BIO 3342 Lecture Notes - Lecture 34: Elastin, Urinary System, Neuroglia
Document Summary
Functions of epithelia: protection of underlying tissues, secretion, absorption, diffusion, filtration, sensory reception. Special characteristics of connective tissues: relatively few cells, lots of extracellular matrix, extracellular matrix composed of ground substance & fibers : produced by cells of connective tissue, embryonic origin : all originate from the embryonic tissue (mesenchyme) Skeletal muscle tissue : pulls on bones to cause body movements: long, large cylinders that contains many nuclei, striated appearance. Cardiac muscle tissue : occurs in walls of heart, propels blood through the blood vessels: striated, uni-nucleated, branches at intercalated discs (type of cellular junction) Smooth muscle tissue : no visible striations, elongated with tapered ends, centrally located nucleus. Neurons : highly specialized nerve cells that generate and conduct electrical impulses: axon : process that generates nerve impulses and transmits them away from the cell body. Dendrites : receptive region of the neuron, transmit signals toward the cell body. Neuroglia : nonconducting cells that nourish, insulate, and protect the neurons.
