<span>The answer is (D)-when the rate of the forward and reverse reactions are equal.</span>
Answer:
In order to determine the rate at which the sediment layers were deposited
Explanation:
Iridium is an important element that belongs to the Platinum group and they are dominantly present in the asteroids and comets. They are the key evidence that suggests the occurrence of an asteroidal impact or a mass extinction event that has taken place in the geological past.
The presence of Iridium mixed with the clay sediments in the boundary between the Cretaceous and Tertiary (K-T boundary) suggested the mass extinction event that wiped out numerous life forms from the earth.
The famous scientist Dr. Luis Walter Alvarez suggested measuring the concentration of Iridium in this K-T boundary in order to determine the rate at which these sediment layers were deposited. They were able to determine that these Iridium elements were present due to the asteroid impact on earth, that wiped out the dinosaurs from the earth. They also considered that this element can be produced from the eruptions of volcanoes.
Answer:
The carbons of the acetyl group oxidize which generate CO2, and in turn H2O.
Explanation:
The pyruvic acid that is generated during glycolysis enters the mitochondria. Inside this organelle, the acid molecules undergo a process called oxidative decaborxylation in which an enzyme of several cofactors is involved, one of which is coenzyme A. Pyruvic acid is transformed into an acetyl molecule and these are been introduced to the begining of the Krebs Cycle where the acetyl-group (2C) from acetyl-CoA is transferred to oxaloacetate (4C) to produce citrate (6C). As the molecule cycles the two carbons of the acetyl oxidize and are released in the form of CO2. Then the energy of the Krebs cycle becomes sufficient to reduce three NAD +, which means that three NADH molecules are formed. Although a small portion of energy is used to generate ATP, most of it is used to reduce not only the NAD + but also the FAD which, if oxidized, passes to its reduced state, FADH2
