Food webs with fewer species are more sensitive to the loss of species and ecosystem disturbances
Cry Shape HeartyAnswer:Cry Shape Hearty
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Cry Shape HeartyExplanation:Cry Shape Hearty
Cry Shape HeartyCry Shape Hearty
The right answer is A.) DNA in mitochondria
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Eukaryotic cells, with their many intracellular organelles, have long been considered progeny of prokaryotes that would have become more complex as a result of genetic mutations. But from the 1960s, biologist Lynn Margulis proposed an alternative explanation that was first received coldly by the scientific community. His endosymbiotic theory, proposed in a more formal way in a 1981 book, proposes that eukaryotic cells as we know them today would be the result of a series of symbiotic associations with different prokaryotes.
Mitochondria and chloroplasts also have their own DNA that is not trapped in a nucleus, which is also the case with prokaryotes. However, the proteins encoded by this DNA do not cover all mitochondrial proteins. The prokaryote is thought to have lost some genes to the nucleus of the cell, a process known as "endosymbiotic gene transfer". For this reason, mitochondria and chloroplasts are now host-dependent for the synthesis of most of their components.
The decay of uranium isotopes is used to provide information about the age of Earth.
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Explanation:</h3>
Isotopes of Uranium U-232, U-233 , U-234 , U-235 , U-236 , U-238 are used as fuel in nuclear reactors or as explosives for nuclear weapons. Uranium 238 is not very radioactive and it constitutes for nearly 99.3% of natural uranium on Earth and has the longest lifetime: its period is 4.5 billion years, about the age of Earth.
Use of radiometric dating techniques help in defining the age of substances (natural or man-made) using the known decay rates of radioactive elements. Each element has an individual decay rate and half life time.
Two Uranium isotopes (U-238 and U-235) are used for radiometric dating. Both the isotopes have different decay rates and half life period. Both are unstable and radioactive. Since two different isotopes produce two different decay clocks (one as a reference to other), it is beneficial in accurately determining the age of samples. The age of earth (rocks or other natural elements) can be easily determined using Uranium isotopes.
Answer:
D. alcohol
Explanation:
Fermentation by microorganisms converts organic materials into alcohol