Central Nervous System (CNS)
What two main structures make up the central nervous system?
The brain and spinal cord
What are the two main divisions of the peripheral nervous system?
Autonomic and somatic systems
What type of cell transmits signals throughout the brain and body?
Neurons
What are neurotransmitters?
Chemical messengers that transmit signals between nerve cells
What do psychoactive drugs change in the body?
Behavior and mood by altering neurotransmitter activity
What role does the spinal cord play in the body’s communication?
It serves as the main communication highway between the brain and body.
Which system controls voluntary muscle movements?
The somatic nervous system
What do glial cells provide for neurons?
Structure, insulation, and waste removal
Name the neurotransmitter linked to movement, learning, and pleasure.
Dopamine
What is an agonist drug?
A drug that mimics or enhances neurotransmitters
What happens if the spinal cord is injured?
It can lead to paralysis by disrupting communication from the brain.
What does the autonomic nervous system regulate?
Involuntary processes such as heartbeat and digestion
What is the function of the myelin sheath formed by glial cells?
It speeds up neural transmission.
What hormone regulates the sleep-wake cycle?
Melatonin
Give an example of a stimulant and its effect.
Caffeine; increases alertness and heart rate
The CNS controls both voluntary and involuntary actions. Give one example of each.
What are the two branches of the autonomic nervous system and what do they do?
Sympathetic (activates fight-or-flight); Parasympathetic (calms the body)
What can happen if glial cells are damaged, as in multiple sclerosis?
Neural signal transmission is disrupted.
Which neurotransmitter is the major inhibitory transmitter and helps reduce anxiety?
GABA
What is an example of a depressant and its effect?
Alcohol; slows down brain function and reaction time
Why does damage to the CNS often result in serious impairments?
Because the CNS is responsible for core mental and physical functions throughout the body.
How do the somatic and autonomic systems work together during exercise?
The somatic system moves limbs while the autonomic system regulates heartbeat.
Why are neurons and glial cells considered the building blocks of the nervous system?
Together, they are essential for all communication, behavior, and mental processes.
How are hormones different from neurotransmitters?
Hormones are released by glands and have slower, longer-lasting effects outside the nervous system.
What is the medical risk of prescription opioids?
They can lead to misuse and addiction