Exchange of ions across membrane during AP is far to small to significantly affect concentration...

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Page 1: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 2: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.

Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions that enter or leave the neuron during 1 AP in squid giant axon is 4pmol/cm2, the number of Na+ ions in a volume of axons covered by 1 cm2 of membrane is 3 million times this amount. Comparable to effect on weight of diesel locomotive of having mouse climb aboard, thus thousands of APs can be generated even in small neuron before ion balance significantly affected

Page 3: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 4: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 5: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 6: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 7: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 8: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 9: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 10: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.

proprietàdei

recettori

proprietàdella

membrana

Page 11: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 12: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 13: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 14: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 15: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 16: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.
Page 17: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.

Sinapsi elettriche: implicazioni funzionali

1. Rapidità della trasmissione

2. Sincronizzazione

3. Accoppiamento metabolico

COMPORTAMENTI STEREOTIPATI E SINCRONIZZATI CONTROLLO MOVIMENTI SINCRONI

Page 18: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.

Sinapsi elettricheSinapsi elettriche

•• Nessun ritardo sinaptico (rapidità)

•• Trasmissione potenzialmente bidirezionale

•• Possono essere trasmesse sia depolarizzazioni sia iperpolariz-zazioni presinaptiche.

•• Nessuna inversione di polarità del segnale di input

COMPORTAMENTI STEREOTIPATI E SINCRONIZZATI

CONTROLLO MOVIMENTI SINCRONI

Sinapsi chimicheSinapsi chimiche

•• Ritardo sinaptico

•• Trasmissione sempre uni dire-zionale

•• Solo una depolarizzazione presinaptica è efficace per la trasmissione

•• Possibile un’inversione di polarità dello stimolo di input

COMPORTAMENTI COMPLESSIMODULABILE: POTENZIATA o

DEPRESSA

Page 19: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.

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sono necessari per visualizzare quest'immagine.

Page 20: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.

Un modello di sinapsi elettrica: la sinapsi Un modello di sinapsi elettrica: la sinapsi motoria gigante del gamberomotoria gigante del gambero

Accoppiamento elettrico nell’Aplysia californica

Page 21: Exchange of ions across membrane during AP is far to small to significantly affect concentration gradients across the membrane. The net number of ions.

L’accoppiamento metabolico dovuto a L’accoppiamento metabolico dovuto a gap gap junctionjunction: astrociti: astrociti

Rilascio di glutammatoRilascio di glutammato

¯̄

attivazione di recettori glutammatergici astrocitari di tipo metabotropicoattivazione di recettori glutammatergici astrocitari di tipo metabotropico

¯̄

rilascio di Ca2+ IP3-mediatorilascio di Ca2+ IP3-mediato

¯̄

amplificazione del segnale di Ca2+ amplificazione del segnale di Ca2+

¯̄

propagazione del segnale di Ca2+ via gap junctionpropagazione del segnale di Ca2+ via gap junction

¯̄

attivazione delle NOS - produzione di NOattivazione delle NOS - produzione di NO

¯̄

vasodilatazionevasodilatazione


Movement Across the Membrane

Movement Across the Membrane

TRANSPORT ACROSS CELL MEMBRANE-II

TRANSPORT ACROSS CELL MEMBRANE-II

Calcium ions promote membrane fusion by forming negative ... · 4/29/2020  · Calcium ions promote membrane fusion by forming negative-curvature inducing clusters on speci c anionic

Calcium ions promote membrane fusion by forming negative ... · 4/29/2020  · Calcium ions promote membrane fusion by forming negative-curvature inducing clusters on speci c anionic

MOVEMENT ACROSS MEMBRANES - web.calpoly.edubio/EPL/pdfs/SampleLectureBIO361.pdf · 3. Inorganic ions: low permeability across membrane, but can diffuse passively through cell membranes

MOVEMENT ACROSS MEMBRANES - web.calpoly.edubio/EPL/pdfs/SampleLectureBIO361.pdf · 3. Inorganic ions: low permeability across membrane, but can diffuse passively through cell membranes

Resting Membrane Potential Review Recall there is an uneven distribution of charged substances (mainly ions) across the cell membrane of every cell in.

Resting Membrane Potential Review Recall there is an uneven distribution of charged substances (mainly ions) across the cell membrane of every cell in.

Transport of Materials Across the Cell Membrane · 2019-02-28 · e) 2+Ca ions can move through the cell membrane by simple diffusion. ___ f) Simple diffusion may use a channel protein

Transport of Materials Across the Cell Membrane · 2019-02-28 · e) 2+Ca ions can move through the cell membrane by simple diffusion. ___ f) Simple diffusion may use a channel protein

keystone packet part 1 - North Allegheny School District · density across the cell membrane Facilitated Diffusion: Transport proteins in the cell membrane help ions and polar molecules

keystone packet part 1 - North Allegheny School District · density across the cell membrane Facilitated Diffusion: Transport proteins in the cell membrane help ions and polar molecules

a8) Transport Across the Membrane

a8) Transport Across the Membrane

Transport of Ions and Small Molecules Across Cell Membranes Objectives: Review how membrane transport is accomplished with the help of proteins – facilitated.

Transport of Ions and Small Molecules Across Cell Membranes Objectives: Review how membrane transport is accomplished with the help of proteins – facilitated.

The Sodium-Potassium Pump Consists of molecules in the neuronal membrane Exchanges NA+ ions for K+ ions across the membrane Requires energy for active.

The Sodium-Potassium Pump Consists of molecules in the neuronal membrane Exchanges NA+ ions for K+ ions across the membrane Requires energy for active.

Cellular Transport Transport across the Membranecontains transport proteins that help transport ions across the membrane. 4. When substances attain equal distribution over ... •Capillaries

Cellular Transport Transport across the Membranecontains transport proteins that help transport ions across the membrane. 4. When substances attain equal distribution over ... •Capillaries

Cell Membrane Function (Movement Across the Cell Membrane)

Cell Membrane Function (Movement Across the Cell Membrane)

HANDOUT - Cell Transport Packet · 11. active transport will remove ___ ions, while taking in potassium ions 12. channel ___ can help move things across the membrane 16. organelle

HANDOUT - Cell Transport Packet · 11. active transport will remove ___ ions, while taking in potassium ions 12. channel ___ can help move things across the membrane 16. organelle

Molecular Motors...Types of Motors 1. Pump - Membrane protein that transports ions and small molecules across the membrane. 2. Rotary Motor - Membrane-bound structure having a spinning

Molecular Motors...Types of Motors 1. Pump - Membrane protein that transports ions and small molecules across the membrane. 2. Rotary Motor - Membrane-bound structure having a spinning

Negative Ions Enhance Survival of Membrane Protein Complexes · J. Am. Soc. Mass Spectrom. (2016) 27:1099Y1104 Negative Ions Enhance Survival of Membrane Protein Complexes Idlir Liko,

Negative Ions Enhance Survival of Membrane Protein Complexes · J. Am. Soc. Mass Spectrom. (2016) 27:1099Y1104 Negative Ions Enhance Survival of Membrane Protein Complexes Idlir Liko,

Iontophoresis Iontophoreis n Introduction of Ions Into The Body Using Direct Electrical Current n Transports Ions Across A Membrane Or Into a Tissue.

Iontophoresis Iontophoreis n Introduction of Ions Into The Body Using Direct Electrical Current n Transports Ions Across A Membrane Or Into a Tissue.

MOVEMENT ACROSS MEMBRANES MEMBRANE STRUCTURE ...

MOVEMENT ACROSS MEMBRANES MEMBRANE STRUCTURE ...

Chemistry Membranes Transport across membrane … · Chemistry Membranes Transport across ... protects plasma membrane from ... Transport of substances across membrane passive transport

Chemistry Membranes Transport across membrane … · Chemistry Membranes Transport across ... protects plasma membrane from ... Transport of substances across membrane passive transport

Active Transport - OpenStax CNX · 2016. 11. 17. · active transport moves ions across a membrane and creates a di erence in charge across that membrane. The primary active transport

Active Transport - OpenStax CNX · 2016. 11. 17. · active transport moves ions across a membrane and creates a di erence in charge across that membrane. The primary active transport

TRANSPORT OF IONS AND SMALL MOLECULES ACROSS CELL …kbp-srmc.yolasite.com/resources/Chapter 7.pdf · MOLECULES ACROSS CELL MEMBRANES T he plasma membrane is a selectively permeable

TRANSPORT OF IONS AND SMALL MOLECULES ACROSS CELL …kbp-srmc.yolasite.com/resources/Chapter 7.pdf · MOLECULES ACROSS CELL MEMBRANES T he plasma membrane is a selectively permeable