The pH of living tissue is highly variable, depending on the specific tissue type and its physiological state. However, most tissues maintain a relatively narrow pH range, typically between 6.5 and 7.5, slightly acidic to slightly alkaline.

Here's a breakdown:

* Blood: The pH of blood is tightly regulated around 7.35 to 7.45, which is slightly alkaline. This is crucial for proper function of enzymes and proteins in the blood.

* Muscle: The pH of muscle tissue can fluctuate depending on activity levels. During intense exercise, muscle tissue can become more acidic due to the build-up of lactic acid. However, resting muscle tissue typically has a pH around 7.0.

* Skin: The surface of the skin is slightly acidic, with a pH around 5.5, which helps protect against bacteria and fungi.

* Stomach: The stomach is highly acidic, with a pH ranging from 1.5 to 3.5, thanks to the production of hydrochloric acid. This acidity is essential for digestion.

* Intestines: The pH of the small intestine is generally slightly alkaline, around 7.0 to 8.0, while the large intestine is slightly acidic, around 6.0 to 7.0.

It's important to note that the pH of specific cells within a tissue can also vary. For example, the pH of lysosomes within a cell is highly acidic, which is necessary for their function in breaking down cellular waste.

Overall, the pH of living tissue is carefully regulated to ensure optimal functioning of cells and tissues. Any significant deviation from the normal pH range can have serious consequences for health.