Neurons; Nervous System Flashcards
What is the cell body?
The part of the neuron that houses the nucleus and most other organelles
What are dendrites?
One of usually numerous, short, highly branched extensions of a neuron that receive signals from other neurons
What is an axon?
A typically long extension, or process, of a neuron that carries nerve impulses away from the cell body toward target cells
What is the axon hillock?
The composed shape of an axon where signals that travel down the axon are generated
What is a synapse?
The junction where a neuron communicates with another cell across a narrow gap via a neurotransmitter or an electrical coupling
What are synaptic terminals?
The part of each axon branch that forms the specialized junction
What are neurotransmitters?
Chemical messengers that pass information from the transmitting neuron to the receiving cell
Information processing by a nervous system occurs in three stages
Sensory input, integration,
and motor output.
Where does integration take place?
Processing center (nervous system)
What system carries information into and out of the central nervous system?
Peripheral nervous system
In the vertebrate central nervous system (CNS), the functions of the ___ and____are tightly coordinated
Brain and spinal cord
What is the function of the brain?
Signaling between neurons functions in learning, feeling emotions, processing sensory information, and generating commands
What is the function of the spinal cord?
Conveys information to and from the brain and generates basic patters of locomotion; produces reflexes
What is the peripheral nervous system (PNS) and what does it do?
Transmits information to and from the CNS and plays a large role in regulating both and animal’s movement and its internal environment
What are the two efferent components of the PNS?
The motor system and the autonomic nervous system
What does the motor system control?
Consists of neurons that carry signals to skeletal muscles
Is that control voluntary or involuntary, or both? What are examples?
Can be voluntary, as when you raise your hand to ask a question, or involuntary, as in the knee-jerk reflex
What does the autonomic nervous system control?
Regulation of smooth and cardiac muscle
Is that control generally voluntary or involuntary?
Involuntary
What does the enteric division of the autonomic nervous system control?
Active in the digestive tract, pancreas, and gallbladder
Which promotes arousal and energy generation (fight-or-flight response)? (of the autonomic system)
Sympathetic division of the autonomic nervous system
Which promotes calming and a return to self maintenance (rest and digest response)?
Parasympathetic division of autonomic nervous system
Do you see why the two systems have largely antagonistic functions?
Different in function but also different in organization and signals released
