Questions and Answers
Which criterion is used to functionally classify neurons?
The direction in which the nerve impulse travels relative to the central nervous system.
During depolarization, which gradient(s) move(s) Na+ into the cell?
Both the electrical and chemical gradients.
The membranes of neurons at rest are very permeable to _____ but only slightly permeable to _____.
K+; Na+
In which direction is each ion pumped by the Na+-K+ pump?
Signup and view all the answers
The concentrations of which two ions are highest outside the cell?
Signup and view all the answers
Why are some forms of MS characterized by periods of remission and exacerbation?
Signup and view all the answers
Which of the following are bundles of neurofilaments important in maintaining the shape and integrity of neurons?
Signup and view all the answers
Which of the following is NOT a functional classification of neurons?
Signup and view all the answers
Which type of glial cell monitors the health of neurons and can transform into macrophages?
Signup and view all the answers
Why does injection of a local anesthetic into a finger cause a loss of sensation of touch?
Signup and view all the answers
The period after an initial stimulus when a neuron is not sensitive to another stimulus is the?
Signup and view all the answers
Which best characterizes depolarization?
Signup and view all the answers
Which statement best describes exocytosis?
Signup and view all the answers
What conditions will increase the diffusion of neurotransmitters?
Signup and view all the answers
Which best represents synaptic transmission?
Signup and view all the answers
The small space between the sending neuron and the receiving neuron is the?
Signup and view all the answers
A molecule that carries information across a synaptic cleft is a?
Signup and view all the answers
What happens when calcium ions enter the synaptic terminal?
Signup and view all the answers
What occurs when neurotransmitter molecules bind to receptors in the receiving neuron?
Signup and view all the answers
If a signal from a sending neuron makes the receiving neuron more negative inside, what occurs?
Signup and view all the answers
Which is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle?
Signup and view all the answers
Which of the following is not a chemical class of neurotransmitters?
Signup and view all the answers
Which neurotransmitter inhibits pain and is mimicked by morphine?
Signup and view all the answers
Which neuron circuit pattern is involved in the control of rhythmic activities such as breathing?
Signup and view all the answers
Nerve cell adhesion molecules (N-CAMs) ________.
Signup and view all the answers
Study Notes
Neuron Classification and Function
- Neurons are functionally classified based on the direction of the nerve impulse relative to the central nervous system.
- Neurotransmitter release and receptor binding influence neuronal activity, affecting whether an action potential is generated.
Action Potentials and Ion Movement
- During depolarization, sodium ions (Na+) move into the cell driven by both electrical and chemical gradients.
- Resting neuron membranes are highly permeable to potassium ions (K+) but only slightly to sodium ions (Na+).
- The Na+-K+ pump actively transports Na+ out of the cell and K+ into the cell to offset ion leakage.
- The absolute refractory period refers to the time after an initial stimulus during which the neuron cannot respond to another stimulus.
Molecular Mechanisms in Neural Activity
- Local anesthetics block voltage-gated Na+ channels, inhibiting action potential generation despite activation of mechanically gated ion channels.
- Exocytosis involves membrane organelles fusing with the membrane, releasing contents out of the cell.
Synaptic Transmission
- The synaptic cleft is the small gap between the sending and receiving neurons where neurotransmission occurs.
- Calcium ions entering the synaptic terminal trigger vesicles containing neurotransmitters to fuse with the sending neuron's plasma membrane.
Neurotransmitters and Their Effects
- Acetylcholine acts as an excitatory neurotransmitter for skeletal muscle.
- Endorphins are neurotransmitters that inhibit pain, mimicking the effects of substances like morphine and heroin.
- Intensity of neuronal signaling can be influenced by the quantity of neurotransmitter released at synapses.
Neuronal Structure and Support
- Neurofibrils are important bundles of neurofilaments that help maintain the shape and integrity of neurons.
- Microglia are glial cells that support neurons' health and can act as macrophages during injury.
Neuronal Circuit Patterns
- Reverberating circuits are associated with controlling rhythmic activities, such as breathing.
Neural Development
- Nerve cell adhesion molecules (N-CAMs) play a critical role in developing neural connections.
Ion Concentrations
- Sodium (Na+) and chloride (Cl-) ions have the highest concentrations outside the cell, influencing membrane potential and action potential generation.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Review key concepts in neural anatomy with these flashcards. This quiz covers the classification of neurons, depolarization processes, and membrane permeability. Ideal for students preparing for their anatomy exams.