Given the original mRNA codon “UAC”, what is an example of a mRNA codon that would result in a silent mutation?

In mutation 1, the codon CUC changes to CUU. As both the codons code for the same amino acid i.e., leucine, thus, this mutation is silent mutation and does not affect individual having it.

In mutation 2, a base G is inserted between codons CAU and CUU and changes the frame of reading of genetic code and changes the entire polypeptide coded by it. It is a frameshift mutation.

In mutation 3, codon UAC is changed into a termination codon UAA which stops polypeptide synthesis, hence such type of mutation is called nonsense mutation.

So, the correct answer is 'Silent mutation → 4 Frameshift mutation → Nonsense mutation'.

cells use diffusion to get substances in and out of themselves. that diffusion will occur across the cell membrane or the outer covering of the cell. because we are talking about the surface of the cell, surface area and volume are  important factors here. as a cell increases in size, its surface area and volume increase as well.  we call that the surface area to volume ratio (sa: vol).  but the catch is that  volume increases at a greater rate than surface  area. in other words, as a cell gets bigger, the sa: vol gets smaller. so a really small cell like bacteria is mostly cell membrane (surface) with very little contents (volume). a really big cell like an egg, is mostly insides with a super thin membrane. so what ends up happening is that the cell cannot efficiently diffuse all of the stuff it needs in/out to survive. therefore cell size is limited to about 100mm. so how do we make organisms bigger than 100mm? cells divide! by dividing and becoming multicellular, organisms are able to grow!   check out the diagrams i attached to see the effect of sa: vol. i hope this ! good luck!