Origin Of Compartmentalization

Which of the following groups of cellular components are found in eukaryotic cells but not prokaryotic cells?

• Ribosomes, a nucleus, and chloroplasts

• Circular chromosomes, mitochondria, and an endoplasmic reticulum

• A nucleus, ribosomes, and cell walls

• An endoplasmic reticulum, mitochondria, and a nucleus

Which of the following best supports the statement that mitochondria are descendants of endosymbiotic bacteria-like cells?

• Mitochondria and bacteria possess similar ribosomes and DNA

• Mitochondria and bacteria possess similar nuclei.

• Glycolysis occurs in both mitochondria and bacteria.

• Both mitochondria and bacteria have microtubules.

• Neither mitochondria nor bacteria possess chloroplasts

The endosymbiont theory proposes a model for the evolution of mitochondria. According to the model, an ancestral eukaryote engulfed a small, free-living prokaryotic organism. The engulfed prokaryote then formed an endosymbiotic relationship with the eukaryotic host. Which of the following observations best supports the model?

• Prokaryotes and eukaryotes acquire nutrients from the surrounding environment.

• Organelles such as mitochondria and the endoplasmic reticulum have membranes composed of phospholipids.

• Mitochondria and some prokaryotes share similar metabolic reactions that produce .

• Eukaryotes evolved after prokaryotes and have more complex structures.

Which of the following provides the weakest evidence that mitochondria were once free-living prokaryotes?

• Mitochondrial ribosomes resemble those of prokaryotes.

• Mitochondria have DNA that is circular and does not have associated protein.

• Enzyme pathways on mitochondrial membranes resemble those found on modern prokaryote membranes.

• Mitochondria reproduce by a process similar to binary fission

• Mitochondria and prokaryotes both are found in a variety of sizes

Which of the following is a characteristic of mitochondria and chloroplasts that supports the endosymbiotic theory?

• Both have bacteria-like polysaccharide cell walls

• Both can reproduce on their own outside of the cell.

• Both contain DNA molecules.

• Both contain endoplasmic reticulum and Golgi bodies.

• Both contain ribosomes that are identical to ribosomes of the eukaryotic cytoplasm