Answer:
Thiamine pyrophosphate (derived from vitamin B1) is a coenzyme required for the activity of pyruvate dehydrogenase enzyme complex.
Explanation:
Pyruvate is the end product of glycolysis. During aerobic cellular respiration, pyruvate is oxidatively decarboxylated into acetyl CoA which in turn enters the Kreb's cycle. Oxidative decarboxylation of pyruvate is carried out by enzyme complex pyruvate dehydrogenase (PDH). The first step is simple decarboxylation and is catalyzed by pyruvate decarboxylase of the PDH complex.
The enzyme pyruvate decarboxylase and has a tightly bound coenzyme, thiamine pyrophosphate. Thiamine pyrophosphate is derived from vitamin B1. Lack of vitamin B1 in the human diet leads to beriberi that is characterized by an increased concentration of pyruvate in blood urine since oxidative decarboxylation cannot occur due to lack of the coenzyme thiamine pyrophosphate.
Biomes, biodiversity, wetlands, permafrost, and estuary
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.