I'm not 100% sure, but I think that the digestive system excretes solid wastes only and the excretory system excretes liquid wastes only. So the 3rd option is probably correct.
Yes it could be when you breath in helium it is not normal air so,it goes around your voice box and makes it change and it will go away after a 1
The nucleotide triplet that encodes an amino acid is called a codon. Each group of three nucleotides encodes one amino acid. Since there are 64 combinations of 4 nucleotides taken three at a time and only 20 amino acids, the code is degenerate (more than one codon per amino acid, in most cases).
