Proton Pumps Are Used in Various Ways by Members of Every

question 69

Multiple Choice

Proton pumps are used in various ways by members of every domain of organisms: Bacteria, Archaea, and Eukarya. What does this most probably mean?

• A) Proton pumps must have evolved before any living organisms were present on Earth.
• B) Proton gradients across a membrane were used by cells that were the common ancestor of all three domains of life.
• C) The high concentration of protons in the ancient atmosphere must have necessitated a pump mechanism.
• D) Cells of each domain evolved proton pumps independently when oceans became more acidic.
• E) Proton pumps are necessary to all cell membranes.

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Definitions:

Unschooled Peers

Individuals, typically children or adolescents, who acquire their education and socialization outside of formal school settings.

Instructional Discourse

The structured communication or dialogue that takes place within educational settings, focused on imparting knowledge or skills.

Shirley Heath

A researcher in the field of linguistic anthropology, notable for her work on the ways in which language use varies according to social context and contributes to identity formation.

Home Discourse

The way in which families communicate and interact within the home, influencing children's linguistic and social development.