Which of the Following Statements Best Explains the Observation That

question 12

Multiple Choice

Which of the following statements best explains the observation that proton pumps are used by organisms in every domain of life?

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

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Definitions:

Adonis Syndrome

A psychological condition where an individual is excessively preoccupied with their body image and muscularity, often leading to compulsive exercising and bodybuilding.

Objective Self-awareness

A state in which individuals view themselves as objects of others' attention and are critically aware of themselves from an external perspective.

Body Image

An individual's perception of the aesthetics or sexual attractiveness of their own body, which can influence self-esteem and mental health.

Subjective Evaluation

A process of assessing or making judgments based on personal feelings, tastes, or opinions rather than external criteria or factual evidence.