FUNCTIONS - ( Fig. 1 ) Hormones, growth factors,...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
FUNCTIONS 1. Compartmentalization Membranes enclose compartments --- plasma membrane encloses entire cell---- nuclear and cytoplasmic membranes enclose various internal cellular spaces in which specialized activities take place. 2. Provides a selectively permeable membrane barrier Movement of molecules either into or out of cell is regulated . Only very small uncharged molecules can readily diffuse i.e. . O2 and CO2 ( Fig. 1 ). 3. Provides for the transportation of solutes The membrane contains the machinery for physically transporting substances from one side of the membrane to another --- even against a concentration gradient ( Fig. 1 ). 4. Ability to respond to external signals Receptors on surface have a particular ligand . When ligand binds to the receptor the signal must be transduced to the nucleus. Signal Transduction
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: ( Fig. 1 ) Hormones, growth factors, neurotransmitters can all serve as ligands. 5. Provides for intercellular and intracellular interactions cell-cell adhesion cell-ECM adhesion linkers add strength and shape to membrane and localize other proteins ( Fig. 1 ). 6. Serves as a site for biochemical activities Organizes cellular activities by the association of multi-enzyme complexes i.e. electron transport chains. 7. Provides for energy transduction Transduction refers to the conversion of one type of energy into a different form of energy. Ex: the energy of sunlight is absorbed by membrane-bound photosynthetic pigments and converted to chemical energy contained in carbohydrates. Conversely- the chemical energy in carbohydrates and fats can be converted to ATP....
View Full Document

This document was uploaded on 11/03/2011 for the course BIOLOGY MCB2010 at Broward College.

Ask a homework question - tutors are online