The Earth Takes Shape Astronomy 3.3

Question 1

What might have helped change part of the early atmosphere?

Accepted Answer

elements in comets

Question 2

What may have started forming from molecules in Earth's waters?

Accepted Answer

life forms

Question 3

This is a way organisms make food by using the sun's energy.

Accepted Answer

photosynthesis

Question 4

What makes up most of Earth's atmosphere today?

Accepted Answer

nitrogen and oxygen

Question 5

What protects us from the rays of the sun?

Accepted Answer

ozone layer

Question 6

What is the Earth's surface mostly covered with?

Accepted Answer

water

Question 7

What did planetesimals do as Earth formed?

Accepted Answer

crashed and combined

Question 8

What happened as light rocks piled on Earth's surface?

Accepted Answer

early continents formed

Question 9

This is a gas that is removed from air as organisms make food.

Accepted Answer

carbon dioxide

Question 10

This is a gas that is added to air as organisms make food.

Accepted Answer

oxygen

Question 11

What might have brought some water to the first oceans?

Accepted Answer

icy comets

Question 12

This has a lot of energy and can break apart molecules.

Accepted Answer

ultraviolet radiation

Question 13

What are the continents of Earth made up of?

Accepted Answer

rock

Question 14

What happened as Earth heated up?

Accepted Answer

inner rocks melted

Question 15

What is the thin, outermost layer of Earth?

Accepted Answer

crust

Question 16

What caused a global ocean to form when Earth cooled?

Accepted Answer

rain

Question 17

What heated Earth as it formed?

Accepted Answer

radioactive material

Question 18

What made the early continents move around?

Accepted Answer

energy in the mantle

Question 19

What is the layer beneath the crust?

Accepted Answer

mantle

Question 20

What happened to Earth as gravity crushed rock at its center?

Accepted Answer

it became round

Question 21

What probably changed Earth's early atmosphere?

Accepted Answer

volcanic gases

Question 22

How might water vapor have formed the first oceans?

Accepted Answer

it condensed

Question 23

What is Earth mostly made of?

Accepted Answer

rock

Question 24

What might have made up Earth's early atmosphere?

Accepted Answer

carbon dioxide and water vapor

Question 25

What is the central part of Earth?

Accepted Answer

core

The Earth Takes Shape Astronomy 3.3

Questions 25

The Earth Takes Shape Astronomy 3.3

Questions 25