In determining probabilities all you need to do is count and then divide by the number of results.
It is asking the chances of having green seeds and that's the recessive allele. For recessive traits to be expressed, there can't be a dominant trait next to it because the dominant trait will always be expressed. So the expected result should be yy (two lowercase) if you want the recessive trait to be expressed.
In the Punnett square of the second generation, there is 1 out of 4 yy genotype. So then divide 1 by 4 and multiply it by 100% to get the probability in percent.
So in short, the answer is 25%.
Proteins
u have to know that proteins are synthesized from basic units called amino acids. (think small Lego blocks forming a huge structure)
the process is called condensation.
there are 20 essential amino acids which we require for our daily body use. these amino acids molecular makeup COULD consist of those elements which you mentioned in your question.
hydrogen, carbon, oxygen and nitrogen elements are ALWAYS present in all amino acids. certain types of amino acids consist of phosphorus or even sulfur elements.
It least walk,stand,protects your organs, and the marrow makes blood cells