Fossils are the remains and traces of ancient plant and animal lives that are more than 10,000 years old. They range in size from microscopic structures to dinosaur skeletons and complete bodies of enormous animals. Skeletons of extinct species of human are also considered fossils.
An environment favorable to the growth and later preservation of organisms is required for the occurrence of fossils. Two conditions are almost always present: The possession of hard parts, either internal or external, such as bones, teeth, scales, shells, and wood; these parts remain after the rest of the organism has decayed. Organisms that lack hard parts, such as worms and jelly fish have left a meager geologic record. Quick burial of the dead organism, so that protection is afforded against weathering, bacterial action, and scavengers.
Nature provides many situations in which the remains of animals and plants are protected against destruction. Of these, marine sediment is by far th
A. photographed.
B. uncovered.
C. located.
D. appeared.
Fossils are the remains and traces of ancient plant and animal lives that are more than 10,000 years old. They range in size from microscopic structures to dinosaur skeletons and complete bodies of enormous animals. Skeletons of extinct species of human are also considered fossils.
An environment favorable to the growth and later preservation of organisms is required for the occurrence of fossils. Two conditions are almost always present: The possession of hard parts, either internal or external, such as bones, teeth, scales, shells, and wood; these parts remain after the rest of the organism has decayed. Organisms that lack hard parts, such as worms and jelly fish have left a meager geologic record. Quick burial of the dead organism, so that protection is afforded against weathering, bacterial action, and scavengers.
Nature provides many situations in which the remains of animals and plants are protected against destruction. Of these, marine sediment is by far th
A. quick burial.
B. cold storage.
C. quick temperature change.
D. lack of water
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Fossils are the remains and traces ( such as footprints or other marks) of ancient plant and animal life that are more than 10,000 years old. They range in size from microscopic structures to dinosaur skeletons and complete bodies of enormous animals. Skeletons of extinct species of humans are also considered fossils.
An environment favorable to the growth and later preservation of organisms is required for the occurrence of fossils. Two conditions are almost always present: (1) The possession of hard parts, either internal or external, such as bones, teeth, skulls, shells, and wood; these parts remain after the rest of the organism has decayed. Organisms that lack hard parts, such as worms and jellyfish, have left few geologic records. (2) Quick burial of the dead organism, so that protection is afforded against weathering, bacterial action, etc.
Nature provides many situations in which the remains of animals and plants are protected against
A. in a deep lake.
B. covered by sediment.
C. protected by oil.
D. buried slowly.
In ancient times the most important examinations were spoken, not written. In the schools of ancient Greece and Rome, testing usually consisted of saying poetry aloud or giving speeches.
In the European universities of the Middle Ages, students who were working for advanced degrees had to discuss questions in their field of study with people who had made a special study of the subject. This custom exists today as part of the process of testing candidates for the doctor’s degree. Generally, however, modern examinations are written. The written examination, where all students are tested on the same questions, was probably not known until the nineteenth century. Perhaps it came into existence with the great increase in population and the development of modern industry. A room full of candidates for a state examination timed exactly by electric clocks and carefully watched over by managers, resembles a group of workers at an automobile factory. Certainly, during
A. should test only opinions
B. should always be written
C. has changed since the Middle Ages
D. is given only in factories
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