How a single-celled organism almost wiped out life on Earth

Cyanobacteria were the first oxygen producing photosynthesizers. They evolved between __ and __ billion years ago.

• 0.5 – 1.5

• 2.5 – 3.5

• 4.5 – 5.5

• >6

Tags

NGSS.HS-LS4-1

NGSS.HS-LS4-2

The Great Oxygenation event was caused by a change in oxygen composition in the atmosphere, where the amount of oxygen:

• Stayed the same

• Increased

• Decreased

The first great extinction occurred because:

• Oxygen is toxic to anaerobic organisms

• The temperature on earth changed drastically

• Carbon-dioxide is toxic to anaerobic organisms

• Volcanic eruptions clouded the sun

Tags

NGSS.HS-LS4-5

The Huronian Glaciation:

• Was the first Ice Age on Earth

• Was the longest Ice Age

• Caused a Snow Ball Earth

• All of the above

Tags

NGSS.HS-ESS2-1

NGSS.HS-ESS2-4

NGSS.HS-ESS3-5

Before cyanobacteria, oxygen on Earth was:

• Locked in molecules

• Locked in the ocean

• Not present on Earth

• In the atmosphere in low concentrations

Cyanobacteria became organelles in the cells of these modern organisms

• plants

• gorillas

• humans

• dinosaurs

Tags

NGSS.HS-LS4-1

NGSS.HS-LS4-2

Cyanobacteria are unicellular which means that they

• are made of multiple cells

• are made of only one cell

• are not made of cells

Tags

NGSS.MS-LS1-1

The glaciation event occurred after the release of oxygen turned methane into carbon dioxide and water because

• methane is a stronger greenhouse gas and kept the planet warmer

• methane is a weaker greenhouse gas and kept the planet cooler

Tags

NGSS.HS-ESS2-4

What percentage oxygen is our atmosphere today?

• 100%

• 50%

• 75%

• 21%

Are cyanobacteria still around today?

• Yes

• No