Apart from sodium pumps, state one other effector that would be involved in the increase in water volume in the body.

One other effector that would be involved in the increase in water volume in the body is the antidiuretic hormone (ADH), also known as vasopressin.

Here are the steps of how it works:

1. When the body is dehydrated, the hypothalamus in the brain detects this and signals the pituitary gland.

2. The pituitary gland then releases ADH into the bloodstream.

3. ADH travels in the blood to the kidneys.

4. In the kidneys, ADH makes the collecting ducts more permeable to water.

5. This allows more water to be reabsorbed back into the blood from the kidney tubules, which leads to less water in urine.

6. As a result, the volume of water in the body increases.

So, ADH plays a crucial role in regulating the water volume in the body.