Intro to Phys I
Tissues : groups of cells with similar structure and specialized function. The four types of
tissues are CEMN- connective, epithelial, nervous, muscle.
Muscle tissues contract to generate forces: three type of muscle tissues are skeletal, smooth
Nervous tissues transmit electrical impulses
Epithelial tissues exchange materials between the cell and its environment. Organized into
sheets and secretory glands. (exo and endocrine glands)
Connective tissue connects supports and anchors various body parts: few cells dispersed with
an abundance of extracellular material
Organs: two or more types of primary tissues that function together to perform a particular
function or functions – stomach has epithelial lining, smooth walls, nervous contractions and
connective tissue to bind all the above.
Human body has 11 systems
Homeostasis: maintaining a relatively stable internal environment
Homeostatic factors: concentration of nutrient molecules, concentration of O2 and CO2,
concentration of waste products, pH, concentration of water salt and other electrolytes, volume
and pressure, temp
Carbs: defined by structure- humans digest starch not cellulose. We store as glycogen
Lipids: insoluble in h20- fatty acids triglycerides cholesterols steroids (not dense and surplus
nrgy) complex lipid examples: cell membranes (cholesterol) and hormones (cortisol) *lipids do
have some amino acids but not much*
Proteins: defined by structure – enzymes and amino acids. 20 common amino acids, not just 20.
Main structure of cells.
Question: what is an essent