Preview

Nervous and Digestive System

Good Essays
Open Document
Open Document
1285 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Nervous and Digestive System
Cerebellum – coordination of movement and aspects of motor learning
Cerebrum – conscious activity including perception, emotion, thought, and planning
Thalamus – Brain’s switchboard – filters and then relays information to various brain regions
Medulla – vital reflexes as heart beat and respiration
Brainstem – medulla, pons, and midbrain (involuntary responses) and relays information from spine to upper brain
Hypothalamus– involved in regulating activities internal organs, monitoring information from the autonomic nervous system

Basic functional cell of nervous system
Transmits impulses (up to 250 mph)

Parts of a Neuron
Dendrite – receive stimulus and carries it impulses toward the cell body
Cell Body with nucleus – nucleus & most of cytoplasm
Axon – fiber which carries impulses away from cell body
Schwann Cells- cells which produce myelin or fat layer in the Peripheral Nervous System
Myelin sheath – dense lipid layer which insulates the axon – makes the axon look gray
Node of Ranvier – gaps or nodes in the myelin sheath
Impulses travel from dendrite to cell body to axon
Neurotransmitters – Chemicals in the junction which allow impulses to be started in the second neuron

A stimulus is a change in the environment with sufficient strength to initiate a response.
Excitability is the ability of a neuron to respond to the stimulus and convert it into a nerve impulse
All of Nothing Rule – The stimulus is either strong enough to start and impulse or nothing happens
Impulses are always the same strength along a given neuron and they are self-propagation – once it starts it continues to the end of the neuron in only one direction- from dendrite to cell body to axon
The nerve impulse causes a movement of ions across the cell membrane of the nerve cell.
Epilepsy - common and diverse set of chronic neurological disorders characterized by seizures.
Seizures - the physical findings or changes in behavior that occur after an episode of

You May Also Find These Documents Helpful

  • Powerful Essays

    NeuroPhsioEX 3

    • 592 Words
    • 3 Pages

    Electrical, mechanical, thermal, and chemical stimulation are all capable of generating an action potential in a nerve.…

    • 592 Words
    • 3 Pages
    Powerful Essays
  • Good Essays

    Nerve fibers with many Schwann cells forming a thick myelin sheath are called myelinated fibers, or gray fibers.…

    • 10962 Words
    • 62 Pages
    Good Essays
  • Powerful Essays

    3. The axon terminal is the nerve ending. The nodes speed up the message. The myelin sheath is an insulating membrane. The axon carries impulses away from the cell body. The cell body is the largest part of a typical neuron. The dendrites carry impulses from the environment or from other neurons toward the cell body. The nucleus is the control center of the cell.…

    • 1017 Words
    • 5 Pages
    Powerful Essays
  • Better Essays

    The nerve impulse caused by a charge in the electrical charge across the cell membrane of the axon. When the neuron "fires", this charge…

    • 889 Words
    • 4 Pages
    Better Essays
  • Powerful Essays

    Nervous impulses are electrical signals that travel along neurons. The electrical signals cannot travel from one neuron to the next directly. The signal crosses the gap, called a synapse, between cells in chemical form. One neuron releases chemicals in response to an action potential (nerve impulse). The chemicals travel across the synapse and stimulate an action potential in the next neuron. These chemicals are known as neurotransmitters. Neurotransmitters are stored in vesicles within a neuron and released through the…

    • 830 Words
    • 4 Pages
    Powerful Essays
  • Better Essays

    Notes for Module 7 DBA

    • 1950 Words
    • 7 Pages

    The axon is a long, branching extension that carries impulses away from the neuron's cell body to other neurons.…

    • 1950 Words
    • 7 Pages
    Better Essays
  • Good Essays

    at its dendrites, passes the signals down the axon, into the axon terminals, and into the synapses. The…

    • 710 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Thinking Assignment 1

    • 551 Words
    • 3 Pages

    Neurotransmitters: A chemical released by the sending neuron that activates the receptors on the receiving neuron.…

    • 551 Words
    • 3 Pages
    Good Essays
  • Powerful Essays

    Action Potential – The nerve impulse that travels down the axon and triggers the release of neurotransmitters into a synapse.…

    • 2465 Words
    • 10 Pages
    Powerful Essays
  • Good Essays

    Sensation is the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.…

    • 963 Words
    • 4 Pages
    Good Essays
  • Good Essays

    vii. Electrical signal along a nerve cell triggers a chemical release across a synapse to trigger response…

    • 1459 Words
    • 6 Pages
    Good Essays
  • Good Essays

    Myelin sheath is a fatty covering around long axons that protect it and help increase the speed of nerve impulse transmission. In the CNS the oligodendrocytes form the myelin sheath, while in the PNS Schwann cells form it. Schwann cells create gaps, known as nodes of Ranvier, while oligodendrocytes completely cover the axon.…

    • 326 Words
    • 2 Pages
    Good Essays
  • Good Essays

    Action Potentials

    • 408 Words
    • 2 Pages

    The absolute refractory period places a limit on the rate at which a neuron can conduct impulses, and the relative refractory period permits variation in the rate at which a neuron conducts impulses. Such variation is important because…

    • 408 Words
    • 2 Pages
    Good Essays
  • Good Essays

    Figure 1 showed that the elicited compound nerve action potentials (CAPs) of the Lithobates pipiens nerve showed progressive increase in amplitude with each increase in stimulus intensity going from 20mv to 40 mv to 60mv etc. demonstrating that not all neurons have reached their limits aka threshold. We could say that the amplitude for each neuron doesn't increase with the stimulus intensity but increases because more neutrons are firing and reaching their threshold at each point. Figure 2 also showed that the amplitude decreased in response to stimulus interval. The amplitude showed a significant decrease and complete disappearance at 2.5ms (figure 2) that’s the end of relative refractory period. In relative refractory period, there can be few Na+ channel open but not enough to reach the threshold and cause all or nothing response. When the amplitude reached zero, that would be the absolute refractory period. In this period there can be no Na+ channel open and it can not be stimulated in this period. Table 1 the determination of conduction velocity of Lithobates pipiens nerve was found to be 4.75 m/s which is pretty low range, could be due to an error. Neurons give off an electrical signal that allow neurons to communicate with each other to deliver information very quickly. The point of this experiment was to look at the relationship between the levels of…

    • 917 Words
    • 4 Pages
    Good Essays
  • Good Essays

    Sense Organs

    • 2656 Words
    • 11 Pages

    * Change mechanical, electrical, thermal, chemical, or radiant energy into nerve impulses in sensory neurons…

    • 2656 Words
    • 11 Pages
    Good Essays