1. radioactive decay occurs when atoms
A- lose mass
B- join with atoms of another element
C- break down to form atoms of another element
D- are exposed to chemical weathering
2. if you want to consult the geologic time scale for when the first vertebrates evolved, where would you look?
A- in the section for the Ordovician period of the paleozoic era.
B- in the section for the quaternary period of the cenozoic era.
C- in the section for the triassic period of the mesozoic era.
D- in the section for precambrian time.
3. Earths atmosphere, oceans, and continents began to form during the first several hundred million years of.
A- precambrian time
B- the paleozoic era.
C- the mesozoic era
D- the cenozoic era
4. During the devonian period, animals that could live on land began to evolve. these animals still spent part of there lives in the water. what where these animals called?
A- trilobites.
B- reptiles.
C- amphibians.
D- dinosaur.
5. which of the following events occurred during the mesozoic era?
A- dinosaurs became common on lane.
B- whales and dolphins evolved in the ocean.
C- reptiles evolved on land.
D- the supercontinent Pangaea formed.
6. which of the following vertebrates had the chance to become abundant after the dinosaurs became extinct?
A- woolly mammoths.
B- amphibians.
C- mammals.
D- reptiles.
7. which of the following organisms is not extinct?
A- the dodo bird.
B- the saber-tooth tiger.
C- the saltwater crocodile.
D- the Carolina parakeet.
8. During which section of the geologic time scale did the first modern humans evolved?
A- during the paleogene period of the cenozoic era.
B- during the quaternary period of the Cenozoic era.
C- during the cretaceous period of the mesozoic era.
D- during precambrian time.
9. if a geologist found two fossil of different species buried next to each other in a rock layer, he or she might hypothesize that the two organisms may have been alive during the same time period?
-True
-False
10. a species might become extinct when a disastrous event, such as a meteorite impact, occurs.
-True
-False
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1. The correct answer is C - radioactive decay occurs when atoms break down to form atoms of another element. Radioactive decay is a natural process where unstable atoms lose energy by emitting radiation in the form of particles or electromagnetic waves.
2. To consult the geologic time scale for when the first vertebrates evolved, you would look in the section for Option A - the Ordovician period of the Paleozoic era. The geologic time scale is a chronological representation of Earth's history divided into various periods, epochs, and eras based on geological and fossil evidence.
3. The correct answer is A - precambrian time. Earth's atmosphere, oceans, and continents began to form during the first several hundred million years of Earth's history, which is part of the precambrian time. This period spans from the formation of Earth, around 4.6 billion years ago, to the beginning of the Cambrian period, around 541 million years ago.
4. The correct answer is C - amphibians. During the Devonian period, animals that could live on land, but still spent part of their lives in the water, began to evolve. These animals were called amphibians and represented an important step in the transition from aquatic to terrestrial life.
5. The correct answer is D - the supercontinent Pangaea formed. The Mesozoic era, also known as the "Age of Dinosaurs," which spanned from approximately 252 million years ago to 66 million years ago, witnessed several important events. These include the formation of the supercontinent Pangaea, the rise of dinosaurs, and the eventual mass extinction event that led to the end of the era.
6. The correct answer is C - mammals. After the dinosaurs became extinct, mammals had the opportunity to become abundant. This occurred during the Cenozoic era, which followed the Mesozoic era and spans from approximately 66 million years ago to the present.
7. The correct answer is C - the saltwater crocodile. The dodo bird, saber-tooth tiger, and Carolina parakeet are all extinct, while the saltwater crocodile is still alive today. Extinction occurs when a species no longer has any living members.
8. The correct answer is B - during the Quaternary period of the Cenozoic era. The first modern humans, Homo sapiens, evolved during the Quaternary period, which began approximately 2.6 million years ago and continues to the present day. This period also witnessed the development of human civilization.
9. True. If a geologist found two fossils of different species buried next to each other in a rock layer, it is possible to hypothesize that the two organisms may have been alive during the same time period. This observation suggests that the rock layer represents a specific time interval when both species coexisted.
10. True. A species might become extinct when a disastrous event, such as a meteorite impact, occurs. Catastrophic events can have severe impacts on ecosystems and lead to the extinction of species. For example, the extinction of dinosaurs is widely believed to be caused by an asteroid impact approximately 66 million years ago.