A secondary structure called an alpl-ra- is shaped like a coil with hydrogen bonds that form along a single segurent of a peptide.

im pretty sure its b

answer: cellular respiration takes in food and uses it to create atp, a chemical which the cell uses for energy. usually, this process uses oxygen, and is called aerobic respiration. it has four stages known as glycolysis, link reaction, the krebs cycle, and the electron transport chain.