The level up from DNA is proteins, the molecules that actually do stuff. These are relatively structured:
Primary structure is the amino acid sequence.
Secondary is the structures that from out of the primary sequence:
Helices coil, like DNA except except only a single helix not double. Double and triple helices (see keratin and collagen respectively) are more like winding 2 or 3 single helices around themselves, and
Sheets: two or more strands that bond to each other either parallel or antiparallel.
Then it starts to get interesting. These secondary structures form domains which are the functional subunit of proteins that actually do (or are in the case of non-enzymes) stuff. These are the equivalent of structured programming. E.g. join an antibody variable domain (the bit that stick to stuff) to an enzyme, inject it into the bloodstream and you get expression on the enzyme wherever the antibody happens to bind (e.g. to a cancer cell).
(Tertiary and quaternary structure refer to the complete protein and to proteins that form a functional unit with other proteins respectively.)
The OO analogy is like the OO analogy for HDLs, the protein _is_ an object. OS is whole organism level.
Secondary is the structures that from out of the primary sequence: Helices coil, like DNA except except only a single helix not double. Double and triple helices (see keratin and collagen respectively) are more like winding 2 or 3 single helices around themselves, and Sheets: two or more strands that bond to each other either parallel or antiparallel.
Then it starts to get interesting. These secondary structures form domains which are the functional subunit of proteins that actually do (or are in the case of non-enzymes) stuff. These are the equivalent of structured programming. E.g. join an antibody variable domain (the bit that stick to stuff) to an enzyme, inject it into the bloodstream and you get expression on the enzyme wherever the antibody happens to bind (e.g. to a cancer cell).
(Tertiary and quaternary structure refer to the complete protein and to proteins that form a functional unit with other proteins respectively.)
The OO analogy is like the OO analogy for HDLs, the protein _is_ an object. OS is whole organism level.