Nervous Tissue Flashcards
Nervous Tissue
Communication, information gathering, integration, control = rapid response!
How is nervous tissue excitable?
Membrane potentials
Where does nervous tissue originate?
Neuroectodermal origin
How is nervous tissue similar to muscle tissue?
- Can be both a tissue and a cell
- Neuron = cell (axons = nerve fibers)
- Tissue = neurons + supportive tissue
Components of nervous tissue
- Endoneurium
- Perineurium
- Epineurium
Central Nervous System
- Brain: Cerebrum, Cerebellum, Brain Stem
- Spinal cord
Peripheral Nervous System
- Cranial and spinal nerves
- Ganglion (-a)
Neurons
- Sensory (afferent)
- Motor (efferent)
- Interneurons (most)
Neuron composition
- Cell body (afferent)
- Dendrites (afferent)
- Axon (efferent)
- Synaptic junction (efferent)
Supporting cells
- Schwann cells
- Satellite cells
- Glial cells
Types of Neurons
- Multipolar
- Bipolar
- Unipolar (aka psudounipolar)
Can you see nerve cells histologically?
No
Somatic
- Sensory
- Motor
Autonomic
Visceral, sympathetic, parasympathetic
- Smooth muscle (hormonal too)
- Cardiac stimulation (+/-)
- Glandular epithelium
How do you tell somatic cells from autonomic?
You cannot tell them apart histologically, but can determine which is which based on the location
Nerve cell body components
Typical of protein-producing cells
- Nucleus/nucleolus
- RER
- Nissl bodies (substance)
- Mitochondria
- Golgi
Axonal hillock
Widened trunk leading out to a neuron
- where nerve impulses originate
- where depolarization occurs
Can you see nerve cell bodies histologically?
Yes
Processes
Dendrites –> receptors
- Environment
- Other neurons
Axons –> effectors
- Other neurons
- Effector structures
Axonal transport
Neurotransmitters
- Slow vs. rapid transport