PSYB64H3 Lecture Notes - Lecture 3: Extracellular Fluid, Fluid Compartments, Resting Potential
Document Summary
The structure of neurons: neuron membranes separate intracellular fluid from extracellular fluid, the neural cytoskeleton provides structural support that maintains the shape of the neuron. Membrane is a bi-layer composed largely of phospholipids and other lipids studded with proteins and other large molecules. Ion channels: allow ions to diffuse down concentration gradient, selective permeability to certain ions, don"t require additional energy. Ion pumps: actively move ions against concentration gradient, create ion concentration gradients, require energy. 3 fiber types compose the cytoskeleton of neurons. Structural variations in neurons: unipolar bipolar multipolar, unipolar. Single branch extending from the cell body: bipolar. Two branches extending from the neural cell body: one axon and one dendrite: multipolar. Many branches extending from the cell body; usually one axon and many dendrites. Sensory neurons: specialized to receive information from the outside world. Motor neurons: transmit commands from the cns directly to muscles and glands. Interneurons: act as bridges between the sensory and motor systems.
