Neurons & Nerve Impulses 3 Flashcards
(32 cards)
What are the two organ systems responsible for coordinating responses to environmental changes in animals?
The endocrine system and the nervous system
Both systems utilize receptors to detect stimuli and effectors to respond.
How do the endocrine and nervous systems differ in terms of communication?
The endocrine system communicates via hormones in the bloodstream, while the nervous system uses electrical messages through neurons.
What is the speed and duration of responses coordinated by the endocrine system?
Slow but long-lived.
What is the speed and duration of responses coordinated by the nervous system?
Fast but short-lived.
What role do sensory receptors play in the nervous system?
They detect stimuli and convey messages to the central nervous system via sensory neurons.
What is the central nervous system (CNS) composed of?
The brain and spinal cord.
What type of neuron connects the CNS to effectors?
Motor neuron.
What are the two divisions of the nervous system?
Central nervous system (CNS) and peripheral nervous system (PNS).
What is an axon?
An extension of a neuron along which an electrical impulse called an action potential passes.
What are nerves?
Bundles of axons.
What is a neural pathway typically composed of?
A sensory neuron, a motor neuron, and one or more interneurons.
What is a reflex arc?
A neural pathway that often involves only one interneuron or no interneurons.
What are reflexes?
Automatic and involuntary responses that enable rapid responses to potentially dangerous stimuli.
What do dendrites do?
They receive signals from other neurons or sensory receptors.
What is the soma also known as?
Cell body.
What is the function of the myelin sheath?
It insulates the axon and speeds up the conduction of action potentials.
What are nodes of Ranvier?
Gaps in the myelin sheath that allow ions to enter and exit the neuron.
What triggers the release of neurotransmitters?
An action potential arriving at axon terminals.
What is a synapse?
The junction between two neurons.
What is the presynaptic neuron?
The sending neuron in a synapse.
What is the postsynaptic neuron?
The receiving neuron in a synapse.
What is synaptic transmission?
The process by which a signal passes from one neuron to another.
What happens to neurotransmitters after they are released?
They bind to receptors in the postsynaptic neuron.
What is signal transduction?
The process by which a chemical signal is transformed into a biological signal.
