Chapter 12 Flashcards
Nervous System
Includes brain, spinal cord, and nerves.
Neurons
Cells for intercellular communication in nervous tissue.
Neuroglia
Supportive cells essential for neuron function.
Central Nervous System (CNS)
Brain and spinal cord; processes sensory data.
Peripheral Nervous System (PNS)
Nervous tissue outside CNS; connects to organs.
Enteric Nervous System (ENS)
Nervous system in digestive tract; 100 million neurons.
Afferent Division
Carries sensory information to the CNS.
Efferent Division
Carries motor commands away from the CNS.
Effectors
Target organs responding to motor commands.
Somatic Nervous System (SNS)
Controls voluntary and involuntary skeletal muscle.
Autonomic Nervous System (ANS)
Controls subconscious actions like heart rate.
Sympathetic Division
Stimulates ‘fight or flight’ responses.
Parasympathetic Division
Promotes ‘rest and digest’ functions.
Dendrites
: Short branches receiving signals from other neurons.
Axon
Long projection carrying signals away from cell body.
Axonal Transport
Movement of materials between cell body and axon terminals.
Anaxonic Neurons
Small neurons with similar processes; found in brain.
Bipolar Neurons
One dendrite and one axon; rare in special senses.
Unipolar Neurons
Fused axon and dendrites; most sensory neurons.
Multipolar Neurons
One axon and multiple dendrites; common in CNS.
Resting Membrane Potential
Voltage difference across a neuron’s membrane at rest.
Action Potential
Rapid change in membrane potential; signal propagation.
Synapse
Junction between neurons for signal transmission.
Neurotransmitters
Chemical messengers affecting postsynaptic membranes.