Quiz on Respiration in Organisms

Respiration is the biological process through which living organisms release energy from the food they consume. This energy is essential for growth, repair, and carrying out all life activities. Respiration occurs in every cell and can be of two types — aerobic (in the presence of oxygen) and anaerobic (without oxygen). In aerobic respiration, glucose combines with oxygen to produce carbon dioxide, water, and energy. In anaerobic respiration, less energy is produced, and by-products like lactic acid or alcohol are formed. In humans, respiration involves breathing — inhaling oxygen and exhaling carbon dioxide — but it also includes cellular respiration that happens in mitochondria. Plants also respire, taking in oxygen and giving out carbon dioxide continuously, though photosynthesis occurs only in daylight.