Which macronutrient is the body's primary and most efficient source of quick energy?

Which enzyme present in saliva begins the digestion of starch in the mouth?

Which vitamin deficiency commonly causes night blindness in humans?

Which cell organelle is often referred to as the powerhouse of the cell due to its role in energy production?

Which chamber of the heart receives deoxygenated blood from the body before sending it to the lungs?

Which common everyday substance is classified as a strong acid frequently used in car batteries?

Which natural process explains how mountains gradually wear down over long periods of time?

Which fluid lubricates joints and reduces friction between bones during movement?

Which astronomical event marks the day with the longest period of daylight in the Northern Hemisphere?

Which gas makes up approximately 21 percent of Earth's atmosphere and is essential for respiration?

Which stomach enzyme is primarily responsible for breaking down proteins into smaller peptides?