May 30, 2012
Today we finished up our notes on the nervous system, and we watched a short video on how a motor neuron works.
Voltage of a resting neuron across its plasma membrane. It is the way we feel senses. When a neuron is in resting potential, there are positive ions on the outside of the membrane and negative ions on the inside. When there is a stimulus (Anything that triggers a nerve signal to start), it goes into action potential.
Action Potential-When a nerve signal is triggered, the neuron goes into action potential. It is when openings on the membrane open and let in positive ions. other openings open and let out negative ions. The inside becomes more positive than the outside, causing our sense to occur. Eventually, the positive ions return outside and the neg. ions return inside, bringing the neuron back to resting potential.
you can get the specifics in the notes, but that is a basic overview.
synapse-relay point between cells.
Electric synapse-When an action potential "jumps" from one cell to the next. takes place in heart and digestive tract
Chemical synapse-a neurotransmitter is sent from one neuron to the next across a synaptic cleft(Space between two neurons), and the neurotransmitters bind to receptor proteins on the other neuron.
Human Nervous system
Cephalization-concentration of the nervous system at the head
Centralization-separate central nervous system and peripheral nervous system
Spinal Cord-bundle of nerve fibers that communicate between the CNS and the body
Cerebrospinal Fluid-cushions the CNS
Meninges-layers of protective connective tissue
Spinal Cord-composed of white matter(Axons w/ myelin sheath), Gray matter(Cerebral Cortex)
See notes for the breakdown of the peripheral nervous system, it's somewhat self explanatory
Frontal Lobe-motor skills-sends commands to skeletal muscle
Parietal Lobe-integrates senses from our entire body, taste, speech
Temporal Lobe-Hearing, Smell
Corpus Callosum-connects the 2 hemispheres so that they can process info
Cerebral cortex-large part of the brain, contains 80% of all brain matter
Brainstem- opening to the brain, regulates sleep and coordinates body movements
Medulla Oblongata-controls involuntary functions
next scribe is Maddy