Environment: The Human Nervous System Flashcards
What is the nervous system?
A complex network of neurons that carry messages between the brain, spinal cord, and body
What are the two main parts of the nervous system?
The central nervous system (CNS) and the peripheral nervous system (PNS)
What does the central nervous system (CNS) consist of?
The brain and spinal cord
What is the function of the CNS?
It processes information and controls body and mind functions
What does the peripheral nervous system (PNS) do?
It connects the CNS to limbs and organs
What are the two divisions of the PNS?
The somatic nervous system (voluntary actions) and the autonomic nervous system (involuntary actions)
Give an example of an action controlled by the somatic nervous system
Moving your arm to pick up an object
Give an example of an action controlled by the autonomic nervous system
Heartbeat or digestion
What are neurons?
Specialized cells that transmit electrical signals (nerve impulses)
Name the three main types of neurons
Sensory neurons, motor neurons, and relay neurons
What do the sensory neurons do?
Carry signals from sensory receptors to the CNS
What do motor neurons do?
Transmit impulses from the CNS to effectors (muscles or glands)
What do the relay neurons do?
Connect the sensory and motor neurons within the CNS
What is a synapse?
A junction where two neurons meet and transmit signals using neurotransmitters
What is the function of dendrites?
They receive signals from other neurons
What is the function of an axon?
It transmits nerve impulses away from the cell body
What is a reflex arc?
The pathway followed by nerve impulses in a reflex action
List the stages of a reflex arc
- Stimulus
- Sensory in neuron
- Relay neuron (CNS)
- Motor neuron
- Effector response
What are reflex actions?
Rapid, involuntary responses to stimuli that help prevent injury
Give an example of a reflex action
Pulling your hand away from a hot surface
What are the two systems that coordinate the body?
The nervous system (fast responses) and the endocrine system (slower, long-term responses)
What is the largest part of the brain and what does it control?
The cerebrum, which controls intelligence, creativity, emotions, and sensory processing
What does the cerebellum do?
It coordinate voluntary movements, maintains posture, and balance
What vital functions does the medulla oblongata control?
Heartbeat, breathing, and digestion
What is the function of the hypothalamus?
It regulates body temperature, hunger, thirst, and some behaviors
