The inner lining of the urinary bladder is composed of transitional epithelium.

Explanation:
The inner lining of the urinary bladder is composed of a specialized type of epithelial tissue called transitional epithelium. This type of epithelium is found in organs that need to stretch and accommodate changes in volume, such as the urinary bladder.

Transitional epithelium:
- Transitional epithelium is a stratified epithelium that is capable of stretching and recoiling without tearing.
- It consists of multiple layers of cells that change shape depending on the degree of distension of the bladder.
- When the bladder is empty, the cells appear cuboidal or columnar, and when the bladder is full, the cells become flattened and squamous.
- This ability to change shape allows the bladder to expand and contract, accommodating varying volumes of urine.

Functions of transitional epithelium:
- Protection: The multiple layers of cells in transitional epithelium provide a protective barrier against the toxic substances present in urine.
- Stretching: Transitional epithelium allows the bladder to stretch and accommodate changes in urine volume. It can expand significantly without tearing or rupturing.
- Impermeability: The cells of transitional epithelium are tightly packed and have specialized junctions that prevent urine from leaking into the surrounding tissues.

Other layers of the urinary bladder:
- The transitional epithelium forms the innermost layer of the urinary bladder.
- Outside the transitional epithelium, there is a layer of connective tissue called the lamina propria. It contains blood vessels, nerves, and immune cells.
- The next layer is the muscular layer, consisting of smooth muscle fibers arranged in three layers: inner longitudinal, middle circular, and outer longitudinal.
- The outermost layer is the serosa or adventitia, depending on the location of the bladder in the body.

In conclusion, the inner lining of the urinary bladder is composed of transitional epithelium, which allows the bladder to stretch and accommodate changes in urine volume. This specialized epithelium plays a crucial role in maintaining the integrity and function of the bladder.