Proteins serve a variety of functions in living organisms. which of the following protein-containing substances plays a role in the regulation of cell functions?

Answer

They are "hormones" that are protein-containing substances that play a role in the regulation of cell functions, although it should be noted that this is not their only function

Explanation

Protein is a class of nitrogenous compounds which contains large molecules which compose amino acids. Protein can be sourced from different varieties of food some of them being eggs, beans.seafood and many others.

Proteins can perform many different functions in living cells. One major function, acting as a catalyst for chemical reactions, They have "hormones" that are protein-containing substances that play a role in the regulation of cell. They are also required for regulation of body tissues and organs among other things they perform.

the graph shows the spread of railways in the 1800s.

based on the graph, the conclusion that can be drawn about germany is answer d)   by 1880, germany had more rail lines than great britain and russia.