Earth 113 Ch 24 Review Clickers

The statement is true because the theory of evolution states that all living organisms on Earth share a common ancestor. This means that over time, through a process of natural selection and genetic variation, different species have evolved and branched out from a single common ancestor. The evidence for this theory is supported by fossil records, genetic similarities between species, and the observation of natural selection in action.

Life on Earth is believed to have originated between 3 and 4 billion years ago. This estimate is based on scientific evidence such as the presence of fossilized microorganisms and the age of rocks containing these fossils. The earliest known life forms on Earth were simple, single-celled organisms that existed in ancient oceans. While the exact timeline and specific details of how life began are still not fully understood, the consensus among scientists is that life emerged on Earth billions of years ago.

The correct answer is 5 billion years. This estimate is based on scientific evidence and the age of the oldest rocks on Earth. Through radiometric dating of these rocks and meteorites, scientists have determined that the Earth formed around 4.5 billion years ago. This age is also consistent with the age of the solar system, as determined by dating the oldest meteorites.

The discovery of DNA showed the mechanism of mutation, which explains why organisms change over time. This supports the theory of evolution proposed by Darwin, as it provides a scientific explanation for how species evolve and adapt to their environments. Darwin's theory of natural selection did not have a clear understanding of the underlying mechanism of genetic variation, which DNA discovery helped to elucidate.

The given answer suggests that the discovery of strange, living microbes and larger organisms on Europa is likely because there is evidence for an ocean underneath the icy surface of Europa. Water is a good place to look for life, and the presence of biosignatures detected by the Voyager 2 spacecraft supports the possibility of finding life on Europa.

The age of the Earth can be determined through radiometric dating of the oldest Earth rocks, Moon rocks, and meteorites. Radiometric dating is a technique that uses the decay of radioactive isotopes to estimate the age of rocks and minerals. By measuring the ratio of parent isotopes to daughter isotopes, scientists can calculate the amount of time that has passed since the rock or mineral formed. By using multiple sources such as Earth rocks, Moon rocks, and meteorites, scientists can cross-reference and validate their findings, providing a more accurate estimation of the Earth's age.

The correct answer is by dating rocks in which the fossils are found (determined from layering and radiometric dating of the rocks). This method allows scientists to determine the age of the rocks and fossils by analyzing the different layers of rock and using radiometric dating techniques. By studying the composition and age of these rocks, scientists can estimate when the first life arose on Earth. Counting tree rings and radiometric dating of fossils are not directly related to determining the age of the first life on Earth.

The correct answer is "all of the above". This is because the fossil record provides evidence of organisms with similar appearances that change over time, indicating a common ancestor. Additionally, DNA analysis has shown remarkable similarities among all life forms, further supporting the idea of a common ancestor. Furthermore, DNA is more similar among closely related forms, which again suggests a shared ancestry.

Purely chemical burning, such as burning coal, cannot release enough energy to achieve speeds close to the speed of light. The energy released from chemical reactions is limited compared to the immense energy required to reach such high speeds. Therefore, the idea of a rocket powered by coal achieving half the speed of light is not feasible and falls into the realm of fantasy.

The correct answer is that it is a fantasy because Voyager 2 will take tens of thousands of years to reach the distance of even the nearest stars. This explanation is based on the fact that Voyager 2 is currently traveling at a speed of about 15 kilometers per second, which is not sufficient to reach the nearest stars within a reasonable timeframe. Therefore, it is highly unlikely that Voyager 2 could have crash-landed on a planet around a nearby star in the year 2750.

It is unlikely that life could have arisen before about 3-4 billion years because Earth was too hot, as the high temperatures would have made it difficult for life to exist. Additionally, Earth was being bombarded by planetesimals that formed the solar system, which would have disrupted any potential life forms. Furthermore, Earth may not have had much water yet, and water is essential for the development and sustenance of life. All of these factors combined make it unlikely that life could have emerged before 3-4 billion years ago.

The correct answer is "all of the above". This is because in order to understand the evolution of life from simple to more complex, we need to study the mechanism of evolution through DNA and mutation, just like we study the mechanism of star evolution through fusion and gravity. Additionally, we look for clues of various stages of evolution through fossils, similar to how we study the different stages of star evolution through red giants and white dwarfs. Finally, the scientific method allows us to make predictions about what should be found in the evolutionary process and then go look for evidence to support those predictions. Therefore, all of these approaches are used to understand the evolution of life from simple to complex.

The given correct answer is "all of the above". This suggests that there could be life on Mars because there is evidence of liquid water today and in the past, Mars has a climate that was likely warmer in the past, and it has an atmosphere. These factors are important for the existence of life as we know it, making it plausible that life could exist on Mars.

The answer "all of the above" is correct because the passage states that we don't know exactly how life arose on Earth, but we have some clues, such as DNA studies suggesting that the first life may have lived in hot water near volcanic vents. It also mentions that this topic is an important subject of scientific study. Therefore, all of the statements mentioned in the options are supported by the given information.

Scientists can determine the age of different rocks on Earth by examining the layering of rocks and studying the rate of radioactive decay. The layering of rocks is similar in many places on Earth, allowing scientists to assess the ages of rocks by comparing different layers. Additionally, some elements in rocks gradually change into other elements due to radioactivity, and this rate of change can be studied in the lab. By applying this rate to rocks, scientists can determine their age. Therefore, both options A and C are correct.

Charles Darwin proposed the theory of evolution based on evidence from fossils and from the observation that organisms varied from generation to generation. Although DNA had not been discovered during Darwin's time, his theory still provided an explanation for why organisms varied, even without knowledge of the specific mechanism behind it. Therefore, the correct answer is B and C.

Mutation causes antibiotics to gradually lose their effectiveness against certain infections. This is because bacteria can develop resistance to antibiotics through genetic mutations. Over time, these mutations can lead to the emergence of antibiotic-resistant strains of bacteria, making it harder to treat infections effectively. This is a significant issue in modern healthcare, as it limits the effectiveness of many commonly used antibiotics and poses a threat to public health.