Chapter 10

Question 1

When did the Sun form?

Answer 1

at around the same time as the planets

Question 2

What process contributed to the formation of Earth’s early atmosphere?

Answer 2

outgassing

The transfer of gases from Earth’s mantle to the atmosphere by volcanic eruptions.

Question 3

In what era did Pangea form?

Answer 3

paleozoic era

Question 4

During which time did flowering plants appear?

Answer 4

mesozoic era

Question 5

What is the order of the eras in the geologic time scale from oldest to youngest?

Answer 5

palaozoic, mesozoic, cenozoic

Question 6

What is the name of a scientist who studies past life on earth?

Answer 6

paleontologist

Question 7

What is a nebula?

Answer 7

a mixture of dust and gas

Question 8

Which is the smallest unit of geologic time?

Answer 8

epoch

Question 9

processes changed Earth’s atmosphere to be more oxygen-rich?

Answer 9

radiation from the sun splitting water and photosynthesis

Question 10

Which was NOT a source of heat for early Earth?

Answer 10

hydorthermal energy

Question 11

Which time period is known as the age of mammals?

Answer 11

cenozoic era

Question 12

When did the first multicellular organisms appear on Earth?

Answer 12

between 1 and 2 billion years ago

Question 13

When did life first appear?

Answer 13

precambrian era

Question 14

arth formed when __________ caused small pieces of rock and metal to smash together and create the planet.

Answer 14

gravity

Question 15

Which gas was in high concentrations in the early atmosphere and later condensed to form Earth’s oceans?

Answer 15

water vapor

Question 16

Many animals were alive millions of years ago, but are now extinct. What is the most likely cause of extinction?

Answer 16

The organisms couldn’t adapt to their environment.

Question 17

gases is NOT released during volcanic eruptions?

Answer 17

oxygen

Question 18

Complete the sentence. Earth separated into layers based on ____.

Answer 18

density

Question 19

What is Earth’s approximate age?

Answer 19

4.6 billion yrs

Question 20

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.

Answer 20

Cyanobacteria added oxygen to the atmosphere.

Question 21

What was one of the earliest forms of life?

Answer 21

cyanobacteria

Question 22

What is the densest part of planet Earth?

Answer 22

core