Question

the smooth er is especially abundant in cells that synthesize extensive amounts of
toxins like hydrogen peroxide
proteins like hemoglobin
enzymes like amylase
lipids like hormones and cholesterol

Explanation:

1. Recall the function of smooth endoplasmic reticulum (smooth ER): Smooth ER is mainly involved in lipid synthesis (including steroid hormones, cholesterol) and detoxification, but the key here is its role in lipid synthesis.
2. Analyze each option:

• "Toxins like Hydrogen peroxide": Hydrogen peroxide is detoxified by peroxisomes, not a main product of smooth ER synthesis.
• "Proteins like hemoglobin": Protein synthesis is the role of ribosomes and rough ER (which has ribosomes).
• "Enzymes like amylase": Enzymes (proteins) are synthesized by ribosomes/rough ER.
• "Lipids like hormones and cholesterol": Smooth ER is abundant in cells that synthesize lipids (like steroid hormones, cholesterol), so this matches the function of smooth ER.

Answer:

D. Lipids like hormones and cholesterol (assuming the options are labeled A - D with D being "Lipids like hormones and cholesterol")