💡 Human Body

Explanation: The stapes (stirrup bone) in the middle ear is the smallest bone in the human body, measuring about 3mm. It transmits sound vibrations from the eardrum to the inner ear.

Explanation: A normal resting heart rate for adults is 60-100 beats per minute. Athletes may have lower resting heart rates (40-60 bpm) due to greater cardiovascular efficiency.

Explanation: The average normal human body temperature is 37°C (98.6°F). A fever is generally defined as a temperature above 38°C (100.4°F).

Explanation: Vitamin D (the sunshine vitamin) is synthesized in the skin when ultraviolet B (UVB) rays from sunlight strike the skin. It is essential for calcium absorption and bone health.

Explanation: An adult human has 32 permanent teeth, including 4 wisdom teeth (third molars). Without wisdom teeth, the count is 28. Children have 20 primary (milk) teeth.