Recommandé
Contenu connexe
Tendances
Tendances (20)
Similaire à Sistema nervioso y neuronas
Similaire à Sistema nervioso y neuronas (20)
Dernier
Dernier (20)
Sistema nervioso y neuronas
- 1. SISTEMA NERVIOSO 1º Parte Chapter 33
- 6. El axón gigante de calamar
- 9. regulan [ ] del ion potasio, pueden proliferar para formar tejido cicatril en caso de lesión del SNC está formada por células fagocitarias que ingieren y metabolizan material extraño
- 16. Una célula nerviosa (Neurona) Chapter 33 Cuerpo celular Dendritas Axon de otras neuronas Axon Vaina de mielina ( aisla al axón y acelera conducción ) Dendritas de otras neuronas
- 17. Chapter 33 Los cuerpos o somas de las células nerviosas frecuentemente se encuentran agrupados en ganglios (SNP) y en núcleos (SNC) Los axones se agrupan formando nervios (principalmente en el SNP) y haces o fascículos (SNC)
- 18. Estructura de un nervio Chapter 33
- 26. Sucesos eléctricos durante un Potencial de acción Chapter 33 Potencial de reposo Líquido Extracelular (sin carga) umbral PPSI PPSE 1 2 3 Potencial de acción 80 40 0 -40 -80 Potencial registrado (millivolts) Tiempo (milisegundos)
- 30. Neurona sin estimulación Chapter 33 (Líquido extracelular) (Citoplasma Neuronal, cargado negativamente) (Membrana Neuronal) Org - Na + Org - Org - Org - Org - K + K + K + K + K + Cl - Cl - Cl - Cl - Na + Na + Na + Canal Potasio Canal Sodio (cerrado)
- 32. Iniciación Potential de Acción Chapter 33 Org - K + K + K + Cl - Na + Na + K + Na + Na + Na + (Líquido Extracelular) (Citoplasma Neuronal, cargado positivamente) (cargado negativamente) Org - Na + Org - Org - K + K + Cl - Na + K + K + K + K + Na + Na + Cl -
- 33. Iniciación de Potencial de Accion Chapter 33 Potencial de acción Líquido extracelular
- 34. Propagación de Potencial de Acción Chapter 33 Potencial de acción Líquido extracelular
- 35. Estructura y Operación de la Sinápsis Chapter 33 1 Iniciación de un potencial de acción 2 Potencial de Acción llega al terminal sináptico de la neurona presináptica 3 Vesicula Sináptica libera neurotransmisor 4 Receptor se une al neurotransmisor y abre canal iónico
- 36. Señales según intensidad de estímulos Chapter 33 Toque Suave Presión Media Presión Fuerte Un toque suave Descarga lenta Tranquilidad Descarga más rápida Tranquilidad Descarga aún más rápida Descarga lenta Unos cuántos potenciales de acción en una neurona Estimulación de un receptor, que se dispara con mayor rapidez Estimulación de dos receptores, uno se dispara muy rápido y el otro lento 1 1 2 1 2 (a) 1 2 (b) 1 2 (c) 1 2 2
Notes de l'éditeur
- Biology: Life on Earth (Audesirk) Chapter 33
- Biology: Life on Earth (Audesirk) Chapter 33 Using the giant axon of the squid, British physiologists Bernard Katz, Alan Hodgkin, and Andrew Huxley pushed electrodes (thin wires or narrow glass tubes filled with conducting solution) inside the axon. These electrodes were connected to voltmeters to record the electrical potential difference between the inside and outside of the axon, about –70 millivolts.
- Biology: Life on Earth (Audesirk) Chapter 33 A nerve cell, showing its specialized parts and their functions.
- Biology: Life on Earth (Audesirk) Chapter 33 A recording (by oscilloscope) of the electrical events in a nerve cell. The resting potential is about 60 millivolts negative with respect to the outside. 1) When a PSP stimulates the cell to threshold, membrane channels permeable to sodium open and sodium enters the cell, powered by diffusion and by electrical attraction; 2) the inside of the cell becomes positively charged. 3) Shortly thereafter, other membrane channels permeable to potassium open and potassium leaves, driven by diffusion and electrical repulsion from the now-positive inside of the cell, until the resting potential is reestablished.
- Biology: Life on Earth (Audesirk) Chapter 33 The ionic composition of a neuron’s cytoplasm is significantly different from that of the extracellular fluid. The neuron maintains high concentrations of K+ and large organic ions (Org– ); the extracellular fluid is high in Na+ and Cl– .
- Biology: Life on Earth (Audesirk) Chapter 33 An unstimulated neuron
- Biology: Life on Earth (Audesirk) Chapter 33 Initiation of an action potential
- Biology: Life on Earth (Audesirk) Chapter 33 Initiation of an action potential
- Biology: Life on Earth (Audesirk) Chapter 33 Propagation of an action potential
- Biology: Life on Earth (Audesirk) Chapter 33 The synaptic terminal contains numerous vesicles that enclose a neurotransmitter for which the postsynaptic neuron has membrane receptors. When an action potential enters the synaptic terminal of the presynaptic neuron, the vesicles dump their neurotransmitter into the gap between the neurons. The neurotransmitter diffuses rapidly across the space, binds to postsynaptic receptors, and causes ion channels to open. Ions flow through these open channels, causing a postsynaptic potential in the postsynaptic cell.
- Biology: Life on Earth (Audesirk) Chapter 33 The intensity of a stimulus is signaled by the rate at which individual neurons produce action potentials and by the number of neurons that do so. Consider two touch receptors that have endings in adjacent patches of skin. (a) A gentle touch elicits only a few action potentials from one sensory neuron but none from another. (b) Moderate pressure stimulates only one receptor, which now fires faster, informing the brain that the touch is more intense than before. (c) Strong pressure activates both receptors, firing one very fast and the other more slowly, thus signaling that the pressure is very intense and localized over the fastest-firing receptor.