Lecture 10: Organization of the Nervous System/Spinal Reflex Connections Flashcards
What is extrinsic control of the nervous system
Maintains homeostasis, glandular activity. Controls movements, perception of environments, transfer of information, storage of information
What is the chemical messenger released in nervous system
Neurotransmitter released into synaptic cleft
What does the specificity of action on the target cell in the NS depend on
Close anatomic relationship between neurons and their target cells
What is the major function of the nervous system
Coordinates rapid, precise responses
What are the 3 anatomical components of the neural circuit
- Inputs (afferent)
- Integrators
- Outputs (efferents)
What are the functional components of the neural circuits
- Sensory inputs (sensory neuron/receptor)
- Computational units (brain and ganglia)
- Output nerves (output to skeletal muscle, smooth muscle or glands)
What are the two divisions of the peripheral NS
Afferent and efferent
What is the afferent division
Carries information from sensory receptors in the skin, skeletal muscles and joints to the CNS via sensory neurons
What is the efferent division
Transmits impulses from the CNS to effector organs (muscles and glands)
What are the two divisions of the efferent division
Somatic and autonomic
What is the somatic nervous system
Fibers of motor neurons that supply skeletal muscle
What is the autonomic nervous system
Fibers that innervate smooth muscle, cardiac muscle, and glands
What does the cotton ball test evaluate
Vision, cranial nerves
What 4 types of movement does the nervous system control
- Voluntary
- Postural
- Rhythmic
- Reflex movement
What type of movement is more complex and may involve learning
Rhythmic
What are the two major cell types that make up NS
Neurons and neuroglia
What cells are excitable and transmit electrical impulses
Neurons
What cells communicate with and support neurons
Neuroglia
What is the soma
Body of the neuron that contains nucleus and most organelles
What are amitotic neurons
neurons do not divide to create more neurons. They lack centrioles an organelle required for cell division
Neurons have a well developed golgi and rough ER thus they are major biosynthetic centers for ___
Neuropeptides
What receives inputs from other neurons, site of synapses
Dendritic spines
What is the primary neuronal output
Axon
What is the axon hillock
Cone shaped area from which the axon arises