Video Transcript
Which of the following characteristics is not likely to be essential for maintaining the continuity of life on Earth? (A) A suitable atmospheric pressure, (B) a suitable temperature, (C) the atmosphere, (D) the hydrosphere, or (E) the shape of the continents.
For this question, we need to consider life on Earth. So, we must also consider the atmosphere and the hydrosphere. The atmosphere is defined as the layer of gases that surrounds the solid Earth. The atmosphere contains gases, such as carbon dioxide and oxygen. Carbon dioxide is needed for photosynthesis in plants, and oxygen is needed for respiration in animals. Therefore, the atmosphere is essential for maintaining the continuity of life on Earth. And answer choice (C), the atmosphere, is not the answer.
It’s not just the types of gases present in the atmosphere that we should consider, but also the pressure of those gases. Life on Earth has developed and adapted according to the atmospheric pressure. A drastic change in pressure can endanger life. For example, people can become sick from a lack of oxygen when climbing very high mountains. Therefore, answer choice (A), a suitable atmospheric pressure, is not the answer.
The hydrosphere is the component of Earth that includes all the water that exists on the planet’s surface, in the ground, and in the air. Water is essential for life on Earth, as it is consumed by animals and plants, and is the main component of many habitats for a vast number of animals. Therefore, answer choice (D), the hydrosphere, is not the answer.
Temperature is another important consideration for life on Earth. Temperature directly impacts life as a dramatic change in temperature can cause the health of organisms to deteriorate and can even cause death. Change in temperature can also impact weather patterns, for example, which also impacts life. Therefore, answer choice (B), a suitable temperature, is not the answer.
The only remaining answer choice is the shape of the continents. The shape of the continents is constantly undergoing minor changes, and it has little impact on life. Therefore, the characteristic which is not likely to be essential for maintaining the continuity of life is (E), the shape of the continents.
