Diaphragm...is the muscle that helps in respiration.....there are also some other but....you said flat so diaphragm !
<span>The correct answers are that it lacks cells, DNA, and cannot maintain homeostasis. It doesn't have any organic matter and homeostasis is impossible because it would turn off eventually. It doens't have DNA and it doesn't reproduce. It's just plasma and it is not a living being, it just moves because of the chemical reactions that occur. </span>
The best answer is B - Proteins.
Proteins make up enzymes, or to put it another way enzymes are made up of protein. It is enzymes that speed up the chemical reactions. Enzymes are organic catalysts, substances that speed up a (biochemical) reaction but do not take part in the reaction and remain unchanged at the end of the reaction.
In man, there are many enzymes. The majority of these are found in the digestive system where they greatly aid the process of food breakdown from complex molecules to simple molecules. Examples include salivary amylase found in saliva, which begins the gradual breaking down of starch into glucose right from the moment food is placed in the mouth and mixed with saliva. Pepsin in the stomach breaks down protein.
Chemosynthesis is the biological conversion of one or more carbon- containing molecules.