- Remember that the hypothalamus controls the autonomic nervous system - Cerebellum does not initiate IT coordinates movement - Choroid plexus makes CSF and secretes ions and nutrients into CFS - Know that that prefrontal association area, primary motor cortex, gustatory cortex, and olfactory cortex are located in the FRONTAL LOBE - Lobotomy: means to REMOVE part of prefrontal cortex - Prefrontal cortex is an example of motor associations area - How signals travel to the brain: primary somatic area, sensory association area, motor association area, primary motor cortex, and out of brain to control movement - Basal Ganglia: involved in the control of motor movement and leads to Parkinson’s disease due to depletion of dopamine (disinhibition) - Ascending and descending tracts are myelinated and found in the WHITE MATTER of the spinal cord - Thalamus - Relay and integrate sensory and motor information - EEG is used in sleep therapy and used to localize seizure activity as in epilepsy … it can tell you where seizures is happening in certain parts of the brain - MRI’s are Imaging of magnetic fields around water and the image is not degraded by bone …. It gives the best, highest resolution images of brain structure - Subarachnoid membrane is loaded with cerebrospinal fluid, a cushion and nutrition for brain, and picks up waste products from brain - Remember that the hopping of an action potential from one node of Ranvier to the next is called: Saltatory conduction - Nodes of Ranvier are NOT the same length as a single Schwann cell - Action potentials occur at the Nodes of Ranvier and are loaded with Na Channels (sodium channels) - Bipolar and pseudounipolar are sensory neurons (afferent) - Pseudounipolar axons split into TWO branches - Anoxic and multipolar neurons are interneurons - Multipolar is an efferent neurons (motor) that leave the spinal cord … connects to muscles and glands - Charge= ions (Na+, K+, Ca++, Cl-). it changes the voltage inside of the cell - Conductance= (1/Resistance). It is defined as the ease of moving ions across membrane - Equilibrium Potential of K+ = -90 mV (this number is when K+ reaches equilibrium) ● can't flow out of cell once it reaches equilibrium point - At the peak of the action potential, The cell is close to the sodium equilibrium potential - If the potassium concentration outside a nerve cell decreases, The potassium equilibrium potential will become more negative - If the concentration of potassium was the same inside and outside of a cell, then the equilibrium potential of potassium would be 0mv (voltage) - The equilibrium potential for Na = +60 mV, for K = -90 mV, and for Cl = -63 mV. If the cell membrane potential is -63 mV, which of the following may be true? Only Na and K channels are open - Equilibrium potential for Na is +60 mV○ This is when Na+ reach equilibrium ○ enters cell - The equilibrium potential for K is -90 mV ● This is when K+ reaches equilibrium ● can't flow out of cell once it reaches equilibrium point - Voltage = the energy to move change - Capacitance (looks like another name for capacity)– Number of ions needed to change membrane voltage - The job of Astrocytes are to: form blood brain barrier, its star shaped, surrounds synapse and clear out excess neurotransmitter from synaptic area - The resting voltage of a neuron is -70mv … inhibiting this is to reduce this number and exciting this is to increase this number Na+ makes this increase K+ and Cl makes this decrease - Inhibition can be described as the following ○ less than -70 mV ○ harder to make cell release transmitter ○ Hyperpolarization ○ bringing in Cl- or K+ - Potassium has the most negative equilibrium potential. - If you know the concentration of sodium inside and outside a nerve cell, then you have enough information to calculate: equilibrium potential for sodium - Hypokalemia makes the potassium equilibrium potential more negative - If the cell membrane potential is -90 mV, then potassium will not flow into or out of the cell - If the cell membrane potential is -100 mV, then potassium will flow into the cell - If the cell membrane potential is -60 mV, then potassium will flow out of the cell - At Resting Membrane Potential (-70 mV), K+ will have bigger conductance (closer to -90 mV) than Na+ (+60 mV) - Electrical-chemical equilibrium relative to K+ is when Chemical force pushed K out down concentration gradient. Electrical force (membrane potential) pulls K back in because the inside of the cell becomes negatively charged when K leaves. Equilibrium achieved when K out = K in. - A Depolarize cell is when ION comes in (so we can assum that hyper is when ions comes out) - Current - rate of movement of charge - Dendrites receive Incoming signals - How do electrical signals travel through a neuron ?? 1. Input comes in through Dendrites as graded potentials 2. Soma 3. Trigger zone 4. Axon5. Synaptic terminal - A graded potential travels along a nerve with fixed amplitude - A trigger zone is where action potential is created if graded potential is at threshold - LOTS OF Na CHANNELS - Glial cells are cells in the nervous system that support, nourish, and protect neurons: Schwann cells, oligodendrocytes, astrocytes - Multiple Sclerosis is a demyelinating disease - What part of the voltage-gated sodium channel protein is responsible for inactivation: The third cytoplasmic loop (s3) - 1. Selectivity filter - P Loop - 2. Voltage sensor - S4 - 3. Inactivation gate - Cytoplasmic loop between domains III and IV (S3 and S4) - S5 and S6 form activation gate - What type of channel transduces sound stimuli into electrical responses in the ear ?: mechanically-gated channels - What channel is positioned adjacent to a docked synaptic vesicle?: Voltage-gated calcium channel - The movement of sodium ions through channels is called Facilitated diffusion - Ionotropic acetylcholine receptors uses facilitated diffusion to move ions across the cell membrane - Carriers do not use diffusion and do not have an equilibrium potential
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