Hindbrain or Cephalon
Posterior part of teh developing brain; becomes the pons, medually, and midbrain
Midbrain or Mesencephalon
Uppermost part of the brainstem
Forebrain or Prosencephalon
Anterior Part of teh developing brain; becomes the cerebrum
Lower section of the hindbrain;
Upper section of the hindbrain; the central canal expands to form the 4th ventricle
The ___ ____ becomes the cerebral aqueduct in the midbrain, connecting the 3rd & 4th ventricle
The posterior region of the forebrain stays in the midline to become the _________
The __ ___ forms the 3rd ventricle
The anterior part of the forebrain. And this structure becomes the cerebral hemispheres; the hemispheres expand so extensively that they envelop the diencephalon.
The covered region of the cortex, and the edges of the folds that cover the _____meet to form the lateral sulcus.
This type of cell lines the neural tube that divide to produce neurons & glia.
The ______ migrate in the neural tube lining by 2 mechanisms: 1. sending a slender process to the brain surface & then hoisting themselves along the process or 2. climbing along radial glia
The moving tip of a growing axon. Provides the process of the neurons in the cortex direct their axons down through the brain to synapse with speicfic neurons in the spinal cord.
In early development when many neurons do not survive. The neurons that die failed to establish the optimal connections with their target cells or were too inactive to maintain their connection
One of the 2 regressive processes that sculpt the developing NS. Neurons may retract their axons from certain target cells while leaving other connections intact
Fast Twitch Muscle
Converted to slow twitch if innervated by a slow motor nueron. type two, fewer capillaries, decreased oxygen, larger in size, more force, quick to tire, short-term contractions for force/power
Slow Twitch Muscle
Can be converted to fast twitch if innervated by a fast motor neuron. type 1, more capillaries, increased oxygen, smaller size, less force, slow to fatigue, long-term contractions
Myelin Sheath Function
Before neurons with long axons become fully functioning their axons must be insulated by a ___ ____, composed of lipids & proteins
The process of acquiring a myelin sheath. This process begins in the 4th fetal month; most sheaths are completed by the end of the 3rd year of life.
Growing into Deficit
Nervous System damage that occured earlier is not evident until the systems damage would normally have become functional. Example: If some of the cortical neurons controlling lower limb movements were damaged at birth, the deficit might not be recognized until the child is more than a year old & had difficulty standing & walking.