Membrane fluidityIn biology, membrane fluidity refers to the viscosity of the lipid bilayer of a cell membrane or a synthetic lipid membrane. Lipid packing can influence the fluidity of the membrane. Viscosity of the membrane can affect the rotation and diffusion of proteins and other bio-molecules within the membrane, there-by affecting the functions of these things. Membrane fluidity is affected by fatty acids. More specifically, whether the fatty acids are saturated or unsaturated has an effect on membrane fluidity.
Physiologie cellulaireCell physiology is the biological study of the activities that take place in a cell to keep it alive. The term physiology refers to normal functions in a living organism. Animal cells, plant cells and microorganism cells show similarities in their functions even though they vary in structure. There are two types of cells: prokaryotes and eukaryotes. Prokaryotes were the first of the two to develop and do not have a self-contained nucleus. Their mechanisms are simpler than later-evolved eukaryotes, which contain a nucleus that envelops the cell's DNA and some organelles.
Biopolymèrevignette|De gauche à droite, les structures de l'ADN A, B et Z. La structure d'une molécule d'ADN dépend de son environnement. Dans les environnements aqueux, y compris la majorité de l'ADN dans une cellule, l'ADN-B est la structure la plus courante. La structure A-ADN domine dans les échantillons déshydratés et est similaire à l'ARN double brin et aux hybrides ADN/ARN. L'ADN-Z est une structure plus rare que l'on trouve dans l'ADN lié à certaines protéines.
