Why Do You Need Oxygen? (What Role Does O₂ Play

question 5

Multiple Choice

Why do you need oxygen? (What role does O₂ play in aerobic respiration?)

• A)It is the final electron acceptor at the end of the electron transport chain.
• B)It combines with acetyl-CoA at the start of the citric acid cycle.
• C)It is given off as a by-product during the oxidation of pyruvate.
• D)It combines with H₂O to help drive the formation of ATP.

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Definitions:

Foetal Stage

The period in human development that begins from the ninth week after fertilization and continues until birth, characterized by rapid growth and maturation of organs and bodily systems.

Embryonic Stage

A phase of prenatal development that occurs from the second to the eighth week after fertilization, during which major body structures and organ systems begin to develop.

Germinal Stage

The initial two weeks of prenatal development after conception, characterized by cell division and the attachment of the zygote to the uterine wall.

Neonatal Stage

The period extending from birth to 28 days of life, characterizing the first phase of infancy where intensive care and monitoring are essential.