Some Microbes Use Non-O₂ Electron Acceptors to Complete the Electron

question 65

Multiple Choice

Some microbes use non-O₂ electron acceptors to complete the electron transport chain.An example of an organism that carries out this type of electron transport is a soil bacterium that takes in nitrate (NO₃⁻) and releases nitrogen gas (N₂) .The nitrate functions as a(n)

• A) energy source.
• B) electron acceptor.
• C) source of electrons.
• D) fuel molecule.
• E) respiratory chain component.

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Definitions:

Population Size

The total number of individuals within a defined area at a given time.

Molecular Phylogenetic Studies

Investigations that use molecular data, such as DNA sequences, to infer the evolutionary relationships among species.

Human Genetic Diversity

The variation in genetic makeup among individuals within the human species.

Monophyletic Group

A set of organisms that consists of all the descendants of a common ancestor.