Module 6: Interactive Physiology: Nervous System

Module 6:  Interactive Physiology:  Nervous SystemNervous System I:  Anatomy ReviewNeurons can communicate because of their anatomical design and because they are _________________________. Neurons communicate with other neurons, muscles and ____________________________________. ______________________________ receive signals from other neurons and send them toward the axon. The conducting region of the neuron is the ___________________________________. What is transmitted the length of the axon to a target cell is an _________________________________________. Axons vary in size from 1 mm to over 1 __________________________________. The junction between neurons where one neuron communicates with another neuron is a ____________________. Action potentials are generated at the ______________________________________________ . Action potentials are conducted along the axon to the end of the axon called the _____________________________. Axons in the PNS are myelinated by ________________________________ cells. Gaps in the myelin sheath (between Schwann cells) are called __________________________________________. The receptive and integrative regions of the neuron are the dendrites and the _______________________________.  Nervous System I:  Ion ChannelsIon channels are selective based on their size and ____________________________. Non-gated channels are also called ______________________________ channels. In terms of charge, the outside of a neuron’s membrane is slightly __________________________. The difference in charge across the membrane produces a voltage called the ______________________ potential. Voltage gated channels open and close during an _______________________________________. Neurotransmitter binds to receptors on ________________________________ channels and causes them to open. Voltage gated channels are found on the axon hillock and all along the _____________________________. Non-gated channels are responsible for the _______________________________________ potential. Chemically gated channels are responsible for ___________________________________ potentials. Voltage gated channels are responsible for ____________________________________ potentials.  Nervous System I:  The Membrane PotentialNa+ is more abundant ______________________________ cells and is balanced in charge by Cl-. K+ is more abundant ______________________________ cells and is balanced in charge by intracellular proteins. Neurons are selectively permeable to Na+, Cl- and ________________________________. The permeability of a cell for a given ion _____________________ when gated channels for that ion are opened. Ions diffuse _______________________________ their concentration gradients. Resting membranes are very permeable to ______________ and only slightly permeable to ______________. More K+ leaks out of the cell than Na+ leaks in causing the inside of the membrane to be The resting membrane potential for neurons is _________________________ mv. The Na+-K+ pump keeps pumping _______­­­________out of the cell in exchange for ________________ into the cell. Since the Na+-K+ pump moves ions against their electrochemical gradients it requires ________________________.  Nervous System I:  The Action PotentialNerve impulses are the signals between neurons. They are also called ___________________________________. Action potentials result from a rapid change in permeability of the neuron membrane to _________ and _________. The stimulus must reach ____________________ for an action potential to be generated. Action potentials are generated at the ____________________________________________. The depolarization phase of an AP is caused by voltage gated channels opening and _________ rushing into the cell. The depolarization phase ends with the inactivation of voltage gated __________________ channels. As voltage gate Na+ channels become inactivated, voltage gated ____________ channels open. As K+ moves out of the cell this causes the _____________________________________. When an excess of K+ moves out of the cell this causes a ______________________________________. The _________________ refractory period is the time during and action potential when another cannot be generated. A stronger than threshold stimulus can generate another AP during the ____________________ refractory period. Conduction velocity is the speed at which APs are ________________________________________. APs travel faster on axons with greater __________________________ and axons that are ____________________. APs in myelinated axons jump from node to node. This is fast and is called _________________________________. Nervous System II:  Anatomy ReviewNeurons form synapses with other ______________________________ glands and muscles. Skeletal muscle is stimulated by neurons of the ________________________________ nervous system. Cardiac muscle, smooth muscle and glands are stimulated by neurons of the __________________ nervous system. Neurons can excite or _______________________________ other neurons. The most common type of synapse is the ____________________________ synapse. The signal transmitted from one neuron to another is by way of __________________________________. The neuron conducting an action potential toward the synapse is called the _______________________ neuron. The neuron receiving the signal is called the __________________________________ neuron.  Nervous System II:  Ion Channels Neurotransmitters bind to a ___________________________ on the postsynaptic neuron. An EPSP is produced when the movement of ions makes the inside of the cell membrane more ________________. An IPSP is produced when the movement of ions makes the inside of the cell membrane more _________________. EPSPs depolarize the neuron by allowing _______________ to flood into the cell. IPSPs hyperpolarize the neuron by allowing _______________ to flood into the cell. EPSPs promote _______________________ and IPSPs inhibit ___________________________ from happening.  Nervous System II:  Synaptic Potentials and Cellular IntegrationSynaptic potentials are small compared to _________________________________________. The amplitude of synaptic potential depends on the influx of _________________ into the presynaptic terminal. The greater the influx of Ca++, the greater the release of _________________ and the greater the synaptic potential. Presynaptic inhibition can result due to an ____________________ synapse. This decreases the amplitude of the synaptic potential Because synaptic potentials vary in amplitude, they are said to be _______________________ potentials. Synaptic potentials travel only a small distance because they __________ as they move along the neuron membrane. Temporal summation occurs because a series of EPSPs can _________________________ at the same synapse. ____________________ summation occurs because EPSPs at multiple synapses can summate. Many EPSPs are required to ________________________________ a neuron to threshold. IPSPs can also summate and have an __________________________________ effect. IPSPs reduce the magnitude of _________________________________ making it harder to reach threshold.