Physiology chapter 5

Says that if the amount of a substance in the body is to rmain constant, any input must be offset by an equal loss

• Is the rate at which a material is removed from the blood by excreation, metabolism or both
• ex: Liver kidneys lungs and skin all clear substances from the blood

Most solutes are concentrated in either ine compartment or the other

Cations and anions are not distributed equally between the body compartments

Water moves freely between the cells and the extracellular fluid

Water always moves from hyposmotic to hyperosmotic

can diffuse through the phospholipid layer. Less lipid soluble molecules require the assistance of a membrane protein to cross the membrane

Does not require the input of energy

• is the passive movement of molecules down a chemical concentration gradient from an area of higher concentration to lower concentration.
• Net movement stops when the system reaches an equilibrum but molecular movement continues.
• Is slow over long distances is directley related to temp and inversley related to molecular size

• passive movment of molecules from and high concentration to a low concentration across the membrane
• Its directly related to proportional membrane surface, concentration gradiant and permeability and inversley proportional to membrane thickness

• Structual proteins: maintian cell shape and form cell junctions
• Membrane associated enzymes: Catalyze chemical reactions and help transfer signals across the membrane
• Receptor proteins: are part of the bodys signaling system
• Transport proetins: move many molecules into or out of the cell

form water filled channles that link the intracellular and extracellular compartments

Protein mediated diffusion. (Help)

• moves molecules against the concentration gradiant and requires an outside sorce of energy
• Direct: Energy comes from ATP
• Indirect: Uses potentioal energy stored in the concentration gradiant indirectly driven by ATP

The most important primary active transporter. 3 Na+ out of cell 2 K+ into cell.

Large molecules are brought in this way. Materials leave by exocytosis

The movement of water across the membrane in responce to a concentration gradiant

Number of particles per liter in a solution

Cell volume change when it is placed in a solution

cells shrink

Cells swell

No change cells are at equalibrium