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Which of the following is a distinction between the Krebs cycle in eukaryotes and prokaryotes?

A. Prokaryotes do not use acetyl CoA.
B. The process occurs in the cytoplasm of Eukaryotes.
C. The process occurs in the mitochondria of Eukaryotes.
D. Eukaryotes do not produce carbon dioxide.
E. Prokaryotes do not produce FADH2.

User Palindrom
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Answer:

C. The process occurs in the mitochondria of Eukaryotes.

Step-by-step explanation:

  • In eukaryotes: glycolysis takes place within cytosol, Krebs cycle within mitochondrial matrix & ETC within inner mitochondrial membrane. Prokaryotes undergo binary fission(only cytokinesis) & conjugation.
  • Prokaryotes undergo binary fission(only cytokinesis) & conjugation. Eukaryotes perform mitosis, meiosis(both karyokinesis and cytokinesis).

Therefore in prokaryotic cells, the citric acid cycle occurs in the cytoplasm; in eukaryotic cells, the citric acid cycle takes place in the matrix of the mitochondria.

Acetyl-CoA reacts in the first step of the eight step sequence of reactions that comprise the Krebs cycle, all of which occur inside mitochondria of eukaryotic cells. While the Krebs cycle does produce carbon dioxide, this cycle does not produce significant chemical energy in the form of adenosine triphosphate (ATP) directly, and this reaction sequence does not require any oxygen. Instead, this cycle produces NADH and FADH2, which feed into the respiratory cycle, also located inside of the mitochondria. It is the respiratory cycle that is responsible for production of large quantities of ATP and consumption of oxygen. In addition, the respiratory cycle converts NADH and FADH2 into reactants that the Krebs cycle requires to function. Thus, if oxygen is not present, the respiratory cycle cannot function, which shuts down the Krebs cycle. For this reason, the Krebs cycle is considered an aerobic pathway for energy production.

Hope this helps!

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User Jfdoming
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