Nervous Sytem Overview
What are the two main parts of the nervous system?
The central nervous system (CNS) and peripheral nervous system (PNS)
What is the basic functional unit of the nervous system?
The neuron
What is the name of the protective layers around the brain and spinal cord?
The meninges
What is the term for the electrical signal that travels along a neuron?
An action potential
Which part of the nervous system controls voluntary actions?
The somatic nervous system
What is the name of the supporting cells in nervous tissue?
Neuroglia (or glial cells)
What fluid cushions the brain and spinal cord?
Cerebrospinal fluid (CSF)
What ions are involved in generating an action potential?
Sodium (Na⁺) and potassium (K⁺) ions
What is the role of the autonomic nervous system?
It regulates involuntary functions, such as heart rate, digestion, and respiratory rate.
What is the role of myelin in nervous tissue?
It insulates axons and speeds up nerve impulse transmission.
What is the purpose of the blood-brain barrier?
To protect the brain by preventing harmful substances from entering its tissues.
What happens during depolarization of a neuron?
Sodium ions rush into the neuron, making the inside more positive.
What is the main function of the Central Nervous System?
To process and interpret sensory information and send out responses.
Name the three main parts of a neuron.
The cell body, axon, and dendrites
Name the three layers of meninges from outermost to innermost
Dura mater, arachnoid mater, and pia mater
What is the role of neurotransmitters?
They transmit signals across a synapse from one neuron to another
Which part of the nervous system is responsible for the "fight or flight" response?
The sympathetic division of the autonomic nervous system.
What type of neurons carry signals from sensory organs to the CNS?
Sensory neurons (or afferent neurons)
What structure protects the spinal cord from physical damage?
The vertebrae (spinal column)
What is the refractory period in nerve impulses?
The brief time after an action potential when a neuron cannot fire another impulse.