What do you mean by single- unit smooth muscles?

Explanation

### Step-by-Step Solution:

1. **Definition of Single-Unit Smooth Muscles**: Single-unit smooth muscles, also known as visceral smooth muscles, are a type of smooth muscle found in various organs such as the uterus, gastrointestinal tract, and bladder.

2. **Characteristics**: These muscles are characterized by their ability to contract as a single unit. This means that when one muscle cell contracts, it triggers the contraction of adjacent muscle cells due to their interconnectedness.

3. **Structure**: The muscle cells in single-unit smooth muscles are spindle-shaped. They are connected to each other through structures called cytoplasmic bridges, which facilitate communication and coordinated contraction among the muscle fibers.

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