Diabetes insipidus results from deficiency of ______while diabetes mellitus is caused by a deficiency of __________

Answer

To answer the question regarding the deficiencies that cause diabetes insipidus and diabetes mellitus, we can break it down as follows:

### Step-by-Step Solution:

1. **Understanding Diabetes Insipidus**:
- Diabetes insipidus is a condition characterized by excessive urination and thirst. It occurs when the kidneys cannot conserve water, leading to increased urine output.
- This condition is primarily caused by a deficiency in a specific hormone that regulates water reabsorption in the kidneys.

2. **Identifying the Hormone**:
- The hormone responsible for water reabsorption is secreted by the hypothalamus and is known as **vasopressin** or **antidiuretic hormone (ADH)**.
- A deficiency in vasopressin leads to the kidneys' inability to reabsorb water, resulting in dehydration and increased thirst.

3. **Understanding Diabetes Mellitus**:
- Diabetes mellitus is a metabolic disorder characterized by high blood sugar levels over a prolonged period. It is commonly referred to simply as diabetes.
- This condition arises when the pancreas does not produce enough insulin, which is crucial for regulating blood glucose levels.

4. **Identifying the Hormone**:
- The hormone that is deficient in diabetes mellitus is **insulin**. Insulin helps cells absorb glucose from the bloodstream, and without sufficient insulin, glucose accumulates in the blood, leading to high blood sugar levels.

5. **Final Answer**:
- Therefore, diabetes insipidus results from the deficiency of **vasopressin (ADH)**, while diabetes mellitus is caused by a deficiency of **insulin**.

### Summary:
- Diabetes insipidus: deficiency of **vasopressin (ADH)**
- Diabetes mellitus: deficiency of **insulin**