Introduction to Cellular Biophysics, Volume 2
- From membrane transport to neural signalling
- Armin Kargol
- December 2019
All living matter is comprised of cells, which are small compartments isolated from the environment by a cell membrane and filled with concentrated solutions of various organic and inorganic compounds. Some organisms are single-cell, where all life functions are performed by that cell. Others have groups of cells, or organs, specializing in one particular function. The survival of the entire organism depends on all of its cells and organs fulfilling their roles.
Cells are seen differently by biologists, chemists, or physicists. Biologists concentrate their attention on cell structure and function. What the cells consist of? Where are its organelles? What function each organelle fulfils? From a chemists' point of view, a cell is a complex chemical reaction chamber where various molecules are synthesized or degraded. From a physics standpoint, however, some of the fundamental questions involve the physical movement of all these molecules between organelles within the cell, their exchange with the extracellular medium, as well as electrical phenomena resulting from such transport.
The aim of this book is to look into the basic physical phenomena occurring in cells. These physical transport processes facilitate chemical reactions in the cell and various electrical effects, and that, in turn, leads to the biological functions necessary for the cell to satisfy its role in the mother organism. Ultimately, the goals of every cell are to stay alive and to fulfil its function as a part of a larger organ or organism. The first volume of this book is an inventory of physical transport processes occurring in cells, and this volume provides a closer look at how complex biological and physiological cell phenomena result from these very basic physical processes.
Armin Kargol studied physics and mathematics at the University of Wrocław, Poland, and at Virginia Tech, USA, where he earned a PhD in physics. He was a postdoctoral fellow at the Institute for Mathematics and Its Applications (IMA) in Minneapolis and at Tulane University in New Orleans. Since 2003 he has worked at Loyola University New Orleans where he is currently a professor of physics and the Rev. James C Carter, S J, Distinguished Professor in experimental physics.
Table of Contents
2.1 From membrane biophysics to cell physiology
2.2 Review of cell structure and function
2.2.1 Cell biology
2.2.2 Cell biochemistry
2.2.3 Cell biophysics
3 Cell homeostasis
3.1 What is cell homeostasis?
3.1.1 Primary volume response
3.1.2 Cell volume homeostasis
3.2 Regulatory volume responses
3.2.1 Mechanisms of regulatory volume changes
3.2.2 Volume sensing
3.3 Models of a primary response
3.3.1 Semipermeable membrane
3.3.2 One permeable and one impermeable solute
3.4 Models of volume regulation
3.4.1 Pump-leak model
3.4.2 Steady-state solution to pump-leak model
4 Homeostasis and transport in epithelial cells
4.1 What is the epithelium?
4.2 Transport in epithelial layers
4.3 Models of epithelial transport
4.3.1 Epithelium as a single, homogeneous barrier
4.3.2 Curran model
4.3.3 Standing gradient model
4.3.4 Advanced models of epithelial transport and homeostasis.
5 Electrical properties of neurons
5.1 Biology of a neuron
5.2 Early neurophysiology
5.3 Resting potential revisited
5.4 Electrical equivalent circuit for a cell
5.5 The cable model
5.5.1 Derivation of the cable equation
6 Neuron excitability
6.1 Action potentials
6.1.1 The discovery of action potentials
6.1.2 Properties of action potentials
6.2 Hodgkin-Huxley (HH) model
6.2.1 Experimental basis
6.2.2 Model assumptions
6.2.3 The equivalent circuit and the current equation
6.2.4 Variable membrane conductance
6.2.5 HH model equations
6.2.6 HH model analysis
6.2.7 HH model meets ion channels
6.3 Simplified models
6.3.1 Phase-space analysis. A harmonic oscillator example.
6.3.2 Reduced HH model – the fast-slow phase plane
6.4 Propagation speed. Saltatory conduction in neurons
7 Synaptic transmission
7.1 What is a synapse?
7.2 Chemical synapses
7.2.1 Action potential in presynaptic membrane. Calcium release.
7.2.2 Neurotransmitter release and diffusion in the synaptic cleft
7.2.3 Neurotransmitter receptors. Action potentials in postsynaptic membrane.
7.2.4 Effect of drugs on synaptic transmission and neural computing
7.3 Electrical synapses
7.3.1 Gap junctions
7.3.2 Properties of electrical synapses
Paperback ISBN: 9780750330176
Ebook ISBN: 9781643277554
Publisher: Morgan & Claypool Publishers