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:

Procrastination

The action of delaying or postponing tasks, often leading to stress, anxiety, and reduced productivity.

Underutilization

Refers to the failure to use something or someone to its fullest potential or capacity, often resulting in wasted resources or talents.

Time

A continuous, measurable sequence of events moving from past through present to future.

Group Accountability

The shared responsibility among members of a group for the outcomes or achievements of the group as a whole.