Medical Biochemistry, a hierarchy
This post has the intention to help medical students to learn medical Biochemistry in an organized and reasonably planned way. It may provide an interesting introduction trial that is largely personal. Learners of other scientific branches may be also interested by this kind of presentation.
1 predetermination, projection
Projection is used to denote that the characteristics and phenomena exhibited by a single cell may be also noticed in some way in the whole organism. Example: the cell perceives and the organism also perceives.
2 prerequisites, integration and responsiveness
Integration means that the many different compartments and processes in the cell work in a harmony. The cell responds to both external and internal signals, i.e. responsiveness.
3 processes, order, special function and reproduction
Order is the hallmark for any living system and is the utmost goal for every vital process to keep a dynamic steady state. A cell has almost always a special function, e.g. formation of urea by a liver cell (hepatocyte). Cell division is the counterpart for reproduction at the whole organism’s level.
4 concepts, structure-function relationship, thermodynamics laws, non-covalent bonding, and activation-driven change
A function is almost always ascribed to a particular structure, i.e. structure-function relationship, e.g. in proteins. The likelihood for a biochemical process or species to occur can be explained by thermodynamics laws. Non-covalent chemical bonding is wonderful means to permit biochemical structures and changes. Many biochemical processes are initiated through investment of energy, i.e. activation-driven change.
5 central metabolic pathways
Glycolysis (cleavage of glucose), HMP (hexose monophosphate) pathway, TCA (tricarboxylic acid) cycle, cellular respiration (electron transport chain) and fatty acid synthesis and degradation may be good examples.
6 phenomena, shuttling, isomerism, centrality, symmetry, cyclicity, and vital mirroring
Shuttling is needed when biological membranes allow only some biochemical species to pass in or out.
Isomerism means certain spatial orientation of atoms or chemical groups in a given chemical species.
Centrality means the assignment to some key molecule to perform a given role, e.g. glutamate in amino acid metabolism.
Symmetry is important biochemical phenomenon, e.g. in the structure of some biochemical species.
Cyclicity is shown in many changes that take the form of a cycle, e.g. TCA cycle.
Vital mirroring is meant to denote certain biochemical changes on the different sides of biological membranes, e.g. food digest in the intestinal lumen and the contents of portal vein blood.