A nucleotide consists of all of the following except a nitrogenous base. The are of course the main building blocks of genetic information in many life forms.
The correct answer is (d.) proteins. Higher organisms use nitrogen to make their protein. Food that is containing protein also involves nitrogen in it. Protein also has amino acids that contain nitrogen in it which is a necessary essential nutrient for the body.
Answer: The study of plant varieties.
Explanation:
This question relates to the studies that Gregor Mendel, founder of modern genetics, performed at the University of Vienna.
Experimenting on pea plants, Gregor Mendel was able to establish a lot of the rules of heredity that we know today even though his research was not fully appreciated or understood during his own life.
He credited the study of plant varieties to have been most crucial to his final analysis because farmers had been crossbreeding varieties for millennia to bring about better traits in plants.