1. which of the following statements about proteins is incorrect?

(a) all proteins are made up of some combination of 20 essential amino acids.
(b) like nucleic acids, polypeptides have polarity.
(c) a single polypeptide has primary, secondary and tertiary structures.
(d) α-helix and β-pleated sheets do not require specific sequence of amino acids to form.
(e) some proteins contain more than one polypeptide chain.

Option A.

Explanation: The correct answer to the question is option A, because not all proteins are made up of some combination of 20 essential amino acids.

a neutral ph of 7 and normal organism temperature is needed for a certain enzyme to be effective.  

what would happen to the enzyme if the ph and/or temperature fluctuate greatly from the norm?  

a.the enzyme’s hydrogen bonds will break.  

b.the activation energy will increase.  

c.more product will be formed.

d.the ideal temperature and ph for the enzyme function will decrease.