Physiology The science that deals with the function of different parts of the body that keeps the human alive

The body is Group of cells Group of cells form a tissue Group of tissues form an organ Group of organs form a system that perform a specific function

Homeostasis Reference ( GUYTON AND HALL ) Chapter 1 (Pages 3-5)

Total body water (TBW) TBW compartments Intracellular fluid (ICF) Extra cellular fluid (ECF) Composition of ICF & ECF (m Eq/L) Reference ( GUYTON AND HALL ) Chapter 1 (Pages 3-5) Reference ( GUYTON AND HALL ) Chapter 1 (Pages 3-5) Reference ( GUYTON AND HALL ) Chapter 25 (Pages )

Cell membrane

Lipid bi-layer Peripheral spherical part Central linear part Cell membrane proteins Integral protein ( spanning protein) Peripheral proteins Membrane Carbohydrate Reference ( GUYTON AND HALL ) Chapter 1 (Pages 13-14)

barrier to water and water-soluble substances ions glucose H2OH2O urea Lipid Bilayer: CO 2 O2O2 N2N2 halothane

provide “specificity” to a membrane provide “function” K+K+ ion channelscarrier proteins Proteins:

Types of ion channels Leak channels: A- Sodium leak channels B- Potassium leak channels Gated channels: 1-Voltage gated 2- Ligand gated Reference ( GUYTON AND HALL ) Chapter 4 (Pages 45-49)

Na + in out Na + and other ions Ion Channels

Voltage gated channels Two Types: 1- Voltage gated sodium channel : 2- Voltage gated Potassium channels: Reference ( GUYTON AND HALL ) Chapter 4 (Pages 45-49)

Voltage gated channels

Types of transport Active transport: Passive transport: ( diffusion) Diffusion types Simple diffusion: Facilitated diffusion Reference ( GUYTON AND HALL ) Chapter 4 (Pages 45-56)

Diffusion Active Transport occurs down a concn. gradient no mediator or involves a “channel” or “carrier” no additional energy occurs against a concn. gradient involves a “carrier” requires ENERGY Figure 4-2; Guyton & Hall (page 46)

(a) lipid-soluble molecules (O2 & CO2) move readily across the membrane (rate depends on lipid solubility) (b) water-soluble molecules (ions) cross via channels or pores (a) (b) Simple Diffusion

Facilitated Diffusion (also called carrier mediated diffusion) Figure 4-8; Guyton & Hall (page 49)

Differences between Simple & facilitated diffusion

Factors that affect the net rate of diffusion: 1. Concentration difference (C o -C i ) net diffusion  D (C o -C i ) Figure 4-9; Guyton & Hall (page 50)

A B Net Diffusion Can a molecule diffuse from side B to side A?

2. Pressure difference Figure 4-9; Guyton & Hall (page 50) 3- Temperature. 4- Surface area of diffusion membrane. 5- Number of protein channels. 6- Lipid solubility of the substance. 7- Thickness of the diffusion membrane. 8- Molecular weight of the diffusing substances.

Osmosis: - Net diffusion of water - Osmosis occurs from pure water toward a water/salt solution. Water moves down its concn gradient. Figure 4-10; Guyton & Hall (page 51) Reference ( GUYTON AND HALL ) Chapter 4 (Pages 45-65) Reference ( GUYTON AND HALL ) Chapter 25 (Pages )

Osmotic Pressure: the amount of pressure required to counter osmosis Figure 4-11; Guyton & Hall (page 51) Reference ( GUYTON AND HALL ) Chapter 4 (Pages 45-65) Reference ( GUYTON AND HALL ) Chapter 25 (Pages )

Active transport Types of active transport 1- Primary active transport 2- Secondary active transport Secondary active transport C0-transport (Symport) Counter-transport (Antiport) Reference ( GUYTON AND HALL ) Chapter 4 (Pages 45-56)

Primary active transport Sodium- Potassium pump

Secondary Active Transport Examples: inside outside 1. Co-transport (symport)

2. Counter-transport (anti-porters) Examples: outside inside

Exocytosis

ENDOCYTOSIS : two main types : PHAGOCYTOSIS : (CELL EATING): PINOCYTOSIS : (CELL DRINKING): Reference ( GUYTON AND HALL ) Chapter 4 (Pages 45-65)