Action potential
•Download as PPTX, PDF•
6 likes•331 views
An action potential is an electrical signal that propagates along the surface of a neuron membrane due to the movement of sodium and potassium ions through specific ion channels. It occurs in four phases: 1) Resting potential with sodium and potassium channels closed, 2) Depolarization with sodium entry lowering the membrane potential, 3) Repolarization with sodium channel inactivation and potassium efflux restoring the potential, 4) Repolarization continuation with full potential restoration before returning to resting potential. This process allows an electrical signal to travel down an axon through repeated action potentials.
Report
Share
Report
Share
Recommended
Nervous System
The document summarizes the main components and functions of the human nervous system. It describes the central nervous system including the brain and spinal cord. It also describes the peripheral nervous system including cranial nerves and spinal nerves. Finally, it discusses the different types of neurons, their functions, and how they transmit signals in the body.
NERVE PHYSIOLOGY- CLASSIFICATION & PROPERTIES OF NERVE FIBERS
Nerve fibers are classified based on their structure, distribution, origin and function. They can be myelinated or unmyelinated. When injured, the distal portion undergoes Wallerian degeneration over 3 months as the axon and myelin sheath break down. The cell body shows chromatolysis. Regeneration is possible if the nerve ends are close together. New axonal growth occurs rapidly, entering the distal stump at 3-4mm/day. Myelination resumes over a year. Though anatomy recovers, full function returns slowly.
Nerve fibers
Nerve fibers can be classified based on their structure and distribution. There are two main types - myelinated and unmyelinated fibers. Nerve fibers also include somatic and autonomic fibers. Somatic fibers innervate skeletal muscles and the neurotransmitter is acetylcholine, leading to muscle excitation or central inhibition. Autonomic fibers innervate smooth, cardiac muscles and glands to maintain homeostasis, causing excitation or inhibition. Important properties of nerve fibers include excitability, conductivity, unfatigability, refractory periods, all-or-none response, summation, and accommodation.
SYNAPSE
The document discusses the structure and function of chemical synapses. It begins by defining a synapse as the junction between two nerve cells. It then describes the key anatomical components of a chemical synapse, including the presynaptic knob, synaptic cleft, and postsynaptic membrane. It explains the process of neurotransmission, including the release of neurotransmitters into the synaptic cleft, their binding to receptors on the postsynaptic membrane, and the resulting postsynaptic potentials. The document also discusses inhibition at synapses, the properties of synaptic transmission, and examples of neurotransmitters.
Neuron Structure
This document describes the structure and function of neurons and synapses. It discusses the key parts of neurons including the soma, dendrites, axon, and myelin sheath. It classifies neurons as multipolar, bipolar, or pseudounipolar. Synapses are described as the junction between an axon and dendrite or cell body. The stages of synaptic transmission and types of mediators are outlined. The principles of spatial and temporal summation are introduced as ways neurons integrate multiple inputs. Reflexes are defined as automatic sensory-motor responses mediated by the central nervous system. Inhibition is described as a process that suppresses excitation.
Cns 14
The reticular formation is a network of neurons located in the brainstem that serves several important functions:
1. It helps regulate arousal and consciousness through the reticular activating system. This system projects to the thalamus and maintains an alert cerebral cortex. Damage can result in coma.
2. It modulates muscle tone through facilitatory and inhibitory projections to the spinal cord. The pontine reticular formation facilitates antigravity muscles while the medullary region inhibits them.
3. In addition to arousal and motor control, the reticular formation is involved in other autonomic functions like respiration, cardiovascular regulation, vomiting, coughing, and processing pain signals.
Neurophysiology
The document provides an overview of neurophysiology, the study of the functioning of the nervous system. It describes the basic structure and components of neurons, including the cell body, dendrites, axon, synapse, and myelin sheath. It discusses the types of neurons, including sensory and motor neurons, and how they differ in structure and function. The document also explains how neurons transmit signals through electrical and chemical processes, including the generation and propagation of action potentials along axons and the transmission of signals across synapses using neurotransmitters.
Peripheral and Autonomic Nervous System EHS Unit 4
This document discusses the peripheral and autonomic nervous systems. It describes the major structures of the peripheral nervous system, including the 12 cranial nerves and 31 spinal nerve pairs, and their functions. It differentiates between afferent and efferent neurons. It also describes how the autonomic nervous system regulates body functions through the sympathetic and parasympathetic nervous systems in a manner that is outside of voluntary control.
Recommended
Nervous System
The document summarizes the main components and functions of the human nervous system. It describes the central nervous system including the brain and spinal cord. It also describes the peripheral nervous system including cranial nerves and spinal nerves. Finally, it discusses the different types of neurons, their functions, and how they transmit signals in the body.
NERVE PHYSIOLOGY- CLASSIFICATION & PROPERTIES OF NERVE FIBERS
Nerve fibers are classified based on their structure, distribution, origin and function. They can be myelinated or unmyelinated. When injured, the distal portion undergoes Wallerian degeneration over 3 months as the axon and myelin sheath break down. The cell body shows chromatolysis. Regeneration is possible if the nerve ends are close together. New axonal growth occurs rapidly, entering the distal stump at 3-4mm/day. Myelination resumes over a year. Though anatomy recovers, full function returns slowly.
Nerve fibers
Nerve fibers can be classified based on their structure and distribution. There are two main types - myelinated and unmyelinated fibers. Nerve fibers also include somatic and autonomic fibers. Somatic fibers innervate skeletal muscles and the neurotransmitter is acetylcholine, leading to muscle excitation or central inhibition. Autonomic fibers innervate smooth, cardiac muscles and glands to maintain homeostasis, causing excitation or inhibition. Important properties of nerve fibers include excitability, conductivity, unfatigability, refractory periods, all-or-none response, summation, and accommodation.
SYNAPSE
The document discusses the structure and function of chemical synapses. It begins by defining a synapse as the junction between two nerve cells. It then describes the key anatomical components of a chemical synapse, including the presynaptic knob, synaptic cleft, and postsynaptic membrane. It explains the process of neurotransmission, including the release of neurotransmitters into the synaptic cleft, their binding to receptors on the postsynaptic membrane, and the resulting postsynaptic potentials. The document also discusses inhibition at synapses, the properties of synaptic transmission, and examples of neurotransmitters.
Neuron Structure
This document describes the structure and function of neurons and synapses. It discusses the key parts of neurons including the soma, dendrites, axon, and myelin sheath. It classifies neurons as multipolar, bipolar, or pseudounipolar. Synapses are described as the junction between an axon and dendrite or cell body. The stages of synaptic transmission and types of mediators are outlined. The principles of spatial and temporal summation are introduced as ways neurons integrate multiple inputs. Reflexes are defined as automatic sensory-motor responses mediated by the central nervous system. Inhibition is described as a process that suppresses excitation.
Cns 14
The reticular formation is a network of neurons located in the brainstem that serves several important functions:
1. It helps regulate arousal and consciousness through the reticular activating system. This system projects to the thalamus and maintains an alert cerebral cortex. Damage can result in coma.
2. It modulates muscle tone through facilitatory and inhibitory projections to the spinal cord. The pontine reticular formation facilitates antigravity muscles while the medullary region inhibits them.
3. In addition to arousal and motor control, the reticular formation is involved in other autonomic functions like respiration, cardiovascular regulation, vomiting, coughing, and processing pain signals.
Neurophysiology
The document provides an overview of neurophysiology, the study of the functioning of the nervous system. It describes the basic structure and components of neurons, including the cell body, dendrites, axon, synapse, and myelin sheath. It discusses the types of neurons, including sensory and motor neurons, and how they differ in structure and function. The document also explains how neurons transmit signals through electrical and chemical processes, including the generation and propagation of action potentials along axons and the transmission of signals across synapses using neurotransmitters.
Peripheral and Autonomic Nervous System EHS Unit 4
This document discusses the peripheral and autonomic nervous systems. It describes the major structures of the peripheral nervous system, including the 12 cranial nerves and 31 spinal nerve pairs, and their functions. It differentiates between afferent and efferent neurons. It also describes how the autonomic nervous system regulates body functions through the sympathetic and parasympathetic nervous systems in a manner that is outside of voluntary control.
Sensory Physiology
The document summarizes sensory physiology, including the structure and function of sensory receptors and neural pathways. It discusses how different sensory receptors transduce various stimuli like touch, temperature, sound, and light into nerve impulses. The receptors are categorized based on their modality and location. The pathways from receptors to the central nervous system are described for each sensory system. Adaptation and processing of sensory information in the brain is also overviewed.
Presentation NEUROMUSCULAR JUNCTION
The neuromuscular junction is the chemical synapse between a motor neuron and muscle fiber. When an action potential reaches the motor neuron terminal, calcium ions enter and cause vesicles to release acetylcholine into the synaptic cleft. Acetylcholine then binds to nicotinic receptors on the muscle fiber, opening sodium channels and causing an endplate potential that generates an action potential in the muscle fiber, leading to muscle contraction. Acetylcholinesterase breaks down acetylcholine to terminate the signal and allow muscle relaxation.
Sensory system receptors.hussein f.sakr
The document discusses the central nervous system and sensory system. It describes the main components of the sensory unit including sensory axons, peripheral branches, and receptors. The main types of sensory receptors are described based on the stimuli they detect such as mechanoreceptors, chemoreceptors, photoreceptors, and thermoreceptors. The properties of sensory receptors including specificity, excitability through receptor potentials, adaptation, rate of discharge, and neural coding of sensory information are explained.
Neuron
This document provides an overview of neuron structure and nerve impulse propagation. It discusses the key components of a neuron including the cell body, dendrites and axon. It describes ion channels and their role in establishing the resting membrane potential. The document explains how an action potential is generated through a positive feedback loop initiated at the threshold. It discusses the absolute and relative refractory periods and how conduction velocity depends on the diameter and myelination of the axon. In summary, the document outlines the basics of neuron anatomy and function, focusing on membrane potentials, ion channels, action potential generation and propagation.
Nervous System Presentation
The nervous system is divided into the central nervous system (CNS) and peripheral nervous system (PNS). The CNS includes the brain and spinal cord. The PNS includes nerves connecting the CNS to other parts of the body. The PNS is further divided into the somatic and autonomic nervous systems. The autonomic nervous system regulates involuntary body functions and is divided into the sympathetic and parasympathetic nervous systems. The brain contains several parts that each have specific functions like processing sensory information, motor control, and regulating homeostasis. Neurons transmit signals as electrical impulses through a process involving ion exchanges across the cell membrane.
Receptor
This document discusses receptors and neurons that detect sensory information. It begins by defining perception and describing how sensory information is transmitted from receptors to the central nervous system. It then categorizes the different sensory modalities like touch, pain, temperature, and proprioception. The document goes on to describe the different types of sensory receptors, including their locations, the stimuli they detect, and whether they adapt rapidly or slowly. It provides examples of specific receptors like Meissner corpuscles, Pacinian corpuscles, and thermoreceptors. In closing, it notes the uneven distribution of receptors in the skin and modalities detected in the skin.
Action potential
1. An action potential occurs when there is a rapid change in the membrane potential of a neuron from a negative resting potential to a positive potential and then back to a negative potential. This is driven by the movement of ions across the cell membrane through voltage-gated ion channels.
2. For an action potential to be initiated, the membrane potential must be depolarized beyond the threshold potential of around -65mV. This opens voltage-gated sodium channels, allowing sodium ions to enter the cell.
3. The influx of sodium ions causes further depolarization, followed by the opening of voltage-gated potassium channels which causes repolarization back to the resting potential and then hyperpolarization below the resting potential.
Peripheral Nervous System
The document discusses the peripheral nervous system. It begins by defining the nervous system and its main components - the central nervous system and peripheral nervous system. The peripheral nervous system has two main divisions: somatic and autonomic. The somatic division includes sensory and motor neurons that control voluntary movement. The autonomic nervous system controls involuntary functions and has sympathetic and parasympathetic divisions. The document goes on to describe various nerves, neurons, and structures that make up the peripheral nervous system.
6. cns 2
Graded potentials are local changes in membrane potential that vary in strength depending on the stimulus. They spread through passive diffusion but decay over short distances. Action potentials occur when the membrane reaches threshold potential, causing voltage-gated sodium and potassium channels to open and reverse the membrane potential before restoring it. They travel along axons through contiguous conduction. At synapses, neurotransmitters released from presynaptic neurons can excite or inhibit postsynaptic neurons through temporal and spatial summation of EPSPs and IPSPs. Presynaptic inputs determine postsynaptic responses through facilitation or inhibition of neurotransmitter release.
Smell and taste by Pandian M. Dept of Physiology, DYPMCKOP,MH
Describe the basic features of the neural elements in the olfactory epithelium and olfactory bulb.
Describe signal transduction in odorant receptors.
Outline the pathway by which impulses generated in the olfactory epithelium reach the olfactory cortex.
Describe the location and cellular composition of taste buds.
Name the five major taste receptors and signal transduction mechanisms in these receptors.
Outline the pathways by which impulses generated in taste receptors reach the insular cortex.
Physiology of the Nervous System
The brain and the spinal cord are the central nervous system, and they represent the main organs of the nervous system.
Nervous system
The document discusses the nervous system and its components. It describes the nervous system as having two main divisions - the central nervous system (CNS) and the peripheral nervous system. The CNS contains the brain and spinal cord while the peripheral nervous system contains nerves that connect the CNS to the rest of the body. The document also describes the basic types of cells that make up the nervous system - neurons, which transmit nerve impulses, and neuroglia or glial cells, which support neurons. It provides details on the structure and function of neurons and how nerve impulses are conducted.
Lect 3. (general principle of git motility)
The gastrointestinal smooth muscle functions as a syncytium, with individual fibers electrically connected through gap junctions. Electrical activity in the form of slow waves and spike potentials causes rhythmic contractions. Slow waves do not cause contraction directly but allow spike potentials to occur. Spike potentials cause entry of calcium ions, which bind to calmodulin and activate myosin to generate contraction. Tonic contraction is continuous and can be caused by repetitive spike potentials or other factors maintaining partial membrane depolarization.
Nervous system
The nervous system is the chief controlling and coordinating system of the body. It consists of the brain, spinal cord, sensory organs, and nerves. The nervous system controls and regulates all voluntary and involuntary activities. It has three main functions: sensory function to collect information, integration to process sensory input and make decisions, and motor function to send responses to muscles and glands. The central nervous system includes the brain and spinal cord, which interpret sensory information. The peripheral nervous system includes nerves outside the brain and spinal cord that connect to sensory receptors.
Autonomic nervous system Physiology
The autonomic nervous system (ANS) controls involuntary functions like heartbeat, breathing, and digestion. It has two divisions - the sympathetic and parasympathetic systems.
The sympathetic system prepares the body for "fight or flight" through actions like increasing heart rate. It uses norepinephrine as a neurotransmitter. The parasympathetic system allows the body to "rest and digest" through actions like slowing the heart rate. It uses acetylcholine as a neurotransmitter.
Both systems involve two neurons - a preganglionic neuron from the CNS and a postganglionic neuron. They differ in the lengths of their neurons and the locations of their cell bodies. Together they work to maintain homeostasis through complementary
Extra pyramidal tracts.pptx
The document discusses several extrapyramidal tracts in the brain and spinal cord that are involved in motor control. It describes the reticular formation and reticulospinal tracts originating in the pons and medulla. It also discusses the tectospinal tract originating in the superior colliculus, rubrospinal tract originating in the red nucleus, and vestibulospinal tract originating in the vestibular nuclei. Clinical signs of upper motor neuron lesions that damage these extrapyramidal tracts include spasticity, hypertonia, and exaggerated reflexes. Lower motor neuron lesions cause flaccid paralysis, atrophy, and loss of reflexes.
Functions of neurotransmitters and neuropeptides
There are over 100 known neurotransmitters that can be divided into small-molecule neurotransmitters and neuropeptides. Small-molecule neurotransmitters like acetylcholine, glutamate, GABA, and biogenic amines like norepinephrine, dopamine, and serotonin act quickly by opening or closing ion channels, while neuropeptides like substance P, enkephalins, and endorphins act more slowly through second messenger systems to influence cell chemistry. Neurotransmitters can have excitatory or inhibitory effects on postsynaptic neurons and help regulate processes in the brain and body.
Nervous system
The document discusses the structure and function of the nervous system. It notes that neurons, along with supporting glial cells, make up the central and peripheral nervous systems. Information is transmitted between neurons electrochemically through cell bodies, axons, and synapses using neurotransmitters. The central nervous system consists of the brain and spinal cord, which contain grey matter on the inside and white matter on the outside. The peripheral nervous system connects receptors, the CNS, and effectors through nerves. Sensory nerves transmit information from receptors to the CNS while motor nerves transmit information from the CNS to effectors.
Physiology of autonomic nervous system
The document discusses the autonomic nervous system (ANS), which is divided into the sympathetic and parasympathetic nervous systems. The sympathetic system activates the "fight or flight" response and increases heart rate and metabolism. The parasympathetic system activates the "rest and digest" response and decreases heart rate and increases digestion. The ANS innervates smooth muscle, cardiac muscle and glands, and is involved in functions like sweating, digestion, and sexual arousal.
Nervous system
The nervous system is made up of nerves and cells that carry messages between the brain, spinal cord, and body. It is divided into the central nervous system (brain and spinal cord) and peripheral nervous system. The central nervous system controls functions like blood pressure, breathing, hormone levels, and behaviors. It is composed of neurons, neuroglia, and other supporting cells. Neurons communicate via electrical and chemical signals to control bodily functions and respond to internal and external stimuli.
RestingMembranePotential
The resting membrane potential of cells is normally more negative inside the cell compared to outside, ranging from -9mV to -100mV. This polarization is due to the concentration gradients of sodium ions outside the cell and potassium ions inside the cell. When a stimulus causes voltage-gated sodium channels to open, sodium ions rush into the cell, depolarizing the membrane and initiating an action potential. Then, voltage-gated potassium channels open, allowing potassium ions to efflux and repolarize the membrane. Sodium-potassium pumps then restore the membrane back to its resting potential.
BSC Lecture Action potential.pdf
1) All cells possess electrical excitability, the ability to generate an action potential in response to a stimulus.
2) An action potential is an electrical signal that propagates along the neuronal membrane due to the movement of sodium and potassium ions through ion channels.
3) The resting membrane potential is maintained by the uneven distribution of ions across the membrane and the sodium-potassium pump, which works to keep the intracellular concentration of sodium ions low and potassium ions high.
More Related Content
What's hot
Sensory Physiology
The document summarizes sensory physiology, including the structure and function of sensory receptors and neural pathways. It discusses how different sensory receptors transduce various stimuli like touch, temperature, sound, and light into nerve impulses. The receptors are categorized based on their modality and location. The pathways from receptors to the central nervous system are described for each sensory system. Adaptation and processing of sensory information in the brain is also overviewed.
Presentation NEUROMUSCULAR JUNCTION
The neuromuscular junction is the chemical synapse between a motor neuron and muscle fiber. When an action potential reaches the motor neuron terminal, calcium ions enter and cause vesicles to release acetylcholine into the synaptic cleft. Acetylcholine then binds to nicotinic receptors on the muscle fiber, opening sodium channels and causing an endplate potential that generates an action potential in the muscle fiber, leading to muscle contraction. Acetylcholinesterase breaks down acetylcholine to terminate the signal and allow muscle relaxation.
Sensory system receptors.hussein f.sakr
The document discusses the central nervous system and sensory system. It describes the main components of the sensory unit including sensory axons, peripheral branches, and receptors. The main types of sensory receptors are described based on the stimuli they detect such as mechanoreceptors, chemoreceptors, photoreceptors, and thermoreceptors. The properties of sensory receptors including specificity, excitability through receptor potentials, adaptation, rate of discharge, and neural coding of sensory information are explained.
Neuron
This document provides an overview of neuron structure and nerve impulse propagation. It discusses the key components of a neuron including the cell body, dendrites and axon. It describes ion channels and their role in establishing the resting membrane potential. The document explains how an action potential is generated through a positive feedback loop initiated at the threshold. It discusses the absolute and relative refractory periods and how conduction velocity depends on the diameter and myelination of the axon. In summary, the document outlines the basics of neuron anatomy and function, focusing on membrane potentials, ion channels, action potential generation and propagation.
Nervous System Presentation
The nervous system is divided into the central nervous system (CNS) and peripheral nervous system (PNS). The CNS includes the brain and spinal cord. The PNS includes nerves connecting the CNS to other parts of the body. The PNS is further divided into the somatic and autonomic nervous systems. The autonomic nervous system regulates involuntary body functions and is divided into the sympathetic and parasympathetic nervous systems. The brain contains several parts that each have specific functions like processing sensory information, motor control, and regulating homeostasis. Neurons transmit signals as electrical impulses through a process involving ion exchanges across the cell membrane.
Receptor
This document discusses receptors and neurons that detect sensory information. It begins by defining perception and describing how sensory information is transmitted from receptors to the central nervous system. It then categorizes the different sensory modalities like touch, pain, temperature, and proprioception. The document goes on to describe the different types of sensory receptors, including their locations, the stimuli they detect, and whether they adapt rapidly or slowly. It provides examples of specific receptors like Meissner corpuscles, Pacinian corpuscles, and thermoreceptors. In closing, it notes the uneven distribution of receptors in the skin and modalities detected in the skin.
Action potential
1. An action potential occurs when there is a rapid change in the membrane potential of a neuron from a negative resting potential to a positive potential and then back to a negative potential. This is driven by the movement of ions across the cell membrane through voltage-gated ion channels.
2. For an action potential to be initiated, the membrane potential must be depolarized beyond the threshold potential of around -65mV. This opens voltage-gated sodium channels, allowing sodium ions to enter the cell.
3. The influx of sodium ions causes further depolarization, followed by the opening of voltage-gated potassium channels which causes repolarization back to the resting potential and then hyperpolarization below the resting potential.
Peripheral Nervous System
The document discusses the peripheral nervous system. It begins by defining the nervous system and its main components - the central nervous system and peripheral nervous system. The peripheral nervous system has two main divisions: somatic and autonomic. The somatic division includes sensory and motor neurons that control voluntary movement. The autonomic nervous system controls involuntary functions and has sympathetic and parasympathetic divisions. The document goes on to describe various nerves, neurons, and structures that make up the peripheral nervous system.
6. cns 2
Graded potentials are local changes in membrane potential that vary in strength depending on the stimulus. They spread through passive diffusion but decay over short distances. Action potentials occur when the membrane reaches threshold potential, causing voltage-gated sodium and potassium channels to open and reverse the membrane potential before restoring it. They travel along axons through contiguous conduction. At synapses, neurotransmitters released from presynaptic neurons can excite or inhibit postsynaptic neurons through temporal and spatial summation of EPSPs and IPSPs. Presynaptic inputs determine postsynaptic responses through facilitation or inhibition of neurotransmitter release.
Smell and taste by Pandian M. Dept of Physiology, DYPMCKOP,MH
Describe the basic features of the neural elements in the olfactory epithelium and olfactory bulb.
Describe signal transduction in odorant receptors.
Outline the pathway by which impulses generated in the olfactory epithelium reach the olfactory cortex.
Describe the location and cellular composition of taste buds.
Name the five major taste receptors and signal transduction mechanisms in these receptors.
Outline the pathways by which impulses generated in taste receptors reach the insular cortex.
Physiology of the Nervous System
The brain and the spinal cord are the central nervous system, and they represent the main organs of the nervous system.
Nervous system
The document discusses the nervous system and its components. It describes the nervous system as having two main divisions - the central nervous system (CNS) and the peripheral nervous system. The CNS contains the brain and spinal cord while the peripheral nervous system contains nerves that connect the CNS to the rest of the body. The document also describes the basic types of cells that make up the nervous system - neurons, which transmit nerve impulses, and neuroglia or glial cells, which support neurons. It provides details on the structure and function of neurons and how nerve impulses are conducted.
Lect 3. (general principle of git motility)
The gastrointestinal smooth muscle functions as a syncytium, with individual fibers electrically connected through gap junctions. Electrical activity in the form of slow waves and spike potentials causes rhythmic contractions. Slow waves do not cause contraction directly but allow spike potentials to occur. Spike potentials cause entry of calcium ions, which bind to calmodulin and activate myosin to generate contraction. Tonic contraction is continuous and can be caused by repetitive spike potentials or other factors maintaining partial membrane depolarization.
Nervous system
The nervous system is the chief controlling and coordinating system of the body. It consists of the brain, spinal cord, sensory organs, and nerves. The nervous system controls and regulates all voluntary and involuntary activities. It has three main functions: sensory function to collect information, integration to process sensory input and make decisions, and motor function to send responses to muscles and glands. The central nervous system includes the brain and spinal cord, which interpret sensory information. The peripheral nervous system includes nerves outside the brain and spinal cord that connect to sensory receptors.
Autonomic nervous system Physiology
The autonomic nervous system (ANS) controls involuntary functions like heartbeat, breathing, and digestion. It has two divisions - the sympathetic and parasympathetic systems.
The sympathetic system prepares the body for "fight or flight" through actions like increasing heart rate. It uses norepinephrine as a neurotransmitter. The parasympathetic system allows the body to "rest and digest" through actions like slowing the heart rate. It uses acetylcholine as a neurotransmitter.
Both systems involve two neurons - a preganglionic neuron from the CNS and a postganglionic neuron. They differ in the lengths of their neurons and the locations of their cell bodies. Together they work to maintain homeostasis through complementary
Extra pyramidal tracts.pptx
The document discusses several extrapyramidal tracts in the brain and spinal cord that are involved in motor control. It describes the reticular formation and reticulospinal tracts originating in the pons and medulla. It also discusses the tectospinal tract originating in the superior colliculus, rubrospinal tract originating in the red nucleus, and vestibulospinal tract originating in the vestibular nuclei. Clinical signs of upper motor neuron lesions that damage these extrapyramidal tracts include spasticity, hypertonia, and exaggerated reflexes. Lower motor neuron lesions cause flaccid paralysis, atrophy, and loss of reflexes.
Functions of neurotransmitters and neuropeptides
There are over 100 known neurotransmitters that can be divided into small-molecule neurotransmitters and neuropeptides. Small-molecule neurotransmitters like acetylcholine, glutamate, GABA, and biogenic amines like norepinephrine, dopamine, and serotonin act quickly by opening or closing ion channels, while neuropeptides like substance P, enkephalins, and endorphins act more slowly through second messenger systems to influence cell chemistry. Neurotransmitters can have excitatory or inhibitory effects on postsynaptic neurons and help regulate processes in the brain and body.
Nervous system
The document discusses the structure and function of the nervous system. It notes that neurons, along with supporting glial cells, make up the central and peripheral nervous systems. Information is transmitted between neurons electrochemically through cell bodies, axons, and synapses using neurotransmitters. The central nervous system consists of the brain and spinal cord, which contain grey matter on the inside and white matter on the outside. The peripheral nervous system connects receptors, the CNS, and effectors through nerves. Sensory nerves transmit information from receptors to the CNS while motor nerves transmit information from the CNS to effectors.
Physiology of autonomic nervous system
The document discusses the autonomic nervous system (ANS), which is divided into the sympathetic and parasympathetic nervous systems. The sympathetic system activates the "fight or flight" response and increases heart rate and metabolism. The parasympathetic system activates the "rest and digest" response and decreases heart rate and increases digestion. The ANS innervates smooth muscle, cardiac muscle and glands, and is involved in functions like sweating, digestion, and sexual arousal.
Nervous system
The nervous system is made up of nerves and cells that carry messages between the brain, spinal cord, and body. It is divided into the central nervous system (brain and spinal cord) and peripheral nervous system. The central nervous system controls functions like blood pressure, breathing, hormone levels, and behaviors. It is composed of neurons, neuroglia, and other supporting cells. Neurons communicate via electrical and chemical signals to control bodily functions and respond to internal and external stimuli.
What's hot (20)
Smell and taste by Pandian M. Dept of Physiology, DYPMCKOP,MH
Smell and taste by Pandian M. Dept of Physiology, DYPMCKOP,MH
Similar to Action potential
RestingMembranePotential
The resting membrane potential of cells is normally more negative inside the cell compared to outside, ranging from -9mV to -100mV. This polarization is due to the concentration gradients of sodium ions outside the cell and potassium ions inside the cell. When a stimulus causes voltage-gated sodium channels to open, sodium ions rush into the cell, depolarizing the membrane and initiating an action potential. Then, voltage-gated potassium channels open, allowing potassium ions to efflux and repolarize the membrane. Sodium-potassium pumps then restore the membrane back to its resting potential.
BSC Lecture Action potential.pdf
1) All cells possess electrical excitability, the ability to generate an action potential in response to a stimulus.
2) An action potential is an electrical signal that propagates along the neuronal membrane due to the movement of sodium and potassium ions through ion channels.
3) The resting membrane potential is maintained by the uneven distribution of ions across the membrane and the sodium-potassium pump, which works to keep the intracellular concentration of sodium ions low and potassium ions high.
Neural Transmission
The document discusses neural transmission and the action potential in neurons. It explains that:
- An action potential is generated when the membrane is depolarized by the influx of sodium ions through voltage-gated sodium channels.
- This creates an all-or-none electrical signal that propagates down the neuron via voltage-sensitive ion channels.
- The neuron maintains a resting potential through ion concentration gradients and ion pumps/channels, allowing it to initiate an action potential when sufficiently stimulated.
BSC Lecture Action potential.pptx
1) Action potentials are electrical signals that propagate along excitable cell membranes and are initiated by stimuli. They involve the movement of ions through voltage-gated ion channels.
2) In neurons, an action potential is a brief reversal of the membrane potential followed by repolarization. This allows communication over long distances.
3) Cardiac action potentials have a depolarizing phase, plateau phase, and repolarizing phase due to calcium ion involvement. This allows for sustained contraction of heart muscle.
Why do ion channels not function like open poresWhat is membrane .pdf
Why do ion channels not function like open pores?
What is membrane potential?
How do K+ leak channels work? Why is the membrane potential of a resting cell negative?
What is patch clamp recording? What is one of the major insights gained from patch clamp
reporting experiments?
Compare and contrast the three types of gated ion channels.
Be familiar with the different parts of a neuron.
During an action potential, what happens to the membrane potential, voltage-gated Na+
channels, Na+ ions, voltage gated K+ channels, K+ ions, and Na+-K+ ion pumps?
When an action potential reaches a synapse, what happens to the Ca2+ channels, Ca2+ ions,
neurotransmitters, transmitter-gated ion channels, and the post synaptic neuron?
What effect do excitatory or inhibitory neurotransmitters have on postsynaptic cells?
What is an example of a mechanically gated ion channel?
Solution
1.Excitable cells, such as fast-acting neurons and muscle cells, have specialized channels that
open in response to a signal and permit rapid ion movement across the cell membrane. The
opening of just a single ion channel alters the electrical charge on both sides of the membrane.
The resulting charge differential then causes adjacent voltage-sensitive channels to open in
chain-reaction fashion, creating a self-propagating electrical signal that travels down the entire
length of the cell. Sometimes, this sequence of events is triggered when a chemical signal —
such as a neurotransmitter — binds to an ion channel receptor on cell\'s surface. Other times, a
cell\'s ion channels open in response to mechanical (rather than chemical) stimuli.
2.In cells of all types, there is an electrical potential difference between the inside of the cell and
the surrounding extracellular fluid. This is termed the membrane potential of the cell. When a
nerve or muscle cell is at \"rest\", its membrane potential is called the resting membrane
potential. In a typical neuron, this is about –70 millivolts (mV). The minus sign indicates that the
inside of the cell is negative with respect to the surrounding extracellular fluid.
3.The leak channels allow K+ to move across the cell membrane down their gradients (from a
high concentration toward a lower concentration).
With the combined ion pumping and leakage of ions, the cell can maintain a stable resting
membrane potential and create membrane potential of a resting cell negative.
4.Patch clamp recording is an extremely useful technique for investigating the biophysical
properties of the ion channels that control neuronal activation.
The procedure involves pressing a glass micropipette against a cell in order to isolate a small
“patch” of membrane that contains one or more ion channels.
The experimental setup further allows scientists to “clamp” the electrical environment of the
patched area by precisely controlling the voltage across the cell membrane, which, depending on
the ion channels present, impacts the flow of ions through the membrane and allow for int.
Physiology com3-week2
The document discusses membrane potential and action potentials. It begins by defining action potentials as signals that trigger communication between cells through electrical and chemical signaling. It then discusses:
- Excitable cells like neurons, muscle and endocrine cells that are able to generate and conduct action potentials.
- The resting membrane potential of -70mV that exists due to ion concentration gradients established by the sodium-potassium pump and selective permeability of the membrane.
- How action potentials are initiated when the membrane potential rapidly depolarizes past a threshold due to opening of voltage-gated sodium channels, then repolarizes due to opening of voltage-gated potassium channels.
BioT2C3-Action potential-transmission of impulse 2015-student.ppt
The document discusses resting potential and action potential in neurons. It defines resting potential as the membrane potential of a neuron when not conducting an impulse, which is around -70 mV for a resting neuron. It defines action potential as the state of the cell membrane while conducting an impulse, which is triggered when voltage-gated sodium channels open and sodium rushes into the cell, reversing the charge difference and allowing propagation of the impulse along the axon.
Membrane potentials
Nerve cells transmit electrical signals through action potentials. Action potentials are brief changes in the electrical potential across the cell membrane that are triggered when the membrane potential reaches a threshold. They are generated by the rapid influx of sodium ions through voltage-gated sodium channels, which causes further opening of these channels in a positive feedback loop. After peaking, the membrane repolarizes as sodium channels inactivate and potassium channels open, restoring the ion gradients. Action potentials propagate along axons without loss of strength through the active opening of sodium channels just beyond the leading edge of depolarization.
1 Sem Chap-3 Neuromuscular phys..pptx
The nervous system allows animals to detect and communicate information about the external and internal environment. It has two main parts: the central nervous system (CNS) and peripheral nervous system (PNS).
Neurons are the basic functional units and carry electrical signals through their cell body, dendrites, and axon. The axon is covered by a myelin sheath that insulates and speeds up signal transmission. At nodes of Ranvier, gaps in the myelin allow signals to travel faster.
The resting membrane potential of neurons is around -70mV, created by ion concentration gradients and selective permeability to ions like potassium and sodium. When stimulated, neurons generate action potentials through changes in sodium and potassium permeability that
cardiac ion channels and channelopathies
The document discusses ion channels and their role in generating cardiac action potentials. It begins by defining ion channels as pore-forming proteins that gate the flow of ions across cell membranes. It then describes the key properties of ion channels including selectivity, gating, and their role in establishing membrane potentials. The remainder of the document details the specific ion channels involved in each phase of the cardiac action potential, including the fast sodium current underlying the upstroke in Phase 0, the potassium and chloride currents producing Phase 1 repolarization, the calcium and potassium currents maintaining the Phase 2 plateau, and the currents responsible for Phase 3 repolarization. Pacemaker cell action potentials are also discussed, noting their unique pacemaker potential in Phase 4 and lack of Phase
Action potential (niraj)
The document discusses the generation and propagation of action potentials in neurons. It begins by explaining the resting membrane potential, which arises from ion concentration gradients maintained by the sodium-potassium pump and potassium leakage channels. It then describes how an action potential is triggered when the membrane potential reaches a threshold, causing voltage-gated sodium channels to open and sodium ions to rush in, rapidly depolarizing the membrane. This wave of depolarization then propagates along the neuron as adjacent areas are triggered to reach threshold. The action potential involves sequential phases of depolarization, repolarization, and hyperpolarization.
B.Sc.(Micro+Biotech) II Animal & Plant Physiology Unit 4.2 Transmission of ne...
The transmission of nerve impulses occurs via electrical signals along axons. When stimulated, sodium channels open allowing sodium ions to flood into the axon, reversing the normal negative resting potential and causing rapid depolarization. Then, potassium channels open and potassium ions diffuse out, beginning repolarization. The sodium-potassium pump restores the ion gradients and resting potential. This process, known as an action potential, allows signals to propagate rapidly along axons.
P.resting membrane potential by Artist Rimsha
The resting membrane potential of a neuron is determined by concentration gradients of ions like potassium, sodium, and chloride across the neuronal membrane. At rest, the intracellular concentration of potassium is higher than extracellular, while sodium is higher extracellular than intracellular. This creates an electrochemical gradient that drives the passive diffusion of potassium out of and sodium into the cell. However, the membrane is more permeable to potassium than sodium, resulting in a steady resting potential of around -70 mV, with the inside of the cell being negatively charged relative to the outside. Ion channels including passive leak channels and voltage-gated channels regulate ion flow and influence changes in membrane potential during neuronal signaling.
Cell membrane potential
1) Neuron membranes maintain a resting potential through ion gradients established by sodium-potassium pumps.
2) When stimulated, voltage-gated ion channels allow sodium to enter and potassium to leave, depolarizing the membrane and initiating an action potential.
3) Action potentials propagate as waves down axons through local currents, transmitting nerve impulses as electrical signals along the length of neurons.
Memberane potential
Membrane potential (also transmembrane potential or membrane voltage) is the difference in electric potential between the interior and the exterior of a biological cell. ... Almost all plasma membranes have an electrical potential across them, with the inside usually negative with respect to the outside.
Letcture 39 electrical potential i
1. The document discusses the electrical properties of cell membranes, including diffusion potential, equilibrium potential, and the Donnan effect.
2. Diffusion potential is the voltage difference established across a membrane when ions diffuse down their concentration gradient through selective permeable pathways. The Nernst equation is used to calculate equilibrium potential for a single ion based on its intracellular and extracellular concentrations.
3. The Goldman equation calculates membrane potential based on permeability and concentrations of multiple permeable ions.
4. The Donnan effect refers to the uneven distribution of charged particles across a semipermeable membrane containing impermeable ions, maintaining concentration gradients and establishing a membrane potential.
Physiology of NERVE IMPULSE and action potential
1. The nerve impulse is initiated when a stimulus opens sodium ion channels in the neuron's membrane, causing sodium ions to rush in and depolarize the membrane.
2. As the membrane depolarizes past its threshold, an action potential is generated as the membrane potential rapidly rises and falls in a wave that travels down the axon.
3. The action potential involves changes in the permeability of the membrane to sodium and potassium ions, resulting in an upswing in membrane potential during depolarization and a subsequent downswing during repolarization and hyperpolarization as the neuron returns to its resting potential.
Nerve physiology
The document discusses the history and discoveries of nerve physiology. It describes how Joseph Erlanger and Herbert Gasser developed tools to measure nerve impulses using oscilloscopes. Their work led to their shared Nobel Prize in 1944. Later, Hodgkin, Huxley, and Eccles advanced understanding of ionic mechanisms in nerves through experiments on squid nerves. Neher and Sakmann also received a Nobel Prize for developing a technique to measure currents through single ion channels. The document then provides detailed explanations and diagrams about the resting membrane potential, action potentials, graded potentials, and the mechanisms of nerve signal propagation.
Resting membrane potential and action potential
The document discusses the resting membrane potential and action potential in neurons. It explains that:
1) The resting membrane potential is around -70mV, created by different ion concentrations inside and outside the neuron.
2) Graded potentials are local, short-lived changes in membrane potential caused by ion channels opening briefly in response to stimuli.
3) Action potentials are brief, large changes in potential from -70mV to +30mV caused by voltage-gated sodium and potassium channels. The influx of sodium ions depolarizes the membrane before potassium channels repolarize it.
4) Action potentials propagate along the axon as one area repolarizes and depolarizes the next, allowing nerve
Nerve and Muscle 1.pdf
1. Nerve and muscle cells are excitable tissues that can generate electrochemical impulses. In nerves, these impulses propagate signals along the axon when stimulated, whereas in muscles they cause contraction.
2. The resting membrane potential of these cells is maintained by ion concentration gradients and selective permeability of the membrane to ions like sodium, potassium, and chloride. At rest, the intracellular fluid is negatively charged relative to the extracellular fluid.
3. An action potential occurs when the membrane potential rapidly changes from the resting potential to a positive overshoot then back again. This is driven by changes in sodium and potassium conductance across the membrane.
Similar to Action potential (20)
Why do ion channels not function like open poresWhat is membrane .pdf
Why do ion channels not function like open poresWhat is membrane .pdf
BioT2C3-Action potential-transmission of impulse 2015-student.ppt
BioT2C3-Action potential-transmission of impulse 2015-student.ppt
B.Sc.(Micro+Biotech) II Animal & Plant Physiology Unit 4.2 Transmission of ne...
B.Sc.(Micro+Biotech) II Animal & Plant Physiology Unit 4.2 Transmission of ne...
More from K.M.College of Pharmacy, Madurai
Cerebrum
The document provides information about the human brain and cerebrum. It discusses that the brain is located in the skull and weighs approximately 1.4 kg on average. It is made up of gray and white matter and is divided into four lobes - frontal, parietal, temporal and occipital - each responsible for different functions. The cerebrum, located in the upper portion of the brain, is the largest part and is divided into right and left hemispheres. It controls vital functions like memory, intelligence, sensory perception, muscle movement, and higher mental processes.
Meninges, ventricle and CSF
This document discusses the nervous system, including the central nervous system (CNS) which includes the brain and spinal cord, and the peripheral nervous system. It describes the meninges - the three membranes (dura mater, arachnoid mater, and pia mater) that surround and protect the CNS. It also discusses the ventricles in the brain that contain cerebrospinal fluid (CSF), including the lateral, third and fourth ventricles. CSF is produced in the ventricles and circulates around the brain and spinal cord to provide nutrients and act as a shock absorber.
Neurotransmitters and receptor
This document discusses neurotransmitters and receptors in the nervous system. It defines neurotransmitters as chemical substances that transmit nerve impulses between neurons through synapses. Neurotransmitters are synthesized in the presynaptic neuron, packaged into vesicles, released into the synaptic cleft when calcium enters during an action potential, bind to receptors, and are then inactivated. The document also defines receptors as proteins that receive chemical signals and cause a cellular response. Receptors are classified as exteroceptors, which respond to external stimuli, or interoceptors, which respond to internal stimuli. Common neurotransmitters and receptor types are also listed.
Neuroglia, syapse
This document discusses the nervous system, specifically neuroglia and synapses. It defines neuroglia as supporting cells that provide metabolic and immune support to neurons. There are two main types of neuroglia - central neuroglia found in the central nervous system, and peripheral neuroglia found in the peripheral nervous system. Synapses are the junctions between neurons that transmit nerve impulses chemically or electrically. Synapses can be classified anatomically by their location on neurons or functionally based on their mode of impulse transmission. They allow for one-way conduction of signals between neurons and properties like synaptic delay, fatigue, and summation.
Neuron
This document provides information about the nervous system and neurons. It discusses that the nervous system controls all body functions and detects internal and external changes. It is comprised of neurons and neuroglia. Neurons consist of a cell body, dendrites, and axon. Neurons can be classified based on their structure as unipolar, bipolar, or multipolar. They can also be classified based on function as motor, sensory, or interneurons. The properties of nerve fibers include excitability, conductivity, all-or-none response, refractory period, summation, adaptation, and lack of fatigability.
ATP
This document summarizes adenosine triphosphate (ATP) and creatine phosphate. It discusses that ATP is an organic compound that provides energy for many cellular processes through substrate-level phosphorylation, which forms 10% of ATP, and oxidative phosphorylation in the mitochondria, which forms 90% of ATP. Creatine phosphate acts as a storage form of energy in muscles, providing a ready source of energy for intense muscle contraction in the first few seconds before oxidative phosphorylation can produce more ATP. The document also notes that creatinine is a breakdown product of creatine phosphate and creatine in muscles that is excreted in the urine, with serum creatinine levels indicating kidney function.
BMR
This document discusses the basic metabolic rate (BMR), which is defined as the minimum amount of energy required by the body to maintain life at complete physical and mental rest. It notes that several vital functions occur at a basal level, such as the working of organs, nerve impulse conduction, and ion transport. Normal BMR values for adults are provided as 1600 calories per day for men and 1400 calories per day for women. Several factors that can affect a person's BMR are described, including surface area, sex, age, physical activity level, hormones, environment, starvation, fever, and disease status.
GIT disorder
This document summarizes common disorders of the gastrointestinal (GIT) system, including gastroesophageal reflux disease (GERD), peptic ulcers, gastritis, diarrhea, constipation, Crohn's disease, and irritable bowel syndrome (IBS). It provides details on the causes, symptoms, and characteristics of each condition. The disorders can cause disruptions to the normally effective digestive system and result in issues like chest pain, heartburn, nausea, vomiting, abdominal pain, and changes in bowel movements. The document serves as an overview of several gastrointestinal tract disorders for educational purposes.
Chemical digestion of food
The document discusses the digestive system and the chemical digestion of food in the gastrointestinal tract (GIT). It describes the two types of digestion as mechanical and chemical. Mechanical digestion breaks down food into smaller pieces through processes like chewing and churning. Chemical digestion breaks down food into simple substances using enzymes. The three main nutrients absorbed are carbohydrates, proteins, and fats. Carbohydrates, proteins, and fats are broken down by specific digestive enzymes in different parts of the GIT into smaller molecules like glucose, amino acids, and fatty acids for absorption.
Small intestine digestion and pancreas
The document discusses the structure and functions of the small intestine. It is divided into three parts - the duodenum, jejunum, and ileum. The small intestine contains villi and intestinal glands that increase its surface area for absorption. Its functions include secreting enzymes to complete digestion, absorbing nutrients like proteins, carbohydrates and fats, and secreting hormones like CCK and secretin. Absorption mainly occurs in the jejunum by diffusion or active transport and reaches the bloodstream in the portal vein.
Structure and functions of liver
The liver is the largest gland in the human body, located in the upper right abdominal cavity beneath the diaphragm. It has four lobes and is made up of lobules that contain hepatocytes arranged in plates with blood sinusoids between them. The liver receives blood from the hepatic portal vein and hepatic artery, and filters toxins and produces bile, which is stored in the gallbladder and released into the small intestine after meals to aid in fat digestion. The liver performs many essential metabolic functions including carbohydrate, protein, and fat metabolism, hormone inactivation, and production of bile and proteins.
Small intestine and large intestine
The document provides information about the small intestine. It notes that the small intestine is around 6 meters long and divided into 3 parts - the duodenum, jejunum, and ileum. It describes the layers of the small intestine wall and discusses the villi and microvilli that line the intestine and help absorb nutrients. The document outlines the functions of the small intestine, including secreting enzymes to complete digestion, absorbing nutrients, and secreting hormones. It provides details on the absorption processes and locations in the small intestine for proteins, carbohydrates, fats, vitamins, and minerals.
Digestive system -Part II
This document provides an overview of the key parts and functions of the digestive system, including the mouth, pharynx, esophagus, and stomach. It describes the structures and roles of the mouth including teeth, tongue, and salivary glands. It then discusses the pharynx and esophagus, and their roles in swallowing and moving food to the stomach. Finally, it details the anatomy of the stomach including its layers, glands that secrete digestive juices, and temporary storage and chemical breakdown of food before it passes to the small intestine.
Digestive system -Basic introduction
The document provides an overview of the human digestive system. It discusses the main functions of digestion including ingestion, propulsion, digestion, absorption, and excretion. The primary digestive organs are identified as the mouth, pharynx, esophagus, stomach, and small and large intestines. The accessory digestive organs that help with digestion are the teeth, tongue, salivary glands, pancreas, liver, and gallbladder. Finally, it describes the common layers of the gastrointestinal tract wall which are the mucus, submucus, muscular, and serous layers from innermost to outermost.
Disorders of respiratory sysytem
This document summarizes several respiratory disorders:
Bronchial asthma causes difficult breathing and wheezing due to bronchiolar constriction from smooth muscle contraction in the bronchioles. Common symptoms include shortness of breath, chest tightness, and wheezing.
Mountain sickness occurs in people going to high altitude for the first time, developing symptoms like nausea, vomiting, increased heart rate, headache, fatigue and lack of sleep within a day before acclimating.
Decompression sickness occurs when a person returns rapidly from a high atmospheric pressure environment like deep sea diving to normal pressure. Symptoms include severe joint pain, numbness, temporary paralysis and muscle cramps.
Lungs volume and Capacities
This document discusses lung volumes and capacities. It defines four lung volumes: tidal volume, inspiratory reserve volume, expiratory reserve volume, and residual volume. It also defines four lung capacities that are combinations of the volumes: inspiratory capacity, vital capacity, functional residual capacity, and total lung capacity. It provides the normal values for each volume and capacity. Lung function tests measure these volumes and capacities to evaluate lung health and detect respiratory diseases. Spirometry uses a device called a spirometer to measure the volumes expired and inspired.
Physiology of respiration
This document discusses the physiology of respiration, including external and internal respiration. External respiration refers to the exchange of oxygen and carbon dioxide between the lungs and blood. Oxygen diffuses from the alveoli into the bloodstream, while carbon dioxide diffuses from the bloodstream into the alveoli. Internal respiration then involves the exchange of gases between the blood and tissues - oxygen diffuses from the blood into tissues, and carbon dioxide diffuses out of tissues and into the bloodstream. The document further explains the transportation of oxygen from the lungs to tissues via hemoglobin in red blood cells, and the transportation of carbon dioxide from tissues back to the lungs, where it is removed from the body.
Regulation of respiration
The document summarizes the nervous and chemical mechanisms that regulate respiration. There are two main mechanisms:
1. The nervous mechanism involves respiratory centers in the medulla oblongata and pons that receive input from afferent nerves and control respiration through efferent nerves that stimulate the diaphragm and intercostal muscles.
2. The chemical mechanism senses changes in blood gases through central and peripheral chemoreceptors. Central chemoreceptors in the brain stem detect increased carbon dioxide, while peripheral chemoreceptors in the carotid and aortic arteries detect low oxygen levels. Both trigger the respiratory centers to increase breathing rate.
Mechanism of Respiration
The document summarizes the physiology of respiration and the mechanism of breathing. It describes that breathing consists of two phases: inspiration and expiration. Inspiration is the active process of inhaling air which involves contraction of the diaphragm and intercostal muscles to enlarge the thoracic cavity and decrease lung pressure, drawing air in. Expiration is the passive process of exhaling air which involves relaxation of these muscles, shrinking the thoracic cavity so lung pressure exceeds atmospheric pressure, expelling air out.
Respiratory system
The respiratory system allows for gas exchange between the lungs and cells of the body. It includes the nose, pharynx, larynx, trachea, bronchi, bronchioles, lungs and alveoli. The nose and pharynx warm and humidify inhaled air before it reaches the lungs. In the lungs, oxygen passes from the alveoli into the bloodstream and carbon dioxide passes out. This allows for cellular respiration to occur.
More from K.M.College of Pharmacy, Madurai (20)
Recently uploaded
Integrating Ayurveda into Parkinson’s Management: A Holistic Approach
Explore the benefits of combining Ayurveda with conventional Parkinson's treatments. Learn how a holistic approach can manage symptoms, enhance well-being, and balance body energies. Discover the steps to safely integrate Ayurvedic practices into your Parkinson’s care plan, including expert guidance on diet, herbal remedies, and lifestyle modifications.
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotes
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
vonoprazan A novel drug for GERD presentation
Vonoprazan, a new potassium acid channel blocker used in the conditions of GERD and gastric ulcer, duodenal ulcer ....
share - Lions, tigers, AI and health misinformation, oh my!.pptx
• Pitfalls and pivots needed to use AI effectively in public health
• Evidence-based strategies to address health misinformation effectively
• Building trust with communities online and offline
• Equipping health professionals to address questions, concerns and health misinformation
• Assessing risk and mitigating harm from adverse health narratives in communities, health workforce and health system
REGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptx
It includes regulation of combination products and medical devices. FDA and industry liaisons.
Osteoporosis - Definition , Evaluation and Management .pdf
Osteoporosis is an increasing cause of morbidity among the elderly.
In this document , a brief outline of osteoporosis is given , including the risk factors of osteoporosis fractures , the indications for testing bone mineral density and the management of osteoporosis
Ketone bodies and metabolism-biochemistry
This slide consists of all the topics of ketone . This can be used for exam purpose for writing about Diabetic keto acidosis etc . Thank you
Identifying Major Symptoms of Slip Disc.
Our backs are like superheroes, holding us up and helping us move around. But sometimes, even superheroes can get hurt. That’s where slip discs come in.
Histololgy of Female Reproductive System.pptx
Dive into an in-depth exploration of the histological structure of female reproductive system with this comprehensive lecture. Presented by Dr. Ayesha Irfan, Assistant Professor of Anatomy, this presentation covers the Gross anatomy and functional histology of the female reproductive organs. Ideal for students, educators, and anyone interested in medical science, this lecture provides clear explanations, detailed diagrams, and valuable insights into female reproductive system. Enhance your knowledge and understanding of this essential aspect of human biology.
Hemodialysis: Chapter 4, Dialysate Circuit - Dr.Gawad
- Video recording of this lecture in English language: https://youtu.be/kqbnxVAZs-0
- Video recording of this lecture in Arabic language: https://youtu.be/SINlygW1Mpc
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Recently uploaded (20)
Integrating Ayurveda into Parkinson’s Management: A Holistic Approach
Integrating Ayurveda into Parkinson’s Management: A Holistic Approach
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotes
Promoting Wellbeing - Applied Social Psychology - Psychology SuperNotes
share - Lions, tigers, AI and health misinformation, oh my!.pptx
share - Lions, tigers, AI and health misinformation, oh my!.pptx
Ear and its clinical correlations By Dr. Rabia Inam Gandapore.pptx
Ear and its clinical correlations By Dr. Rabia Inam Gandapore.pptx
REGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptx
REGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptx
Vestibulocochlear Nerve by Dr. Rabia Inam Gandapore.pptx
Vestibulocochlear Nerve by Dr. Rabia Inam Gandapore.pptx
Osteoporosis - Definition , Evaluation and Management .pdf
Osteoporosis - Definition , Evaluation and Management .pdf
Muscles of Mastication by Dr. Rabia Inam Gandapore.pptx
Muscles of Mastication by Dr. Rabia Inam Gandapore.pptx
Hemodialysis: Chapter 4, Dialysate Circuit - Dr.Gawad
Hemodialysis: Chapter 4, Dialysate Circuit - Dr.Gawad
Action potential
- 1. Human Anatomy and Physiology-II Nervous system (Action potential) Mr N.JEGAN Associate Professor K.M.COLLEGE OF PHARMACY. MADURAI.
- 2. Action potential All cells for example muscle cells , neuron cells( nerve cells ) and cardiac cells posses electrical excitability, the ability to response to a stimulus and convert it into an action potential.
- 3. Nerve impulse A signal transmitted along a nerve fibre. It consists of a wave of electrical depolarization that reverses the potential difference across the nerve cell membranes.
- 4. Action potential-Definition An electrical signal that propagates along the surface of the membrane of a neuron (nerve cell ) due to the movement of ions ( sodium & potassium) between interstitial fluid and the inside of a neuron through specific ion channels in its plasma membrane.
- 6. MEMBRANE POTENTIAL An electrical potential difference across the membrane ► It is like voltage stored in battery ► In living cells the flow of ions rather than electrons constitutes the electrical current/ signal. ► The main path for current to flow across the membrane are through ion channels.
- 7. ION CHANNELS ► Ion channels open and close due to presence of gates ► When ion channels are opened, they allow specific ions to move across the plasma membrane, down their electrochemical gradient. ► As ions move , they create a flow of electrical current that can charge the membrane potential.
- 8. GENERATION OF ACTION POTENTIAL The principal ions involved are: 1.sodium (Na+) the main extracellular cation 2.potassium (K+) the main intracellular cation.
- 9. Action Potential-Phase It occur in four phase 1.Resting potential 2.Depolarizing Phase 3. Repolarizing phase 4. Repolarizing continue
- 10. Resting potential 1.All voltage gated Na+ and K + channel closed 2.Small buildup of negative charge along the inside the surface of membrane and equal amount of positive charge along the outside the membrane.
- 11. Depolarizing Phase 1.When membrane potential reach axon, Na+ Channel 2. Na+ ion enter in to neuron through this channel 3. buildup of positive charge along the inside the surface of membrane
- 12. Repolarizing phase 1. Na+ Channel inactivation close the channel. 2. K+ channel open 3. Some K+ ion leave the neuron 4. Negative charge begin to buildup of along the inside the surface of membrane.
- 13. Repolarizing phase continue 1. K+ outflow continue , more K+ ion leave the neuron. 2. More negative charge buildup of along the inside the surface of membrane. 3.Na+ channel inactivation gate open 4.Return to resting stage when K+ gates close.
- 16. GENERATION OF ACTION POTENTIAL ALONG AXON
- 17. Refractory period It refers to the amount of time it takes for an excitable membrane to be ready to respond to a second stimulus once it returns to a resting state.
- 18. Thank you