Chapter 2: Anatomy of the Nervous System Flashcards
(42 cards)
Central Nervous System (CNS)
Consists of the brain and spinal cord.
Incoming/Ascending Signals
Signal from the PNS moving to the CNS.
Outgoing/Descending Signals
Signals from CNS to PNS.
Afferent Information
Information arriving in the CNS.
Efferent Information
Information leaving the CNS.
Rostral (Anterior)
Forward parts of the brain.
Weight of the Brain
Adult brain weighs 1.5 KG — 2% of body weight. Uses 1/5 of the body’s total energy.
Caudal (Posterior)
Back parts of the brain.
Medial
Centre parts of the brain.
Lateral
Sides of the brain.
Dorsal (Superior)
Top of the brain.
Ventral (Inferior)
Bottom parts of the brain.
Coronal Slice
Anterior to posterior view.
Horizontal Slice
Dorsal to ventral view.
Parasagittal Slice
Never symmetrical. Parallel to midline.
-sagittal
Derived from Latin word meaning arrow.
White Matter
Pathways of communication. For neurons to send rapid signals, they can be modified with layers of fatty lipids called myelin. Modification causes light to reflect making it look white.
Gray Matter
Sections of darker pink/gray tissue. Often dense with cell bodies.
Decussation
Information crossing from one hemisphere to the other.
Corpus Callosum
A bundle of nerve fibers that connects the left and right hemispheres of the brain, enabling communication and coordination between them.
Three Germ Layers
Mesoderm, ectoderm, endoderm.
Ectoderm
Eventually develops into the nervous system. Folds into itself and once it merges with the surface, the neural tube is formed.
The neural tube
Forms during the 3rd-4th week of gestation. Eventually becomes the CNS.
Early Neural Tube Development
Starts with three main components – three-vesicle stage. A week later it becomes the five-vesicle stage.