Human Health And Disease

Step 1: Understanding the Concept:
The endocrine system is a system of glands that produce hormones. An endocrine disorder is a medical condition that occurs when a gland in the endocrine system produces too much or too little of a hormone.

Step 2: Detailed Explanation:
- Diabetes (specifically Diabetes Mellitus) is a classic endocrine disorder. It is caused by either the pancreas not producing enough of the hormone insulin or the body not effectively using the insulin it produces.
- Asthma is a chronic respiratory disease.
- Malaria is an infectious disease caused by a parasite.
- Stomach ache is a symptom, not a disorder itself.

Step 3: Final Answer:
Diabetes is a disorder related to the hormone insulin and the pancreas, making it an endocrine disorder.

Step 1: Understanding the Concept:
The question asks for the earliest and most common indicator of pregnancy.

Step 2: Detailed Explanation:
- The Closure of the menstrual cycle, commonly known as a missed period, is the hallmark and most reliable early sign of pregnancy. This happens because the hormone progesterone, produced after conception, prevents the uterine lining from shedding.
- Morning sickness (nausea and vomiting) and Frequent urination are also common early symptoms, but they typically begin a few weeks after the missed period.
- Therefore, a missed period is considered the first sign.

Step 3: Final Answer:
The first and most dependable symptom of pregnancy is the closure of the menstrual cycle (a missed period).