ABSTRACT
This chapter discusses the general nature of animal tissues and the continued regulation of processes that maintain the integrity of living tissues. The key properties of excitable tissue, particularly neural and muscular tissues, have been examined. The chapter addresses the organization of the nervous system and shows how stimuli are integrated to elicit particular responses. The nervous system can be divided, both anatomically and functionally, into two major divisions: the central nervous system (CNS) and the peripheral nervous system. Nerves communicate with each other via cell-cell structures known as synapses. In addition to the excitatory synapses that use acetylcholine, there are other synapses that have an inhibitory effect on the potential of the efferent cell. An important inhibitory neurotransmitter is the compound, Y-aminobutyric acid (GABA). Muscle cells, or myocytes, are specialized contractile cells capable of performing mechanical work in response to excitatory events at their surface membrane.
