Proton Pumps Are Used in Various Ways by Members of Every

question 24

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 pumps are an essential feature of all cell membranes.
• C)Proton gradients across a membrane were used by cells that were the common ancestor of all three domains of life.
• D)Cells of each domain evolved proton pumps independently when oceans became more acidic.

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Definitions:

Frequency

In the context of waves, it refers to the number of cycles or vibrations per unit of time, often measured in Hertz (Hz).

Photoreceptors

Cells in the retina of the eye that are sensitive to light and convert it into signals that can lead to visual perception.

Brightly Lit

An environment or area that is well illuminated with light, often used to describe spaces designed to enhance visibility.

Colors

Visual properties perceived by the eye and brain due to the way an object reflects or emits light, often evoking psychological and emotional responses.