Answer:
(b) Both have the same number of valence electrons.
Step-by-step explanation:
We find the most striking chemical similarities between two Main Group elements when they are in the same Group of the Periodic Table.
Elements in the same Group have the same number of valence electrons.
(a) is <em>wrong</em>, because elements in the same group have <em>different masses</em>.
(c) is <em>wrong,</em> because atoms with the same number of protons belong to the s<em>ame element</em>.
(d) is wrong, because elements in the same Group must be in .
<em>different Periods.</em>
Answer:
The concentration of protons affects an enzyme's folded structure and reactivity.
Explanation:
Enzymes act within narrow pH limits (optimal reaction pH). Since most enzymes have a protein structure, the variation in pH or temperature affects their enzymatic activity.
To catalyze a reaction, an enzyme binds to one or more reagent molecules. These molecules are the substrates of the enzyme.
In some reactions, a substrate breaks into several products. In others, two substrates join together to create a larger molecule or to exchange parts. In fact, for any biological reaction that can occur to you, there is probably an enzyme to accelerate it.
The part of the enzyme where the substrate binds is called the active site.
The amino acid residues of the active site often have acidic or basic properties that are important for catalysis. Changes in pH can affect these residues and make binding with the substrate difficult.
