1. APs and Synaptic Transmission Flashcards
(32 cards)
What is sensory biology?
The study of how organisms perceive and respond to sensory information.
How does a cell detect and transmit sensory information?
Through processes like reception, transduction, and encoding of sensory information.
What is the difference between sensation and perception?
Sensation refers to the detection of sensory stimuli, while perception involves the interpretation of sensory stimuli.
What types of sensory systems will be covered?
Vision, olfaction, taste, touch, hearing, pain.
Mechanotransduction
Process by which cells convert mechanical stimuli into electrical signals.
Role of sensory neurons
Respond to specific classes of stimuli and transmit signals to other neurons. They can be excited or inhibited.
Structure of a typical neuron
Axons, dendrites, soma, axon hillock, and growth cones.
Explain the concept of depolarization and hyperpolarization in sensory neurons
Depolarization makes the neuron more positive than its resting potential, increasing the likelihood of synaptic vesicle release. Hyperpolarization makes the neuron more negative than its resting potential, inhibiting signal transmission.
How do neurons communicate primarily?
Neurons communicate primarily through the release of synaptic vesicles.
What is the “law of specific nerve energies”?
States that the nature of perception is defined by the pathway over which sensory information is carried. Each sensory pathway conveys a specific type of information.
Proposed by Johannes Peter Muller, 1835
What are the four pieces of basic information that all sensory systems must encode?
Modality, location, intensity, and duration or timing.
How is sensory information processed in relay centers?
Sensory information is processed by higher-order neurons acting together. It undergoes filtering, processing, and integration, ultimately leading to perception.
Explain the basis for APs
APs are based on changes in membrane potential, specifically depolarization and hyperpolarization.
What is the role of Na+/K+ ATPase in neuronal signaling?
Na+/K+ ATPase actively pumps sodium ions out of the cell and potassium ions into the cell, establishing essential ionic gradients for neuronal signaling and cellular homeostasis.
What is the role of ion channels in initiating APs?
Ion channels are essential for the rapid changes in membrane potential that lead to APs.
Explain the role of ion gradients in establishing a resting potential
Ion gradients are critical for maintaining the slightly negative resting potential of neurons.
What happens at the steady state in terms of ion currents?
The net inward current equals the net outward current, primarily driven by potassium ions.
What are the key ions involved in establishing the resting potential of a neuron?
Na+ and K+
What role do Na⁺ and K⁺ ions play in AP generation?
Na+ ions contribute to depolarization during AP initiation, while K+ ions play a role in repolarization and hyperpolarization.
How does the concept of synaptic vesicle release relate to neuronal communication?
Neurons primarily communicate through the release of synaptic vesicles, which contain neurotransmitters for signal transmission.
Explain the importance of selective ion channels in neuronal signaling
Allow specific ions to pass through the cell membrane, enabling changes in membrane potential essential for AP generation.
Why is it essential for sensory neurons to be excited or inhibited?
Both excitation and inhibition are used to control the flow of sensory information and modulate responses to different stimuli.
What is the function of a growth cone in a neuron?
Facilitates the extension and guidance of an axon.
What is the role of delayed electrical signals in sensory transmission?
Convey ‘sense’ energies to the brain.
-Delayed electrical signals convey sensory information from peripheral receptors to the central nervous system, allowing the brain to process and perceive external stimuli.
-The time delay is essential for sensory perception. (we live in the past!**)
