Podcast
Questions and Answers
What is the primary function of the nervous system?
What is the primary function of the nervous system?
- To communicate with body cells through electrical impulses (correct)
- To regulate body temperature through blood circulation
- To produce hormones for bodily functions
- To filter toxins from the bloodstream
What are the three overlapping functions of the nervous system?
What are the three overlapping functions of the nervous system?
- Sensory input, integration, motor output (correct)
- Reflex, response, voluntary action
- Sensory input, hormone regulation, motor output
- Stimulus, response, feedback
Which structures are primarily included in the structural classification of the nervous system?
Which structures are primarily included in the structural classification of the nervous system?
- Central nervous system and peripheral nervous system (correct)
- Sensory receptors and muscle fibers
- Hormonal glands and brain lobes
- Spinal cord and cranial nerves
Which part of the nervous system is responsible for regulating involuntary actions?
Which part of the nervous system is responsible for regulating involuntary actions?
Which two parts make up the autonomic nervous system?
Which two parts make up the autonomic nervous system?
What is the primary role of sensory receptors in the nervous system?
What is the primary role of sensory receptors in the nervous system?
Which of the following best describes the functional classification of the nervous system?
Which of the following best describes the functional classification of the nervous system?
What is the primary function of the cell body of a neuron?
What is the primary function of the cell body of a neuron?
What is the primary type of cells that make up nervous tissue?
What is the primary type of cells that make up nervous tissue?
In the classification of neurons, which type carries impulses toward the CNS?
In the classification of neurons, which type carries impulses toward the CNS?
Which of the following best describes white matter in the CNS?
Which of the following best describes white matter in the CNS?
What role do interferons play in the treatment of multiple sclerosis?
What role do interferons play in the treatment of multiple sclerosis?
Why are neuron cell bodies found in the CNS rather than in the PNS?
Why are neuron cell bodies found in the CNS rather than in the PNS?
What type of neurons are classified based on the number of processes extending from the cell body?
What type of neurons are classified based on the number of processes extending from the cell body?
What is the significance of irritability and conductivity in neurons?
What is the significance of irritability and conductivity in neurons?
What is the role of Schwann cells in the peripheral nervous system?
What is the role of Schwann cells in the peripheral nervous system?
Which classification describes small collections of cell bodies outside the CNS?
Which classification describes small collections of cell bodies outside the CNS?
What structures are formed at regular intervals along myelinated fibers?
What structures are formed at regular intervals along myelinated fibers?
How do oligodendrocytes differ from Schwann cells in terms of myelination?
How do oligodendrocytes differ from Schwann cells in terms of myelination?
What is the role of the neurilemma in the peripheral nervous system?
What is the role of the neurilemma in the peripheral nervous system?
What condition is characterized by the gradual destruction of myelin sheaths in the CNS?
What condition is characterized by the gradual destruction of myelin sheaths in the CNS?
Which component is primarily found in the myelin sheath formed by Schwann cells?
Which component is primarily found in the myelin sheath formed by Schwann cells?
What happens to nerve signals when myelin sheaths are compromised?
What happens to nerve signals when myelin sheaths are compromised?
Which function is NOT performed by satellite cells in the peripheral nervous system?
Which function is NOT performed by satellite cells in the peripheral nervous system?
What is the process called that restores the electrical conditions at the membrane to the polarized state?
What is the process called that restores the electrical conditions at the membrane to the polarized state?
Which pump is responsible for restoring the initial concentrations of sodium and potassium ions after repolarization?
Which pump is responsible for restoring the initial concentrations of sodium and potassium ions after repolarization?
What type of conduction occurs when the nerve impulse jumps from node to node along the axon?
What type of conduction occurs when the nerve impulse jumps from node to node along the axon?
What type of reflex involves a two-neuron reflex arc?
What type of reflex involves a two-neuron reflex arc?
Which of the following components is NOT part of a three-neuron reflex arc?
Which of the following components is NOT part of a three-neuron reflex arc?
What makes reflexes predictable and rapid?
What makes reflexes predictable and rapid?
Which part of the nervous system is primarily involved in reflex arcs?
Which part of the nervous system is primarily involved in reflex arcs?
How does myelination affect nerve impulse propagation?
How does myelination affect nerve impulse propagation?
What is the primary ion that is more concentrated inside a resting neuron?
What is the primary ion that is more concentrated inside a resting neuron?
What happens to the polarity of a neuron's membrane during depolarization?
What happens to the polarity of a neuron's membrane during depolarization?
Which stimulus primarily causes neurons to depolarize and generate an impulse?
Which stimulus primarily causes neurons to depolarize and generate an impulse?
What type of potential results from the local depolarization of a neuron's membrane?
What type of potential results from the local depolarization of a neuron's membrane?
What occurs almost immediately after sodium ions rush into the neuron during action potential generation?
What occurs almost immediately after sodium ions rush into the neuron during action potential generation?
What is unique about the nerve impulse regarding its propagation along the axon?
What is unique about the nerve impulse regarding its propagation along the axon?
What happens to the permeability of the neuron's plasma membrane during the rapid outflow of potassium ions?
What happens to the permeability of the neuron's plasma membrane during the rapid outflow of potassium ions?
During which phase does the neuron's membrane maintain a state where it is polarized?
During which phase does the neuron's membrane maintain a state where it is polarized?
Flashcards are hidden until you start studying
Study Notes
Overview of the Nervous System
- Master control and communication system of the body.
- Influences thoughts, actions, and emotions through electrical impulses.
- Functions rapidly to provide immediate responses, working alongside the endocrine system which uses hormones for slower regulation.
Functions of the Nervous System
- Sensory Input: Monitors internal and external changes (stimuli) using sensory receptors.
- Integration: Processes and interprets sensory input to determine appropriate responses.
- Motor Output: Activates muscles or glands to produce a response.
Classifications of the Nervous System
-
Structural Classification:
- Central Nervous System (CNS): Comprises the brain and spinal cord; processes sensory information, integrating commands based on experiences.
- Peripheral Nervous System (PNS): Connects CNS to limbs and organs.
-
Functional Classification:
- Somatic Nervous System: Controls voluntary movements.
- Autonomic Nervous System (ANS): Regulates involuntary bodily functions (smooth muscle, cardiac muscle, and glands); consists of sympathetic (stimulating) and parasympathetic (inhibitory) divisions.
Nervous Tissue Structure
-
Composed of two main cell types: supporting cells and neurons.
-
Supporting Cells:
- Schwann Cells: Form myelin sheaths in the PNS.
- Satellite Cells: Provide protection and cushioning to neuron cell bodies.
-
Neurons: Specialized for transmitting messages; all have a cell body with a nucleus and extending processes (axons and dendrites).
Myelination
- Myelin sheath is essential for electrical insulation around axons.
- Schwann Cells in the PNS wrap around single axons, forming myelin, while Oligodendrocytes in the CNS can surround multiple axons.
- Myelin increases speed of impulse conduction; absence can result in disorders like Multiple Sclerosis (MS) which disrupts nerve signal transmission.
Nervous System Terminology
- CNS: Nuclei (cell body clusters), tracts (nerve fiber bundles).
- PNS: Ganglia (cell body collections), nerves (fiber bundles).
- White Matter: Myelinated regions; Gray Matter: Unmyelinated regions.
Neuron Classification
-
Functional Classification:
- Sensory Neurons: Carry impulses to the CNS.
- Motor Neurons: Carry impulses away from the CNS.
- Association Neurons (Interneurons): Connect sensory and motor neurons.
-
Structural Classification: Based on the number of processes extending from the cell body (unipolar, bipolar, multipolar).
Physiology of Nerve Impulses
- Neurons exhibit irritability (ability to respond to stimuli) and conductivity (ability to transmit impulses).
- Resting neurons are polarized, with differing ion concentrations inside (potassium) and outside (sodium).
- Depolarization occurs when sodium channels open, leading to an influx of sodium ions.
- If strong enough, this triggers an action potential, a full-scale nerve impulse that propagates along the axon.
- Repolarization restores original polarity; the sodium-potassium pump re-establishes ion concentrations.
Saltatory Conduction
- In myelinated fibers, impulses 'jump' from node to node, greatly increasing conduction velocity compared to unmyelinated fibers.
Reflexes and Reflex Arcs
- Reflexes are rapid, involuntary responses to stimuli, typically following a specific, predictable pathway.
- Involve both CNS and PNS, classified as somatic (controlling skeletal muscle) or autonomic (controlling internal organs).
- Reflex arcs consist of five components: receptor, sensory neuron, interneuron, motor neuron, and effector, allowing for quick bodily responses (e.g., knee-jerk reflex).
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
