Chapter 10 Flashcards
When did the Sun form?
at around the same time as the planets
What process contributed to the formation of Earth’s early atmosphere?
outgassing
The transfer of gases from Earth’s mantle to the atmosphere by volcanic eruptions.
In what era did Pangea form?
paleozoic era
During which time did flowering plants appear?
mesozoic era
What is the order of the eras in the geologic time scale from oldest to youngest?
palaozoic, mesozoic, cenozoic
What is the name of a scientist who studies past life on earth?
paleontologist
What is a nebula?
a mixture of dust and gas
Which is the smallest unit of geologic time?
epoch
processes changed Earth’s atmosphere to be more oxygen-rich?
radiation from the sun splitting water and photosynthesis
Which was NOT a source of heat for early Earth?
hydorthermal energy
Which time period is known as the age of mammals?
cenozoic era
When did the first multicellular organisms appear on Earth?
between 1 and 2 billion years ago
When did life first appear?
precambrian era
arth formed when __________ caused small pieces of rock and metal to smash together and create the planet.
gravity
Which gas was in high concentrations in the early atmosphere and later condensed to form Earth’s oceans?
water vapor
Many animals were alive millions of years ago, but are now extinct. What is the most likely cause of extinction?
The organisms couldn’t adapt to their environment.
gases is NOT released during volcanic eruptions?
oxygen
Complete the sentence. Earth separated into layers based on ____.
density
What is Earth’s approximate age?
4.6 billion yrs
Which of the following statements is true?
* Earth’s first atmosphere was made of oxygen.
* Oxygen is only important for breathing.
* The original source of oxygen was volcanoes.
* Cyanobacteria added oxygen to the atmosphere.
Cyanobacteria added oxygen to the atmosphere.
What was one of the earliest forms of life?
cyanobacteria
What is the densest part of planet Earth?
core
