Physiology Ref Textbook of Medical Physiology 13 th

Physiology Ref. : Textbook of Medical Physiology. 13 th ed: 47 -102, 12 th. Ed. 11 th edition By, Guyton and Hall.

Physiology Introduction Cell physiology Membrane physiology Excitable tissues Nerve Muscle

Fig. 01

Fig. 01. 02

NEGATIVE FEEDBACK

POSITIVE FEEDBACK

Fig. 03. 01

Fig. 03. 02

Fig. 03

Tight Junction

Gap Junction

Desmosome (Adhering Junction)

Transport across Plasma Membranes

Transport across Plasma Membranes

Transport across Plasma Membranes

Diffusion through lipid bilayer • • • CO 2 NO Steroid Hormones Monoglycerides

Diffusion through Biological Membranes

Simple Diffusion

Fick’s Law • J = P. ∆C • P = D. A/∆X • J = D. A. ∆C/∆X J = Flux (Rate of diffusion) P = Permeability D = Diffusion Coefficient A = Surface area C = Concentration X = Membrane thickness

Simple Diffusion

Simple Diffusion

Facilitated Diffusion

Facilitated Diffusion

Facilitated Diffusion • • Aminoacids Glucose Galactose Fructose

Osmosis

Osmosis

Osmotic pressure

Van’t Hoff’s Law π = RTC π : osmotic Pressure R = Gas constant T = Absolute Temprature C = Concentration

Tonicity of solution

Hypotonic (cell swells) Isotonic (no change) Figure 25 -5; Guyton and Hall Hypertonic (cell

Active Transport Mechanisms • Primary active transport • Secondary active transport • Vesicular transport

Types of Pumps • • Na+/K+ pump H+/K+ pump Ca++ pump

Na+ / K+ Pump

The importance of pumps for cell functions

Transport is Controlled by -Activation of receptors - Changing activity of certain enzymes

Control of Transport

Receptors & Enzymes

Receptors & Channels

Receptors & G proteins

Control of Exocytosis