Nervous system (1a) Flashcards
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Homeostasis
Stability in the body (maintaining blood pH, heart rate, breathing rate, etc.)
Nervous system
System composed of neurons that sends and receives signals from all over the body (maintains homeostasis)
Endocrine System
System composed of hormones that regulate homeostasis
Central nervous system (CNS)
- made up of the brain and spinal cord
- integrates and processes info
Peripheral nervous system (PNS)
-Sensory receptors and motor defectors branching out into the body
- Brings info back to CNS
Sensory nervous system
Brings sensory information in (from periphery to CNS)
Motor nervous system
Brings motor information out (from CNS to periphery)
Somatic Motor NS (3)
- Voluntary
- skeletal muscle contractions
- Myelinated (Faster)
Autonomic Motor NS (3)
- involuntary
- automatic functions in organs
- Heart beat, breathing rate, digestion, etc
Sympathetic autonomic NS (3)
- Stress response
- Speeds up functions (heart rate, breathing rate)
- Connect from spinal cord
Parasympathetic Autonomic NS (3)
- Peaceful (rest and digest)
- slows functions (heart rate, breathing rate)
- connect from brain
Nerve
Bundle of neurons
Dendrites
Receive stimuli from other neurons
Neuron (2)
- Conducts electrical impulses
- Basic structure and functional unit of nervous system
Soma
Cell body that contains nucleus and cell organelles
Axon
Carries impulse to the correct area of the body
Myelin Sheath
Insulating “marshmallows” along some axons
Myelinated (2)
- Sheathed
- Speeds up impulses
Unmyelinated
no myelin sheath
Axon terminal
Site of transfer of stimulus to other neurons or organs
Glial cells Functions (5)
- Outnumber neurons
- Support neurons (glue)
- Provide nutrients for neurons
- removes waste
- defend against infection
Schwann cells
Glial cells in PNS
oligodendrocytes
Glial Cells in CNS
Nodes of Ranvier
Uncovered spaces between myelinated sections (marshmallow)