STRUCTURAL AND FUNCTIONAL ORGANIZATION OF NERVOUS TISSUE Flashcards
CNS parts
Brain
Spinal cord
PNS parts
Cranial nerves Spinal nerves Ganglia Enteric Plexuses in small intestine Sensory receptors in the skin
how many pairs of spinal nerves are there
31
Sensory receptors
Monitor changes in the internal and external environment
Ganglia
Small masses of nervous tissue consisting of neuronal cell bodies that are located outside the brain and spinal cord
Example: Dorsal root
ganglion
Enteric Plexus
Extensive network of nerves that are located in the walls of the gastrointestinal tract that help regulate the digestive system.
Sensory function (afferent)
Detect internal and external stimuli and Convey impulses into CNS
Integrative function:
(Information processing)
1) Perception = awareness of sensory input
2) Analyzing and storing information to help lead to appropriate responses
Motor function (Efferent)
Once integration occurs the brain may elicit motor response to muscles or glands (effectors) via cranial and spinal nerves
Neurons vs neuroglia
Neurons: Provide most of the unique functions of the nervous system
Neuroglia: Function to provide support, nourishment, and protection
Parts of a Neuron
Cell body
Dendrites
Axon
Axon terminals
Parts of a Neuron
Axon terminals
Contain synaptic vesicles that can release neurotransmitters
Parts of a Neuron
Axon
Conducts away from cell body toward another neuron, muscle or gland
Emerges at cone-shaped axon hillock
Parts of a Neuron
Dendrites
Highly branched structures that carry impulses to the cell body
Parts of a Neuron
Cell body
Nucleus, cytoplasm with typical organelles
Structural Classes of Neurons
Multipolar
Have several or many dendrites and one axon
Most common type in brain and spinal cord
Structural Classes of Neurons
Bipolar
Have one dendrite and one axon
Example: In retina of eye and inner ear