Amutation of lys to phe in a protein causes the protein no longer bind it's substrate. the substrate contains several functional groups important for binding to the protein. the mutation of the protein would likely disrupt the binding to which type of functional group?

It would disrupt binding to negatively charged functional groups.

Explanation:

The lysine side chain contains an amino group (-NH3) that is usually protonated under physiolgoical pH (-NH4+), making it positively charged and basic. This enables it to interact with negatively charged functional groups (e.g. deprotonated acids, -COO-). Phenylalanine contains an aromatic ring but no charged functional groups in its side chain. Therefore, a mutation from Lys to Phe would prevent interaction with negatively charged functional groups.

what statement best describes the difference between the sympathetic and parasympathetic nervous systems?

the sympathetic nervous system prepares the body for intense physical activity and is often referred to as the fight-or-flight response. the parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions.