Giardia Is Eukaryotic Yet Is Long Thought to Lack a Mitochondira

question 32

Multiple Choice

Giardia is eukaryotic yet is long thought to lack a mitochondira. Recently, researchers have found that each Giardia cell contains double membrane- bound organelles similar to a mitochondria called mitosomes that lack mtDNA. What is the best explanation for mitosomes?

• A) Mitosomes are more advantageous to eukaryotes than mitochondria.
• B) Mitosomes evolved from another Giardia organelle that lacked DNA.
• C) Mitochondria in Giardia evolved into mitosomes and have lost or transferred their DNA to the Giardia nuclear genome.
• D) Giardia are asexual and thus do not require mitochondria with its own DNA.
• E) Mitosomes are the ancestral form of the mitochondria.

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Definitions:

Initial Cost

The original outlay or expense associated with acquiring an asset or launching a project, not including operational or maintenance costs.

Internal Rate of Return

The rate of return that brings the total net present value of a project's cash flows to zero.

Investment

Investment is the allocation of resources, typically money, with the expectation of generating an income or profit.

Internal Rate of Return

A metric used in capital budgeting to estimate the profitability of potential investments, representing the rate of return at which the net present value of costs and benefits of the project equals zero.