bio chapter 4

the ______ ________ seperates the internal environment of the cell from its external environment

the plasma membrane _________ the entrance and exit of _________ into and out of the cell

the steady internal environment maintained is called:

• equilibrium

• homestatic

• homeostasis

homeostasis is the maintenance of normal ________ conditions in a cell or organism by means of self-regulating mechanisms

structure of the plasma membrane: ___________ bilayer with embedded ________

hydrophilic proteins have polar heads

• true

• false

hydrophilic: water ______

hydrophobic proteins have polar tales

• true

• false

hydrophobic: water _______

cholesterol controls excess

• fluidity

• proteins

• hydrophilics