The right answer is more Chemical bonds.
Lipids are the most energetic macronutrients (as a reminder: 1 g of lipids represents 9 kcal, against 4 kcal for 1 g of carbohydrates or 1 g of proteins). Lipids are the molecules present in the fat of foods. They divide into saturated fatty acids and unsaturated fatty acids. These fatty acids can contain between 4 and 20 carbon molecules while carbohydrates contain between 3 and 6 carbon molecules.
The subunit of proteins is one protein molecule that assembles with more protein molecules to make a protein complex.
Hope this helps! ;)
<em>The answer is endoplasmic reticulum</em>
Molecular biologists are interested in things like the level of gene expression (how much protein or RNA is present at any given time), which molecules are directly touching each other inside the cell, etc. ... Cell biology techniques, on the other hand, want to know what's going on inside intact cells.
( Try to see which one sounds best after reading this)
