Answer:
It is the arrangement of nucleotide within the genes which differs among DNA structures of different species. Each gene contains several codons which is three nucleotide long
Structure X is only found in plant cells, and structure Y is found in plant and animal cells.
I don't think the water cycle has a beginning or ending because all the water in the world is always in various stages of the cycle. It's kind of like asking if a circle has a beginning or ending.
At the very least, I can't think of a specific 'beginning' or 'ending', although I suppose there is an argument to be made that percipitation is the ending and evaporation is the beginning.
Answer:
A
Explanation:
in the biological sequence the respiratory does not occur the cells of the human body