The mass number is the sum of the number of protons and number of neutrons the atom has.
So, we can write the equation as:
x + 20 = 40
x = 20 neutrons.
Answer: However, most non-canonical genetic codes are inferred from DNA sequence alone, or occasionally DNA sequences and corresponding tRNAs. Because the code governs the translation of nucleotide to amino acid sequences, a code can in principle only be confirmed when both the gene and protein sequences are known
Explanation :DNA is considered a universal genetic code because every known living organism has genes made of DNA. ... Every living organism uses that same system. Basically, every three pieces of DNA becomes one amino acid.
Plants get carbon dioxide<span> from the air through their </span>leaves<span>. The </span>carbon dioxide<span>diffuses through small holes in the underside of the </span>leaf<span> called stomata.</span>
The cell membrane<span> is selectively permeable to ions and organic molecules and controls the movement of substances in and out of </span>cells<span>. The basic function of the </span>cell membrane<span> is to protect the </span>cell<span> from its surroundings. It consists of the phospholipid bilayer with embedded proteins.</span>
