Proteins and Enzymes

ID #2114

Can you please clarify the biological meaning of the word "spontaneous?" Why did Prof. Mehrtens give two definitions of the word in lecture?


Prof. Mehrtens gave two different definitions for the word "spontaneous" because the biological meaning of the term is different than the definition that you would find in the dictionary. The typical definition of spontaneous is that it happens automatically. If biological reactions could happen automatically, then cells would explode because reactions would not be regulated and would be occurring nonstop. All of the heat being released from catabolic reactions would kill cells, and this would not be the most advantageous circumstance for a cell. Instead, a spontaneous reaction in a cell releases energy, but does not necessarily happen automatically. This is how the two definitions differ. All reactions need to be regulated at least somewhat so that they occur when the cell needs them to. A means of controlling catabolic reactions is by having an energy of activation (Ea) that needs to be overcome for a reaction to happen.

Print this record Print this record
Send to a friend Send to a friend
Show this as PDF file Show this as PDF file
Export as XML-File Export as XML-File