Final answer:
Excessive lipid accumulation in a cell could indicate a malfunction of A) the Smooth ER, which synthesizes phospholipids and steroid hormones. C) Nucleoid and D) Nucleolus are not directly involved in lipid synthesis.
Step-by-step explanation:
If a cell is building up a high amount of lipids, the organelles that could be malfunctioning are A) Smooth ER (Smooth Endoplasmic Reticulum) or B) Rough ER (Rough Endoplasmic Reticulum). C) Nucleoid and D) Nucleolus are not directly related to lipid synthesis. The Smooth ER is particularly important in lipid metabolism, including the synthesis of phospholipids and steroid hormones, which is why its malfunction could lead to a buildup of lipids.
For example, if the organelle referred to in question 16, which has the greatest concentration of smooth ER, were malfunctioning, this could lead to an overaccumulation of lipids. This organelle tends to be a cell that makes steroid hormones, given its extensive smooth ER that specializes in lipid synthesis. Lastly, a malfunctioning nucleolus, referenced in a separate question, would mainly affect ribosomes and protein synthesis, not the buildup of lipids.