Answer:
The correct answer will be option-B (purine).
Explanation:
Nucleic acid structure is made up of monomer unit called nucleotide. Each nucleotide is composed of a five-carbon sugar, a phosphate group and five types of nitrogenous bases.
The nitrogenous bases are categorized in two forms the purines (adenine and guanine ) and the pyrimidines (cytosine, thymine and uracil). The "purines" contain double rings in their structure due to which they appear larger in size than pyrimidines which are made up of single rings.
Thus, Option-B is the correct answer.
The number of protons in a neutral atom equals the number of ELECTRONS.
Answer:
development of an osmotic pressure difference across capillary walls
Answer:
Both gray wolves and killer whales have live births. And Both gray wolves and killer whales are carnivores
Explanation:
Answer:
The endosymbiotic theory
Explanation:
Protists are the multicellular organisms which possess characteristics of both the prokaryotes and eukaryotes.
The protist can derive nutrition by either heterotrophic mode or photoautotrophic mode. This variation could exist within the same genus and same species.
This variation could be explained with the endosymbiotic origin of the organisms as some species could engulf the photosynthetic bacteria whereas some could have engulfed the chemosynthetic bacteria.
This can be observed in the green and red algae which depend on a different mode of nutrition belonging to the same group.
Thus, the endosymbiotic theory is correct.
