Nervous System Flashcards
What are the supporting cells in CNS and PNS
Schwan cells in PNS which myelinate one axon, Oligodendrocytes in CNS which myelinate several axons
Different types of neurons
Multipolar (normal looking, one axon and many dendrites), Bipolar (One axon and one dendrite), Pseudo unipolar (Bipolar but nucleus is offset)
Difference between white and grey matter
Grey matter- less myelination but more cell bodies
White matter - More myelination but less cell bodies
Links the two sides of the brain together
Corpus Callosum
Three regions of the brain
Forebrain - cerebrum, thalamus, hypothalamus
Midbrain- Narrow connection of forebrain to hindbrain
Hindbrain- medulla oblongata, pons, cerebellum
Brainstem = midbrain, pons, medulla oblongata
Folds and groves of brain
Folds are called gyri and grooves are called sulci
Meninges
Pia mater-closest layer to brain follows all irregularities of brain surface, under blood vessels
Arachnoid mater- Subdural layer with projections to pia mater which forms subarachnoid space for CSF
Dura mater- External dense connective tissue, protection
Dural folds
Dura mater extends inward to form flat partitions that subdivided the cranial cavity and limit movement of the brain within cranium.
Cerebrospinal fluid
Fills the subarachnoid space and the central hollow cavities of the brain and spinal cord. Protects and nourishes neural tissue, removes waste. Brian and spinal cord naturally float in CSF which prevents them form being crushed.
CSF production
Produced in choroid process, some runs into central canal of the spinal cord but most enters the subarachnoid space through lateral and median apertures.
Spinal cord functions
Spinal nerves attach to it, ascending and descending tracts traveling in white matter, sensory motor integration in its grey matter (reflexes)
Horns of spinal cord
Ventral- Supply muscles and glans, size varies down spinal cord reflecting the amount of skeletal muscle being affected by it.
Dorsal- interneurons, receive info from sensory neurons who’s cell bodies lie in central root ganglion
