What type of lipid structure requires a phosphate group, and what is the most common use of this lipid structure in a cell?

Which of the following functions is not compromised due to low levels of lipids?

Which of the following sphingolipids is also a phospholipid?

Which type of lipid is both an important component of cell membranes and the precursor of steroid hormones?

After a serum test, it is observed that a patient has very low levels of a substance. Nuclear magnetic resonance (NMR) and infrared (IR) analysis reveal that the substance has a three-carbon backbone that has two, long hydrocarbon chains and a phosphate group attached. Which of the following structures is most likely compromised in this patient?