranial dura mater has 2 layers (periosteal and meningeal layers). Spinal dura mater has only one layer.
ARACHNOID MATER
The middle meninx. Allows CSF to re-enter the blood.
PIA MATER
“Tender mother.” The thinnest, innermost meninx. Cranial pia mater follows the contours of the gyri and sulci, and is richly supplied with blood vessels. In the spinal meninges, pia mater has small extensions called denticulate ligaments.
DENTICULAR LIGAMENTS
Small extensions of pia mater in the spinal meninges. Denticulate ligaments secure the spinal cord to the vertebral column.
FILUM TERMINALE
Long, fibrous extensions of pia mater that continue long after the spinal cord ends. These eventually attach to the coccyx.
VENTRICLES
Hollow spaces in the brain that are filled with CSF. There are 4 ventricles: 2 lateral ventricles, a third ventricle, and fourth ventricle.
