from nerves cells 1 Flashcards
What is the primary role of the nervous system?
o enable rapid and precise data transfer, allowing animals to analyze and respond to internal and external environments.
Why did the nervous system evolve?
In response to movement, as hormonal signals were too slow for rapid coordination.
How many neurons and glial cells are in the human brain?
Approximately 10¹¹ neurons and 10¹² glial cells.
What are the main parts of a neuron?
Cell body (soma), dendrites, and axon.
What is the primary function of the neuron’s cell body?
Houses the nucleus and organelles, performing energy production and protein synthesis.
What is the role of dendrites in a neuron?
They receive incoming signals and increase surface area for connections.
What is the purpose of the axon and its myelin sheath?
The axon transmits signals, and the myelin sheath insulates to increase signal speed.
What are the Nodes of Ranvier?
Gaps in the myelin sheath that facilitate rapid signal propagation.
What happens at a synapse?
It is the site where neurons communicate, often using neurotransmitters across a synaptic cleft.
What is an action potential?
The electrical signal generated at the axon hillock that travels along the axon.
The electrical signal generated at the axon hillock that travels along the axon.
Amino acids (e.g., Glutamate), Amines (e.g., Dopamine), and Peptides (e.g., Substance P).
How does a neurotransmitter’s effect depend on receptor subtypes?
The same neurotransmitter can be excitatory or inhibitory based on the receptor it binds to.
What is the difference between convergence and divergence in neuronal networks?
Convergence: Multiple neurons synapse onto one.
Divergence: One neuron synapses onto many.
What are the three main components of a nervous system network?
Sensor, integrator, and effector.
Why is the nervous system critical for movement?
It provides rapid, precise information transfer, essential for responding to environmental changes.
