Nervous Tissue Flashcards
Provides for generation of nerve impulses (AP) that communicate with and regulate most body tissues
Nervous tissue
Maintaining homeostasis is shared by what two systems?
Nervous system
Endocrine system
How does the nervous system regulate body activities?
Responding rapidly using nerve impulses
How does the endocrine system respond to body activities?
Slowly by use of hormones
Neurology
Deals with normal functioning and disorders of the nervous system
Neurologist
The central nervous system is made up of what?
Brain
Spinal cord
The peripheral nervous system is made up of what?
Cranial nerves
Spinal nerves
Peripheral nerves
What are the functions of the nervous system?
Sensory
Integrative
Motor
How does sensory function in the nervous system?
- Receptors (detect changes inter/external)
- Sensory never cells (neurons) carry sensory info from receptors to the brain and spinal cord
- Sensory neurons are AFFERENT neurons
How does integrative function in the nervous system?
- Analyze and store info
- Make decisions
- Integrative neurons are interneurons, relatively short neurons in the brain, spinal cord, and ganglia that connect nearby neurons
How does motor function in the nervous system?
- Respond to decision
- Motor neurons carry information from brain and spinal cord to effectors (muscles or glands)
- Motor neurons are EFFERENT neurons
What is the general organization of the nervous system?
Somatic
Autonomic
Enteric
Somatic
- Sensation from body walls, limbs, head, special senses
- Motor control of skeletal muscle (voluntary)
Autonomic
- Sensation from internal organs like heart, lungs, bladder
- Motor control of smooth and cardiac muscle, glands (involuntary)
Enteric
- Sensation from gastrointestinal tract
- Motor control of smooth muscle and glands of GI (involuntary)
Consists of all nervous tissue outside the CNS
PNS
- Somatic nervous system (SNS)
- Autonomic nervous system (ANS)
- Enteric nervous system (ENS)
An association (bundle) of neural axons in the peripheral nervous system (Includes dendrites and other tissue)
Nerve
Group of neuronal cell bodies in the PNS (plus associated tissue)
Ganglion
Association (a bundle) of neuronal axons in the CNS
Tract
An ossification (a bundle) of (unmyelinated) nerve cell bodies in the CNS)
Nucleus
Network of nerves
Plexus
Cells that possess electrical excitability (can do an AP)
Neurons
Cells of the nervous system that support, nourish, and protect the neurons
Neuroglia
Are there more or less neuroglia than neurons?
Yes
What are the basic parts of a neuron?
The cell body
Nerve fibers comprising
- an axon
- dendrites
The cytoplasm of an axon
Axoplasm
The plasmalemma of axon
Axolemma
Dendrites (little trees)
- the receiving position of a neuron
- typically short, tapering, highly branched
Axon
- Single axon per neuron
- Propagates impulses to another neuron, muscle, or nerve
- Aprox three feet long in humans
What happens if the axon is cut
The distal fragment dies
What does the axon contain?
Mitochondria
Microtubules
Neurofibrils
Does not contain RER so protein synthesis does not occur in axon
What are neurofibrils and what do they do?
Intermediate filaments
Provide cell shape and support
What are microtubules and what do they do?
Tubulin
Participate in moving material between the cell body and axon