Chapter 45 Lecture Outline

Chapter 45 Lecture Outline - Biology 100 Vandan Desai...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Biology 100 Vandan Desai Chapter 45: The &ervous System (Lecture Outline) -------------------------------------------------------------------------------------------------------------------------- I. Functions of the &ervous System A. Sense and respond to changing conditions B. Awareness of sights , sounds , hunger , fear , and emotion C. Active throughout your life , without rest, until your death II. &euron A. An excitable cell B. Basic unit of communication in nearly all animal nervous system C. Astounding uniformity —neurons function same way in most species III. &eurons Transmit Information Through Electrical Impulses A. Sensory receptors receive information about external environment and body interior i. Sensory cells on the periphery of the body transmit information about the external environment ii. Sensory cells inside the body monitor conditions important in homeostasis B. The pathway of information flow in the nervous system in vertebrates: i. Sensory neurons send information to central nervous system (CNS) ( afferent pathway ) 1. The sensory receptor itself is often a sensory neuron 2. The consists of the brain and spinal cord ii. The integrators ( ) integrate info from many sensory neurons iii. The C&S stimulates a motor neuron , which sends signals to effector cells in glands and muscles ( efferent pathway ) iv. The peripheral nervous system (PNS) consists of all components of the nervous system that are outside the CNS v. A reflex bypasses the brain and travels directly to an effector 1. Reflex makes it possible to have rapid automatic responses 2. A connection is made b/w a sensory neuron and a motor neuron in the spinal cord (so, CNS involved w/o the brain) IV. The Anatomy of a &euron A. Dendrites —fibers, often heavily branched, receive incoming signals B. Cell body command center of neuron; contains the nucleus C. Axons —fibers extending from cell body; contains axon hillock —regions from which action potential is fired i. Input zone —consists of cell body and dendrites ii. Conducting zone —consists of the axon iii. Output zone —consists of axon endings D. Synapse —tiny spaces between adjoining nerve cells ; usually one-way valve; site of signal conversion ( electrical impulse converted to chemical signal ) i. Pre-synaptic cell releases neurotransmitter ii. Post-synaptic cell receives neurotransmitter
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Biology 100 Vandan Desai V. The &euron Membrane A. Thin membrane with similar composition to plasma membrane B. Surrounds the entire neuron C. Lipid bilayer i. Impermeable to ions , polar molecules ii. Results in disequilibrium in charge across membrane D. Embedded proteins allow passage of some materials i. Transport proteins 1. Channel proteins a. Open ( leak ) channels b. Gated channels i. Ligand-gated (open w/ attachment of particular chemical— neurotransmitter ) ii. Voltage-gated (open in presence of particular voltage ) 2. Carrier proteins —change conformation ii. Passive transport 1. Includes
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 03/08/2010 for the course BIOL 100 taught by Professor Staff during the Fall '07 term at UMBC.

Page1 / 7

Chapter 45 Lecture Outline - Biology 100 Vandan Desai...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online