Smooth endoplasmic reticulum is abundant in liver cells, cells in brain and the cells in the muscles of limbs. What are the functions performed by it in the respective cells?

Explanation

### Step-by-Step Solution:

1. **Understanding Smooth Endoplasmic Reticulum (SER)**:
- The smooth endoplasmic reticulum (SER) is a type of endoplasmic reticulum that lacks ribosomes on its surface, distinguishing it from rough endoplasmic reticulum (RER). It plays various roles in different types of cells.

2. **Functions of SER in Liver Cells**:
- In liver cells, the SER is primarily involved in **detoxification**. This means it helps to process and eliminate toxins, drugs, and metabolic waste products from the body. The liver is a crucial organ for detoxifying harmful substances, and the SER plays a vital role in this process.

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