nervous system physiology pt 1 Flashcards
What is the function of the nervous system?
- Detects changes, makes decisions, stimulates muscles and glands to respond and maintains homeostasis
What 2 types of cells do neural tissue contain?
- Neurons
- Neuroglia
What is the function of neurons?
- reacts to changes
- send nerve impulses for communication
What is the function of neuroglia?
- surround and support neurons
- nourishes neurons
- help maintain blood-brain barrier
What is the division of the nervous system?
- Central nervous system (CNS)
- Peripheral nervous system (PNS)
What is the CNS?
- brain
- spinal cord
What is the PNS?
- connects CNS to other body parts
- cranial nerves
- spinal nerves
How is the nervous system functionally divided?
- sensory function
- integrative function
- motor function
What is sensory function?
- nervous system receives info
- sensory receptors gather info by detecting changes
- info is carried to the CNS
What is integrative function?
- nervous system coordinates sensory info to create sensations memory, thoughts
- nervous system makes decisions on body’s response to sensory info
What is motor function?
- decisions are acted upon
- impulses are carried to effectors (muscles or glands)
- divisions of motor portion of PNS
What is the somatic nervous system?
- transmits voluntary instructions to skeletal muscles
What is the autonomic nervous system?
- transmits involuntary instructions from the CNS to smooth muscles, cardiac muscle and glands
What are some features of a neuron’s cell body?
- (soma)
- contains nucleus, cytoplasm, organelles, neurofilaments, chromatophilic subtance (Nisse bodies)
- integrate info that comes into the cell body and determines if a single needs to be communicated to another cell
What are some features of a neuron’s dendrite?
- branched receptive surfaces; a neuron many have many
- receives signals from other cells and sends that info to the cell body
What are some features of an axon?
- transmits impulses and releases neurotransmitters to another neuron or effectors (another neuron, muscle cell or a gland cell)
- A neuron many have only 1 axon
- sends the signal from the cell body to another cell
What are the structures of a neuron’s cell body?
- neurofibrils: fine threads that extend into nerve fiber. Provides support for axon hillock and axon
- Chromatophilic substance/Nissl bodies (RER)
What are the structures of a neuron’s dendrite/ axon
- axon hillock
- collaterals
- axon terminal
- synaptic knob
What are the structures of Schwann cells?
- myelin
- myelin sheath
What are the 3 classifications of neurons by structure?
- multipolar neurons
- bipolar neurons
- unipolar neurons
What is the structure of a multipolar neuron?
- 99% of neurons
- many processes
- most neurons of CNS
What is the structure of a bipolar neuron?
- two processes
- eyes, ears, nose
What is the structure of unipolar neurons?
- one process
- cell bodies are in ganglia
- sensory
What are the classifications of neurons by function?
- sensory
- interneurons
- motor