1 / 11

Central Nervous System

This overview discusses the protective structures of the central nervous system, highlighting the meninges and spinal cord. The meninges consist of three layers: the dura mater (outer), arachnoid mater (middle), and pia mater (inner). The spinal cord, with its 31 segments, is responsible for conducting nerve impulses and serves as a center for spinal reflexes. The overview also explores the nature of reflexes, including inborn and learned reflexes, and the components of a reflex arc, which enables rapid responses to stimuli.

cady
Télécharger la présentation

Central Nervous System

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. Central Nervous System Ch. 13-1

  2. Protective Structures • Bone • Meninges • Cerebro-spinal fluid

  3. Meninges • Three connective tissue coverings that encircle the spinal cord and brain • Dura mater – most superficial • Arachnoid mater – looks like spider web • Pia mater – thin, transparent, adheres to surface of brain and spinal cord

  4. Meninges

  5. Meninges

  6. Spinal Cord • Has 31 segments, each with a pair of spinal nerves • 2 main enlargements • Cervical – supplies nerves to upper limbs • Lumbar – supplies nerves to lower limbs • Function • Conducting nerve impulses • Serves as a center for spinal reflexes

  7. Spinal Cord

  8. Spinal Cord • Ascending – impulses travel to the brain (sensory) • Descending – impulses travel to the muscles (motor)

  9. Reflexes • Fast, automatic, unplanned sequence of actions that occurs in response to a particular stimulus • Some are inborn • Moving hand from hot surface • Some are learned or acquired • Slamming on breaks while driving

  10. Reflexes • Spinal reflex • Integration occurs in spinal cord • Knee-jerk reflex • Cranial reflex • Integration occurs in brain stem • Tracking movements of the eyes while reading • Somatic reflex • Involve contraction of skeletal muscles • Autonomic reflex • Not consciously perceived

  11. Reflex Arc • Pathway followed by a nerve impulse that produces a reflex • 5 components • Sensory receptor • Sensory neuron • Integrating center • Motor neuron • Effector

More Related