Answer:
C. Nucleotides
Explanation:
Nucleic acids are macromolecules which are polymers of nucleotides. There are two types of nucleic acids namely: deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Nucleotides are the building blocks of nucleic acids.
A nucleotide is made up of three components:
- A phosphate group
- A five carbon sugar called pentose sugar. In RNA the sugar is ribose sugar and in DNA the sugar is deoxyribose sugar.
- Nitrogenous bases: There are four different types of bases in DNA: adenine, guanine, cytosine and thymine. In RNA thymine is replaced by uracil. Adenine and guanine are purines whereas cytosine, thymine and uracil are pyrimidines.
Nitrogenous base and sugar together are called nucleoside and when phosphate is also attached then it is called nucleotide.
Answer:
c. the sun
Explanation:
The sun is the most basic source of energy for all living beings. It supports photosynthesis in plants and algae that is the main reaction for producing energy rich compounds like carbohydrates etc. These compounds are utilized by all life on Earth to stay alive.
Answer: cellular metabolism
Explanation:
Cellular metabolism is chemical reactions that takes place in living organisms so that they will be able to maintain life. Cellular metabolism is made up of thousands of genes, metabolites and proteins.
Cellular metabolism is affected by the sympathetic nervous system but is not affected by the parasympathetic nervous system.
