<span>The key points about cell theory are as follows:
1. All living organisms are made up of cells; the organisms may be unicellular or multi cellular.
2. The cell is the basic unit of life.
3. New cells are derived from pre-existing cells.
4. All cells maintain homeostasis.
Some new facts have been added to these basic facts; the new facts added include the following:
(A). Energy flow occur withing all living cells.
(B). Hereditary information derived from DNA is passed from cell to cell.
(C). All living cells are made up of the same basic chemical compositions.</span>
A housekeeper I think , that's the answer
Protein
Proteins are the most versatile
macromolecules in living systems and they play important roles in essentially
all biological processes. Protein makes up the capsid of a virus. The infective
extracellular form of a virus known as a virion contains at
least one unique protein synthesized by specific genes in the nucleic acid of
that virus. In almost all viruses, at least one of these proteins forms a shell
(called a capsid) around the nucleic acid. Certain viruses also have other
proteins internal to the capsid. Some of these proteins act as enzymes during
the synthesis of viral nucleic acids.
