Nervous System Flashcards
Homeostasis
Study of internal environment. Controlled through negative feedback systems.
Claude Bernard
Described Milleu interieur: internal environment. Idea of having a constant internal environment despite external change.
Walter cannon I
Coined homeostasis
What are the main two parts of the nervous system
Central and peripheral
Central nervous system organs
Brain and spinal cord
Peripheral nervous system organs
Everything except brain and spine
Glial cells
Support neurons physically and metabolically
What puts myelin on the axon?
Oligodendrocytes (cns) or Schwann cells (pns)
What happens if neural tube doesn’t close all the way?
Causes birth defects like spinal Bifida and anencephaly
What does loss of myelin cause
Multiple schlerosis
What is the organization of Grey and white matter on the brain?
Grey matter is surface, white matter is center of brain
What is the organization of grey and white matter in the spine?
Grey matter is inside. White matter is surface.
What are the three layers of protection to CNS/brain?
Cranium and vertebral columns, meningeal membrane, cerebral spinal fluid.
What is the meningeal membrane?
Consist of the dura mater (hard), arachnoid layer (spider like), and pia mater (soft). Protects brain from the skull.
What is cerebral spinal fluid?
Formed by blood brain barrier, has selective permeability of capillaries to keep bad things away from brain.
What happens if lack of blood to brain?
Stroke occurs
Cauda equina
Place where spinal drugs are inserted and CSF samples are taken.
How many pairs of spinal nerves?
31; 8 cervical 12 thoracic 5 lumbar 5 sacral and 1 coccygeal
Dermatomes
Sensory region on body surfaces. Innervates by specific spinal nerves in specific places.
