Nervous Tissue !
Anatomy & Physiology
- Overall Purpose of the Nervous System !
• To keep controlled conditions within limits that maintain life health and homeostasis !
- Regulates body activities by responding via nerve impulses, works with the endocrine system which responds by releasing hormones !
• Responsible for our behavior, memories, and movements !
• Neurology : branch of medicine that deals with normal functioning and disorders of the nervous system !
- Functions of Nervous System !
• Sensory : sensory receptors detect internal and external stimuli and carry information to brain and spinal cord !
• Integrative : processing of sensory information and determining response !
• Motor : responding to information !
- Divisions of the Nervous System !
• Central Nervous System (CNS) !
- Brain, spinal cord !
• Peripheral Nervous System (PNS) !
- Sensory (afferent) neurons carries signals toward the CNS !
- Motor (efferent) neurons carries singles away from the CNS to effectors !
- Peripheral Nervous System !
• Somatic Nervous System : motor neurons transmit signals to skeletal muscles !
- Effector - skeletal muscle !
• Autonomic Nervous System : effectors are smooth muscle, cardiac muscle, glands, adipose tissue !
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Thursday, January 30, 2014
- Two divisions : sympathetic (Fight-or-Flight) and parasympathetic (Rest-andDigest) !
• Enteric Nervous System : effectors are smooth muscle, glands, endocrine cells of the the GI tract !
- Enteric NS : Brain of the Gut !
• Between the circular and longitudinal smooth muscle layers of the muscularis !
• 100 million neurons arranged into two plexus extending from the esophagus to the anus !
• Sensory neurons : stretch receptors, chemoreceptors !
• Motor Neurons : movement of food, secretion of gastric juice, hormones from cells in the epithelium that line the GI tract !
- Types of Cells !
• Neuroglia : connective tissue cells in