Answer:
Probably the Electrical energy has to be stored in batteries for several days
The answer that fits the blank provided above is STEROIDS. Steroids are fat-soluble signal molecules. This is one of the derivative compounds of cholesterol along with Vitamin D and bile salts. All steroid hormones are considered as a derivative of cholesterol. The answer for this would be option D.
Endoplasmic Reticulum is a long piece of membrane inside of the cytoplasm in a Eukaryotic cell. It connects to the Nuclear Membrane as well. It has numerous ribosomes attached as it helps with protein and lipid synthesis. It has both smooth and rough forms, each which do different things inside the cell.
