Membrane Permability Flashcards
Levels of Organization
Chemical->Cellular->Tissue->Organ->Organ system-> Organism
Epithelial Tissue
epidermis, inner lining of digestive tract, skin, liver, and other glands
Connective Tissue
tendons and ligaments, cartilage and bone, blood
Muscular Tissue
Skeletal muscles, heart (cardiac muscle), walls of viscera (smooth muscle)
Nervous Tissue
brain, spinal cord, other nerves
Percent of Tissues
Muscle: 50%
Connective: 45%
Epithelial: 3%
Neural: 2%
Homeostasis
The maintenance of a stable internal environment
Body Fluids and Compartments percentages
60% of total body weight is water: 42 kg (or liters)
2/3 of body water is intracellular: 28 liters
1/3 of body water is extracellular: 14 liters
80% of extracellular fluid is interstitial: 11 liters
20% of extracellular fluid is plasma: 3 liters
Predominant ICF Electrolytes
K+ and HPO4
Predominant ECF Electrolytes
Na+ and Cl-
Purpose of Cholesterol in the Membrane
Helps to stiffen and stabilize the bilayer.
- Less fluid
- Less permeable
Six major functions of membrane proteins
Transport Enzymatic activity Signal transduction Cell-cell recognition Intercellular joining Attachment to the cytoskeleton and extracellular matrix (ECM)
Diffusion
Passive molecular movement from an area of higher concentration to an area of lower concentration (Gases, small inorganic ions and small molecules, lipid-soluble materials)
Fick’s First Law of Diffusion
the concept that a solute will move from a region of high concentration to a region of low concentration across a concentration gradient.
Factors that influence diffusion
Distance Size Temperature Concentration Gradient Electric Forces
