Hippos spend most of their time in rivers, but they come out of the water to eat grass. Right now, it’s the middle of the night. The sun is not shining, and the hippos are not eating. What is happening to the carbon in the air around the hippos and the grass nearby
The Correct Answer and Explanation is:
Correct Answer:
At night, plants like grass stop photosynthesizing and instead respire, releasing carbon dioxide into the air. Hippos, being animals, continue to respire and also release carbon dioxide. Therefore, the amount of carbon dioxide in the air around the hippos and grass is increasing.
300-Word Explanation:
During the night, photosynthesis ceases in plants due to the absence of sunlight. Photosynthesis requires light energy to convert carbon dioxide and water into glucose and oxygen. In the dark, this process cannot occur because the energy source—sunlight—is missing. As a result, grass and other plants shift to a different metabolic process called respiration.
Cellular respiration in plants involves breaking down stored sugars to produce energy for growth and maintenance. This process consumes oxygen and releases carbon dioxide into the surrounding air. Therefore, instead of removing carbon dioxide from the air, the grass now contributes to its increase.
Meanwhile, hippos continue to perform cellular respiration throughout the day and night. Their bodies convert nutrients into usable energy by using oxygen and releasing carbon dioxide as a byproduct. Since the hippos are not feeding at night, their physical activity may be minimal, but basic life functions such as breathing and body temperature regulation still require energy, which leads to the continuous release of carbon dioxide.
Without the photosynthetic activity of plants to absorb carbon dioxide, the surrounding environment experiences a net increase in carbon dioxide concentration. This process continues until sunrise, when the light-dependent reactions of photosynthesis resume and plants begin to absorb carbon dioxide again.
This cycle of daytime carbon absorption and nighttime carbon release plays a vital role in maintaining the balance of atmospheric carbon. It highlights how both animals and plants contribute to the carbon cycle, with roles that shift based on time of day and environmental conditions.
