1 / 24

2 .2

2 .2 . THE NERVOUS SYSTEM. The body’s communication systems help maintain homeostasis. A stimulus causes a response. Responses can be chemical, cellular, or behavioral. The nervous system responds to stimuli. The nervous system controls thoughts, movement, and emotion. spinal chord.

jadzia
Download Presentation

2 .2

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. 2.2 THE NERVOUS SYSTEM

  2. The body’s communication systems help maintain homeostasis. • A stimulus causes a response. • Responses can be chemical, cellular, or behavioral. • The nervous system responds to stimuli.

  3. The nervous system controls thoughts, movement, and emotion.

  4. spinal chord nerves • The nervous system works quickly, using chemical and electrical signals. • interconnected network of cells • signals move through cells • divided into central nervous system (CNS) and peripheral nervous system (PNS)

  5. The nervous system’s two parts work together. • The CNS includes the brain, brain stem, and spinal cord. • The PNS includes four systems of nerves.

  6. The CNS processes information. • The brain has three parts. • cerebrum controls thought, movement, emotion

  7. Lobes of the Brain There is a fifth lobe, known as the limbic lobe, that is responsible for emotions

  8. midbrain Brainstem pons medulla oblongata The CNS processes information. • The brain has three parts. • cerebrum controls thought, movement, emotion • cerebellum allows for balance • brain stem (reptilian brain) controls basic life functions

  9. midbrain pons medulla oblongata • midbrain controls some reflexes • pons regulates breathing • medulla oblongata controls heart function, swallowing, coughing • The brain stem has three parts.

  10. interneuron motor neurons sensory neuron • sensory neuron sends impulse to spinal cord • spinal cord directs impulse to motor neuron • does not involve the brain • See simulation with online textbook • The spinal cord controls reflexes.

  11. The PNS gathers and transmits information • links the CNS to muscles and other organs. • The somatic nervous system regulates voluntary movements.

  12. The PNS gathers and transmits information • The autonomic nervous system controls involuntary, functions • sympathetic nervous system: • “fight vs. flight” • Involved in all internal adjustments that prepares the body for action or increased levels of stress. • parasympathetic nervous system: • sends impulses that return a body to “normal” functioning after a period of stress is over, • conserves energy

  13. Fine adjustments made so glands and organs are functioning at levels appropriate to a body at a particular time:

  14. Sensory receptor generates impulse. • PNS passes impulse to CNS. • CNS interprets impulse. • CNS passes impulse to PNS. • PNS stimulates a response. • The CNS and PNS pass signals between one another.

  15. Sensory Input triggered by stimuli • conduction of signals to processing center • Integration • interpretation of sensory signals within processing centers • Motor output • conduction of signals to effector cells (i.e. muscles, gland cells) Basic Organization sensory receptor (sensory input)  integration  (motor output)  effector

  16. Nerves • Nerves, which carry the electrical impulses to various parts of the nervous system, are made up of a bundles of cells, known as neurons

  17. Cell body 1 Neurons are highly specialized cells. • A neuron has 3 main parts. • cell body contains nucleus and organelles

  18. 2 dendrites Neurons are highly specialized cells. • A neuron has three parts. • cell body has nucleus and organelles • dendrites receive impulses

  19. 3 axon Neurons are highly specialized cells. • A neuron has three parts. • cell body has nucleus and organelles • dendrites receive impulses • axoncarries (transmits) impulses

  20. Schwann cell makes up the myelin sheath, which insulates the axon • Neurons have other structures to transmit signals.

  21. Schwann cell makes up the myelin sheath, which insulates the axon • Nodes of Ranvier – the gaps between the myelin sheath that speed up the process of transmitting impulses. • Neurons have other structures to transmit signals.

  22. Schwann cell makes up the myelin sheath, which insulates the axon • Nodes of Ranvier – the gaps between the myelin sheath that speed up the process of transmitting impulses. • Neurons have other structures to transmit signals. • Axon terminal – part through which the impulse leaves. axon terminal

  23. synapse • Schwann cell makes up the myelin sheath, which insulates the axon • Nodes of Ranvier – the gaps between the myelin sheath that speed up the process of transmitting impulses. • Neurons have other structures to transmit signals. • Axon terminal – part through which the impulse leaves. • synapse gap between the neuron and the next cell.

  24. Types of Neurons • Sensory Neuron: detect stimuli and transmit signals to the brain and the spinal cord, which are both made up of interneurons. • Interneurons: receive signals from sensory neurons and relay them within the brain and the spinal cord. Process information and pass signals to motor neurons. • Motor neurons: pass messages from the NS to other tissues in the body, such as muscles

More Related