COPY: Excitable Tissues and Neurons

• Excitable tissues are characterized by a large resting membrane potential and the ability to respond to stimuli with a series of changes in membrane potential called Action Potentials.
• Excitable tissues include nerves and all types of muscle (smooth, skeletal, and cardiac).
• The neuron is the basic structural unit of the nervous system, consisting of a cell body, cytoplasm, nucleus, and cell organelles, as well as cell processes called axon and dendrites.
• The axon of a neuron conducts impulses away from the cell body, while dendrites increase the surface area of the cell and transmit impulses to the cell body.
• Neurons have 4 types: based on the presence or absence of myelin sheath, and based on function.
• Myelin sheathed nerves are faster and more efficient at conducting impulses, while unmyelinated nerves are slower and less efficient.
• Functional types of nerves include motor, sensory, and autonomic nerves, each with unique characteristics.
• Nerve fibers have several characteristics, including excitability (ability to respond to stimuli), conductivity (ability to transmit impulses), adaptation (decrease impulse discharge with constant stimulus), and non-fatigability (do not tire easily).
• Membrane potential is the electrical potential that exists between the outer and inner surface of the cell membrane of all cells in the body.

Learn about the characteristics of excitable tissues and neurons, including their resting membrane potential and response to stimulation through action potential. Explore the structure of a neuron and its components such as cell body and cell processes like axon and dendrites.