Early Earth History

The Precambrian time period is segmented into very few parts because: a. the fossil record is scarce c. cyanobacteria were the only life form b. life did not exist d. volcanic activity ruined the fossil record

The Precambrian time period is the largest on the geological time scale. TRUE OR FALSE

A life-form in the Precambrian time was ____. a. cyanobacteria c. reptiles b. humans d. dinosaurs

Life-forms that existed during the Paleozoic Era included ____. a. fish c. reptiles b. trilobites d. all of the above

Animal life in the Paleozoic Era included all of the following EXCEPT ____. a. marine life c. amphibians b. humans d. reptiles

Cyanobacteria increased the levels of carbon dioxide in the atmosphere. TRUE OR FALSE

The formation of the moon may have caused the Paleozoic extinction. TRUE OR FALSE

The change in environments that may have occurred at the end of the Paleozoic Era may have been caused by ____. a. mass extinctions c. plate tectonics b. evolution of the dinosaurs d. the beginning of an ice age

Little is known about much of Earth's early history because ____. a. Precambrian rocks have been deeply buried b. Precambrian rocks have been changed by heat and pressure c. Precambrian soft-bodied life-forms weren't often preserved as fossils d. all of the above

The development of ____ factored in the development of complex organisms. a. ozone c. cyanobacteria b. oxygen d. all of the above