Refer to the Graph Showing Variations in Oxygen Levels During

question 13

Multiple Choice

Refer to the graph showing variations in oxygen levels during Earth's history. Which of the following can be concluded from the graph?

• A) Increased atmospheric oxygen levels coincided with a decrease in insect size.
• B) Multicellularity preceded the evolution of photosynthesis.
• C) The first forms of life on Earth did not use oxygen.
• D) Overall, atmospheric oxygen levels have decreased over Earth's history.
• E) The first flowering plants required giant flying insects for pollination.

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Definitions:

Elastic

Materials or tissues capable of returning to their original shape after being stretched or compressed.

Reticular

Related to a network or net-like structure, often used in biological contexts to describe the appearance or organization of tissues or cell formations.

Lesbian Mothers

Female same-sex partners who are raising children together, focusing on the dynamics and outcomes in parent-child relationships.

Gay Fathers

Men who identify as gay and have taken on the role of being a parent or guardian to a child.