The Organisms Originally Responsible for Putting Oxygen in Earthʹs Atmosphere

question 17

Multiple Choice

The organisms originally responsible for putting oxygen in Earthʹs atmosphere lived around

• A) 6 billion years ago.
• B) 1.5 million years ago.
• C) 3.5 billion years ago.
• D) 3.5 million years ago.
• E) 2.4 billion years ago.

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Definitions:

Cytoplasm

The jelly-like substance inside cells that holds organelles, in which most cellular activities occur.

Antibodies

Immune system proteins that specifically recognize and bind to foreign antigens, marking them for destruction.

Blood Protein

Proteins present in blood plasma, including antibodies, albumin, and clotting factors, playing various roles in bodily functions.

Clumping

The process by which cells or particles adhere to each other to form clusters, often seen in blood antigens in response to specific antibodies.