The answer is field investigation.
<span>A field investigation includes observation of
free-living animals in their natural habitat without affecting them, their
behavior, or their habitat. So, observation of tigers' activity in their native habitat is an example of the field investigation. The investigator would simply observe their behavior, not affecting the tigers in any way.</span>
Answer:
ITS B
Explanation:
to exchange oxygen with carbon dioxide
<span>Cancerous tumors are divided into broad groups on the basis of the particular type of tissue from which the tumor cells arise. this is called histogenesis.
</span><span>Tumors are of different types, some are cancerous and some are benign (non-cancerous). In a disease of cancer, there is an abnormal cell growth. It is characterized as out of control cell growth.</span>
Answer:
b. Nucleotides
Explanation:
Nucleic acids are examples of structures formed from nucleotides. And in relation to the composition of DNA, we have the formation of the largest cellular macromolecule, all formed by nucleotides.
The nucleotide is a group formed by the association of 3 molecules - a nitrogen base, a phosphate group and a pentose glycide. Thus, we may have variations within these ligands, such as: in DNA we have the presence of pentose deoxyribose, while in RNA we have the presence of pentose ribose.
The nucleotides have differences in relation to its nitrogen base, which can be purine or pyrimidine. Purine bases vary in Adenine and Guanine, while pyrimidine bases are classified in Thymine, Uracil and Cytosine. Purine and pyrimidine bases are complementary and each have specific binders. Thus, we have that the purine base Adenina, binds with the pyrimidine bases Timina and Uracila, while the base Guanina binds exclusively to Cytosine and vice versa.