Chapter 7 The Nervous System
Warm-up Tell me anything you know about the nervous system. What does it consist of? What does it do?
Structures to label Cell body(soma) Axon Hillock Axon Axon Terminal Dendrites Myelin Sheath Nodes of Ranvier
Nervous tissue: neurons Cell body Nucleus Large nucleolus
Nervous tissue: neurons Processes outside cell body Dendrites—conduct impulses toward the cell body Axons—conduct impulses away from the cell body
Functions of the Nervous System
Structural Classification Central nervous system (CNS) Brain Spinal cord Peripheral nervous system (PNS) Nerves outside the brain and spinal cord
Functional Classification Sensory (afferent) division Nerve fibers that carry information to CNS Motor (efferent) division Nerve fibers that carry impulses away from CNS
Functional Classification
Organization of nervous system
Motor (efferent) division Two subdivisions Somatic nervous system = voluntary Autonomic nervous system = involuntary
Nervous Tissue: Glial/Support Cells Support, insulate, and protect neurons
Astrocytes
Astrocytes
Microglia
Microglia
Ependymal cells
Ependymal cells
Oligodendrocytes
Oligodendrocytes
Glial Cells of the PNS Satellite cells Schwann cells
Nervous tissue: neurons Axonal terminals are separated from the next neuron by a gap Synaptic cleft— Synapse—
Multipolar Neurons
Bipolar Neurons
Unipolar Neurons
Patellar Reflex
Patellar Reflex
How fast does your brain react?
How Fast Your Brain Reacts to Stimuli: On the back of lab page you must include: Average of group measurement for visual, auditory and tactile (part 1) Use the formula to calculate your reaction time and average group reaction time for each stimuli Which stimuli did you personally react fastest to? Which stimuli did your group as a whole react fastest to?