Where are receptors loacted ?

Explanation

### Step-by-Step Solution:

1. **Understanding Receptors**: Receptors are specialized proteins that bind to specific molecules (ligands) such as hormones, neurotransmitters, or drugs, initiating a cellular response.

2. **Location of Receptors**: Receptors are primarily located in the cell membrane. They can be embedded within the lipid bilayer of the membrane or can be found on the surface of the membrane.

3. **Structure of the Cell Membrane**: The cell membrane consists of a phospholipid bilayer with embedded proteins, including receptor proteins. The outer surface of the membrane faces the external environment, while the inner surface faces the cytoplasm of the cell.

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