A nucleotide consists of three things: A nitrogenous base, which can be either adenine, guanine, cytosine, or thymine (in the case of RNA, thymine is replaced by uracil). A five-carbon sugar, called deoxyribose because it is lacking an oxygen group on one of its carbons. One or more phosphate groups.
Answer:
C. At least five mass-extinction events have occurred during the last 500 million years.
Explanation:
- The history of mass extinct is related to the five mass extinctions that are caused over by the 350 million years n which many species have disappeared in there short geologic time.
- A massive extinction is caused in the Permian Triassic extinction event i.e about 250 mn years ago which on an estimate has killed 90% of the species.
- The Cretaceous–Paleogene extinction event that occurred over 66 million years ago is known to have wiped out the dinosaurs and many other species.
It is the Mid-Atlantic Ridge.
Ans. An isotope of Hydrogen called Tritium has one Proton and two Neutrons and its mass is 1
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The matrix (inside mito) has a negative charge compared to the intermembrane space (outside of mito but still inside) because positively charged protons are constantly pumped from the matrix to the intermembrane space. A cell oxidizes an organic molecule producing 3 NADH molecules and 3 FADH2 molecules..