The Excavates Constitute a Clade of Eukaryotes That Includes Groups

question 103

Multiple Choice

The excavates constitute a clade of eukaryotes that includes groups without mitochondria.Which of the following is the most convincing evidence that this absence of mitochondria is a derived condition resulting from a secondary loss?

• A) There is a nuclear membrane in these organisms.
• B) The cell membrane of these organisms is flexible and capable of phagocytosis.
• C) Some of the nuclear genes of these organisms are normally associated with mitochondria.
• D) In euglenids, a group in this clade with mitochondria, the mitochondria have distinctive disc-shaped cristae.
• E) Other eukaryote clades have both chloroplasts and mitochondria.

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