structure of the NS Flashcards
(17 cards)
What is the main function of the nervous system?
To interact with the environment by registering signals, processing them, and generating appropriate responses.
Q: What are the three basic steps required for behavior?
A: 1) Register information, 2) Process it internally, 3) Generate a response.
Q: What defines behavior in organisms?
A: An internally coordinated response to internal or external stimuli.
Q: Which multicellular animals lack a nervous system?
sponges
what are neurons
electrochemically active cells specialised for communication
Q: What is the simplest form of nervous system organization?
A: Uncentralized, like in the hydra.
Q: Which animals have centralized nervous systems with separate CNS and PNS?
flatworms , leeches, insects
what does the CNS include in vertebrates
the brain and spinal cord
what does the PNS do
connect the CNS to the rest of the body
what are the 3 processes of the nervous system communication
detect sensory signals , interpret them and send motor signals
where do sensory signals enter and leave the CNS
spinal cord
what is a monosynaptic reflex
a reflex where a sensory neuron directly activates a motor neuron
Q: What is the purpose of monosynaptic reflexes?
A: To resist quick muscle stretching and stabilize movement.
polysynaptic reflex arc
a reflex involving one or more interneurons between sensory and motor neurons
what is a synapse
the structural and functional connection between a neuron and another cell
what is a central pattern generator (CPG)
a neural icrucit in the spinal cord that generates rhythmic movements like walking
Q: Can central pattern generators initiate movement on their own?
A: No, they require a stimulus to activate the pattern.
