What is the evolutionary significance of the mitochondria?
Mitochondria are best known for their role in the generation of ATP by aerobic respiration. Yet, research in the past half century has shown that they perform a much larger suite of functions and that these functions can vary substantially among diverse eukaryotic lineages.
How does the structure and function of mitochondria support the endosymbiotic theory?
Explanation: Bacteria, a prokaryote, has circular DNA, as do mitochondria and chloroplasts. This provides support for the Endosymbiotic Theory, which states that the mitochondria and chloroplast in eukaryotic cells were once aerobic bacteria (prokaryote) that were ingested by a large anaerobic bacteria (prokaryote).
Is endosymbiosis responsible for mitochondria?
A symbiotic relationship where one organism lives inside the other is known as endosymbiosis. Primary endosymbiosis refers to the original internalization of prokaryotes by an ancestral eukaryotic cell, resulting in the formation of the mitochondria and chloroplasts.
How does the endosymbiotic theory relate to evolution?
Explanation: Darwinian evolution proposes that all living organisms are formed by descent with modification from a common ancestor or cell. Endosymbiosis explains the origins of Eukaryotic cells by the theory that one prokaryotic cell absorbed another prokaryotic cell creating a cell with multiple membranes.
Where do mitochondria originate from evolution?
Mitochondria and chloroplasts likely evolved from engulfed prokaryotes that once lived as independent organisms. At some point, a eukaryotic cell engulfed an aerobic prokaryote, which then formed an endosymbiotic relationship with the host eukaryote, gradually developing into a mitochondrion.
What evidence supports the bacterial origin of mitochondria?
There is broad evidence to show that mitochondria and plastids arose from bacteria and one of the strongest arguments to support the endosymbiotic theory is that both mitochondria and plastids contain DNA that is different from that of the cell nucleus and that they have their own protein biosynthesis machinery.
What is the evidence of endosymbiotic theory?
The evidence suggests that these chloroplast organelles were also once free-living bacteria. The endosymbiotic event that generated mitochondria must have happened early in the history of eukaryotes, because all eukaryotes have them. The first eukaryotic cell evolved more than a billion years ago.
What bacteria did mitochondria come from?
The endosymbiotic hypothesis for the origin of mitochondria (and chloroplasts) suggests that mitochondria are descended from specialized bacteria (probably purple nonsulfur bacteria) that somehow survived endocytosis by another species of prokaryote or some other cell type, and became incorporated into the cytoplasm.
What are the steps of endosymbiotic theory?
Terms in this set (6)
- Prokaryotic cell membrane folded into cytoplasm.
- Nuclear membrane, endoplasmic recticulum, and golgi body are now independent of external membrane.
- Ancestoral eukaryote engulfed, but did not kill prokaryote.
- The prokaryote survived inside the eukaryote and each evolved a dependence of each other.
What evidence supports endosymbiotic theory?
The strongest evidence to support the endosymbiotic theory is that the mitochondria and chloroplasts have their own DNA and their DNA is similar to the bacterial DNA.
How would you define endosymbiotic theory?
Endosymbiotic theory is the unified and widely accepted theory of how organelles arose in organisms , differing prokaryotic organisms from eukaryotic organisms. In endosymbiotic theory, consistent with general evolutionary theory, all organisms arose from a single common ancestor.
What is the importance of the endosymbiotic theory?
Endosymbiotic theory is important as it explains the origin of the chroloplast and mitochondria. It also explains the formation of the eukaryotic cells. Endosymbiotic theory explains the origins of eukaryotic cell organelles such as mitochondria in animals and fungi and chloroplasts in plants.
What evidence supports the theory of endosymbiosis?
Another evidence to support the endosymbiotic theory is that the mitochondria and chloroplasts have their own ribosomes. This was the first substantive evidence to hypothesise the endosymbiotic theory.