The correct answer to this question is this one: they lacked oxygen. The earliest organisms were completely heterotrophic in nature because of the reason that they lacked oxygen. <span>A heterotroph is an organism that cannot fix carbon and uses organic carbon for growth. </span>
Answer:
A mutation can occur when mistakes are made during DNA replication.
Explanation:
Classification of Adenine is given below.
Explanation:
- Adenine is one of the four bases that make up DNA. It corresponds to the letter A of the sequence that combines A, C, G and T in the DNA. Adenine has the property that, when it is in the double helix, it is always forming a pair with the thymine of the opposite strand.
- Adenine is one of the five nitrogenous bases that are part of nucleic acids (DNA and RNA) and in the genetic code is represented by the letter A. The other four bases are guanine, cytosine, thymine and uracil. Adenine is always paired with thymine in DNA.
- A chemical compound that cells use to make the fundamental elements of DNA and RNA. It is also part of many substances in the body that provide energy to cells. Adenine is a type of purine. DNA structure.
- The adenine formula, which is derived from purine, is C5H5N5. It is a component of the nucleic acid chains that is in the nucleotides, as is the rest of the nitrogenous bases of RNA and RNA (uracil, thymine, cytokine and guanine).
- Cytosine (C) is one of the four bases of DNA, the other three being adenine (A), guanine (G) and thymine (T). Within the DNA molecule, the cytosine bases are located in a chain forming chemical bonds with the guanine bases of the opposite chain
- Adenine and thymine are complementary (A = T), linked by two hydrogen bridges, while guanine and cytosine (G≡C) are linked by three hydrogen bridges. Since RNA does not contain thymine, complementarity is established between adenine and uracil (A = U) by two hydrogen bridges.
Plowing with machines, irrigating with drip systems, and these are all modern agricultural methods.
