Apentix/AP Biology/Unit 2: Cell Structure and Function/Question
AP Biologymediummcq1 pt

Both bacterial plasma membranes and mitochondrial inner membranes can contain electron-transport chains. Which interpretation is most consistent with the endosymbiotic theory?

A.Mitochondria descended from bacterial ancestors that already used membrane-based electron transport.
B.All eukaryotic internal membranes formed directly by folding of the bacterial plasma membrane.
C.Bacteria acquired their plasma membranes from modern mitochondria.
D.Electron transport requires a nucleus, so bacteria cannot perform it.

Explanation

Core Concept

Endosymbiotic theory proposes that mitochondria descended from bacteria incorporated into an ancestral host. The shared use of membranes for respiratory electron transport is consistent with that ancestry; it does not imply that every eukaryotic internal membrane arose by the same mechanism.

Correct Answer

AMitochondria descended from bacterial ancestors that already used membrane-based electron transport.

More Unit 2: Cell Structure and Function practice questions

Try a random question →

Practice more AP Biology questions with full explanations

Practice Unit 2: Cell Structure and Function Questions →