Geologic Time Practice 2

What was a key feature of the Hadean Eon?

• Life first appeared on Earth

• The Earth's crust cooled and solidified

• Complex life forms developed

• Oxygen started to accumulate in the atmosphere

What event is associated with the Hadean Eon?

• The formation of Earth's moon

• The appearance of multicellular organisms

• The first land plants

• The extinction of the dinosaurs

Why is there no known life from the Hadean era?

• There was not enough water on Earth

• Earth's surface was too hot and unstable for life

• Oxygen levels were too high

• Complex organisms had not yet evolved

What happened during the Archean Eon

• The first multicellular organisms appeared

• The moon was formed

• The first life forms, simple bacteria, appeared

• Complex life forms evolved, like animals and plants

What was Earth's atmosphere mostly composed of in the Archean Eon?

• oxygen and nitrogen

• methane and ammonia

• carbon dioxide and oxygen

• nitrogen and sulfur

What was an important development during the Archean Eon?

• The formation of continents

• The appearance of dinosaurs

• The first evidence of photosynthesis

• The development of writing

Why is the Proterozoic Eon significant?

• It marks the beginning of Earth's cooling

• It is when oxygen began accumulating in the atmosphere

• It is when the first invertebrates appeared

• It includes the extinction of dinosaurs

Which of the following organisms first appeared during the Proterozoic Eon?

• Sponges and algae

• Dinosaurs

• Flowering plants

• Amphibians

The first evidence of multicellular organisms appears in the Proterozoic Eon. What type of organisms were they?

• Amphibians

• Dinosaurs

• Sponges and simple algae

• Reptiles

The Phanerozoic Eon began around 543 million years ago. What makes this eon different from previous ones?

• It was the first time Earth's crust solidifed

• Complex life, like plants and animals, formed

• It was a time of massive volcanic eruptions

• It was the era when Earth was first forming