Lecture 3 Flashcards
movement of biochemicals and other atomic or molecular substances across membranes; does not require input of chemical energy
passive transport
process of spontaneous passive transport of molecules or ions across a biological membrane via specific transmembrane integral proteins
facilitated diffusion
movement of molecules across membranes by mechanisms that use some form of energy expenditure to accomplish movement
active transport
spontaneous net movement of solvent molecules through a semi-permeable membrane into a region of higher solute concentration in the direction that tends to equalize the solute concentrations on the two sides
osmosis
family of biological membrane proteins which allow the passive movement of ions, water, or other solutes to passively pass through the membrane down their electrochemical gradient
channel
integral membrane protein involved in the movement of ions, small molecules, or macromolecules, such as another protein across a biological membrane; assist by facilitated diffusion or active transport; mechanisms are known as carrier mediated transport
transporter
cell-cell and cell-matrix interactions mediated through extracellular proteins that hold cells together to form tissues
cell junctions
4 major types of cell junctions
anchoring junctions, occluding junctions, channel forming junctions, and signal relaying junctions
gap junctions are formed by _____
6 connexins
What ion makes cadherin chains more rigid?
Ca2+
______ and ______ (cell junction) create a barrier to the movement of molecules extracellularly between cells
tight and adherens junctions
cell junctions formed between cells to allow molecules to move back and forth (size limiting)
gap junctions
cell junctions that maintain the integrity and organization of cell
anchoring junctions
coupled transport where molecules are cotransported in opposite directions
antiport
coupled transport where molecules are cotransported in same direction
symport
