The Origins and Early Evolution of Life on Earth

The video explores the origins of life, starting with early oceans rich in organic compounds, which served as the building blocks for the first unicellular organisms. These early life forms were heterotrophs and prokaryotes. Stromatolites, the oldest known fossils, provide evidence of early bacterial life. Around 2.5 billion years ago, autotrophs emerged, using photosynthesis to produce food and release oxygen, transforming Earth's atmosphere into an oxygen-rich environment.

What element is a key component of organic compounds found in the early oceans?

• Hydrogen

• Nitrogen

• Oxygen

• Carbon

What type of cells were the first living organisms on Earth?

• Unicellular prokaryotes

• Multicellular eukaryotes

• Multicellular prokaryotes

• Unicellular eukaryotes

What are stromatolites?

• Fossilized remains of bacterial mats

• Fossilized remains of fungi

• Fossilized remains of animals

• Fossilized remains of plants

How did early autotrophs produce their own food?

• By consuming other organisms

• By breaking down rocks

• By absorbing nutrients from water

• By using sunlight in photosynthesis

What significant change did early autotrophs bring to Earth's atmosphere?

• Decreased carbon dioxide levels

• Increased nitrogen levels

• Decreased hydrogen levels

• Increased oxygen levels