1.
The idea that geologic changes happen gradually over time.
Correct Answer
B. Uniformitarianism
Explanation
Uniformitarianism is the correct answer because it refers to the concept that geologic changes occur slowly and gradually over time. This idea suggests that the same processes and natural laws that are observed today have been operating throughout Earth's history. It opposes the concept of catastrophism, which suggests that geological changes are primarily caused by sudden and violent events. Paleontology, on the other hand, is the study of fossils and ancient life forms, which is not directly related to the idea of gradual geologic changes.
2.
The idea that younger rocks lie above older rocks.
Correct Answer
C. Superposition
Explanation
Superposition is the correct answer because it refers to the principle that in undisturbed rock layers, the youngest rocks are found on top, while the oldest rocks are found at the bottom. This concept is based on the understanding that sedimentary rocks are deposited in horizontal layers over time, with each new layer forming on top of the previous ones. By observing the order of these rock layers, scientists can determine the relative ages of the rocks and the events that occurred during their formation.
3.
Which of the following is NOT a type of unconformity:
Correct Answer
A. Singular unconformity
Explanation
The term "singular unconformity" is not a recognized type of unconformity in geology. Unconformities are surfaces that represent gaps in the geological record, indicating periods of erosion or non-deposition. The three types of unconformities that are widely accepted and recognized are nonconformity, angular unconformity, and disconformity. Nonconformity occurs when sedimentary rocks overlay igneous or metamorphic rocks, angular unconformity occurs when tilted or folded rocks are overlain by younger, horizontal layers, and disconformity occurs when there is a gap in the sedimentary rock record between parallel layers.
4.
A detailed series of rock layers that contains all the known fossils and rock formations on Earth.
Correct Answer
B. Geologic column
Explanation
The geologic column is a detailed series of rock layers that contains all the known fossils and rock formations on Earth. It is a representation of the Earth's history and provides a chronological sequence of events. By studying the different layers and the fossils found within them, scientists can determine the relative ages of rocks and fossils, allowing them to piece together the history of the Earth and the evolution of life forms. The geologic column is an important tool in relative dating and understanding the Earth's geological history.
5.
Figuring out whether a rock layer is older or younger than the layers around it.
Correct Answer
C. Relative dating
Explanation
Relative dating is the correct answer because it refers to the process of determining the age of a rock layer by comparing it to the layers around it. This method relies on the principle of superposition, which states that in undisturbed rock layers, the oldest layers are found at the bottom while the youngest layers are found at the top. By examining the position of a rock layer in relation to the layers above and below it, scientists can determine whether it is older or younger than the surrounding layers. Absolute dating, on the other hand, provides a specific age in years for a rock layer using various scientific techniques.
6.
This happens when a radioactive isotope breaks down into a new isotope.
Correct Answer
C. Radioactive decay
Explanation
Radioactive decay refers to the process in which a radioactive isotope breaks down or decays into a new isotope. During this decay, the unstable nucleus of the isotope undergoes a spontaneous transformation, releasing radiation in the form of alpha particles, beta particles, or gamma rays. This process is used in radioactive dating to determine the age of rocks, fossils, and other geological materials. By measuring the amount of remaining radioactive isotopes and knowing their half-lives, scientists can calculate the time that has elapsed since the decay began. Therefore, radioactive decay is the best explanation for the given statement.
7.
Isotopes are atoms of an element that have different numbers of:
Correct Answer
D. Neutrons
Explanation
Isotopes are atoms of an element that have different numbers of neutrons. Protons and electrons are always the same in an atom of a particular element, as they determine the element's identity and charge, respectively. Isotopes, on the other hand, have varying numbers of neutrons, which can affect the atom's stability and mass. Therefore, the correct answer is neutrons.
8.
Finding the exact age of an object is called:
Correct Answer
D. Absolute dating
Explanation
Absolute dating is the process of determining the exact age of an object or event in years. It involves various scientific techniques such as radiometric dating, which uses the decay of radioactive isotopes to calculate the age of rocks and fossils. Unlike relative dating, which determines the age of an object in relation to other objects, absolute dating provides a specific numerical age. This method is crucial in understanding the timeline of Earth's history and the evolution of life on the planet.
9.
The time required for half of a sample of a radioactive isotope to break down by radioactive decay to form a daughter isotope.
Correct Answer
B. Half-life
Explanation
The half-life refers to the time it takes for half of a sample of a radioactive isotope to decay and form a daughter isotope. It is a measure of the stability of the isotope and can be used to determine the age of rocks or artifacts through a process called absolute dating. The concept of half-life is crucial in understanding radioactive decay and is widely used in various scientific fields, including geology and archaeology.
10.
Another name for a radioactive isotope:
Correct Answer
A. Parent isotope
Explanation
A parent isotope refers to a radioactive isotope that undergoes radioactive decay and produces a daughter isotope. The parent isotope is the original unstable isotope before it transforms into a more stable form, which is the daughter isotope. The terms "son isotope" and "grandmother isotope" do not accurately describe the relationship between radioactive isotopes and are not commonly used in scientific literature.
11.
A radioactive isotope is stable.
Correct Answer
B. False
Explanation
A radioactive isotope is not stable because it undergoes radioactive decay, which means it spontaneously emits radiation and transforms into a different element or isotope. This process continues until the isotope reaches a stable state. Therefore, the correct answer is False.
12.
Older rocks lie above younger rocks.
Correct Answer
B. False
Explanation
The statement contradicts the basic principle of stratigraphy, which states that younger rocks are found above older rocks. This principle is based on the understanding that sedimentary rocks are formed in layers over time, with each new layer being deposited on top of the previous layers. Therefore, older rocks are typically found deeper in the Earth's crust, while younger rocks are closer to the surface.
13.
Catastrophism is the idea that geologic change happens suddenly.
Correct Answer
A. True
Explanation
Catastrophism is a geological theory that suggests that major changes in the Earth's surface, such as earthquakes or volcanic eruptions, occur suddenly and are caused by catastrophic events. This theory contrasts with uniformitarianism, which proposes that geological changes happen gradually over long periods of time. Therefore, the statement that catastrophism is the idea that geologic change happens suddenly is true.
14.
A paleobotanist studies fossilized insects.
Correct Answer
B. False
Explanation
A paleobotanist is a scientist who studies fossilized plants, not insects. Therefore, the correct answer is False.
15.
Animals take in Carbon-14 by eating plants.
Correct Answer
A. True
Explanation
Animals take in Carbon-14 by eating plants because plants undergo photosynthesis, which involves the absorption of Carbon-14 from the atmosphere. As animals consume plants as a source of food, they also ingest the Carbon-14 present in the plants. This allows Carbon-14 to enter the animal's body and become part of its tissues. Therefore, the statement "Animals take in Carbon-14 by eating plants" is true.