Question

a proteins alpha helices and beta sheets form their shapes at the ____ level of protein structure. first second third fourth part d what happens to the shape and function of a protein if one of the amino acids is replaced with a different type of amino acid? the protein will unravel and become entirely nonfunctional. it depends on the role of the amino acid that is altered. one amino acid might be replaced with no measurable affect on the protein function; replacing another might cause a total loss of function. the protein will remain unchanged; several amino acids would have to be altered to have any effect on protein function. the proteins fourth - level structure will be damaged.

Explanation:

1. For the first question, protein secondary structure is characterized by alpha - helices and beta - sheets formed by hydrogen - bonding between backbone atoms.
2. For the second question, the function of a protein depends on its amino - acid sequence. Changing one amino acid can have varying effects depending on the role of that amino acid in the protein's structure and function. Amino acids contribute differently to protein folding, stability, and active - site formation.

Answer:

First question: B. second
Second question: B. It depends on the role of the amino acid that is altered. One amino acid might be replaced with no measurable effect on the protein function; replacing another might cause a total loss of function.