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Nuclein separated in to which components?




Nuclein, discovered by Friedrich Miescher, was later found to consist of two primary components: proteins and nucleic acids. This understanding laid the foundation for the study of DNA and its role in heredity.
Which one of the following is the major component of chromosome?




Chromosomes are primarily composed of nucleic acids and proteins. The major component of chromosomes is nucleic acid, specifically DNA (Deoxyribonucleic Acid) in eukaryotes and most prokaryotes. DNA carries genetic information essential for the growth, development, functioning, and reproduction of all living organisms and many viruses.
Which are the structural units of DNA?




The structural units of DNA are nucleotides. Each nucleotide consists of three components: a nitrogenous base (adenine, thymine, cytosine, or guanine), a pentose sugar (deoxyribose), and a phosphate group. These nucleotides link together to form the long polymer chains that make up DNA.
Which one group is the subunit of nucleotide?




The subunit of a nucleotide consists of three components: a pentose sugar (deoxyribose in DNA or ribose in RNA), a nitrogen base (adenine, thymine, cytosine, guanine in DNA; uracil replaces thymine in RNA), and a phosphoric acid (phosphate group). These components are crucial for the formation of nucleotides, which in turn form nucleic acids like DNA and RNA.
Which of the following will be characteristically different in different living organism?




Nucleic acids (DNA and RNA) are unique to each species and even to each individual within a species due to their unique sequences of nucleotides. Proteins, enzymes, and carbohydrates can be similar across different organisms, but nucleic acid sequences are characteristically different.
What is Ribonucleoside?




A ribonucleoside consists of a ribose sugar and a nitrogenous base. It does not include a phosphate group, which would make it a nucleotide.
Which two sequential carbon number of nucleotides join through phosphodiaster bond?




In nucleotides, the phosphodiester bond forms between the 3' carbon atom of one sugar molecule and the 5' carbon atom of another, linking the nucleotides together in a chain.
What is Guanine?




Guanine is one of the four main nucleobases found in the nucleic acids DNA and RNA. It is a derivative of purine, a double-ringed molecule containing carbon and nitrogen atoms. Specifically, guanine pairs with cytosine in DNA through three hydrogen bonds, contributing to the stability of the DNA double helix.
Ribonucleoside formed from ribonucleotide while:-




Ribonucleosides are formed from ribonucleotides by the removal of the phosphate group. A ribonucleotide consists of a ribose sugar, a nitrogenous base, and a phosphate group. When the phosphate group is removed, the remaining part is called a ribonucleoside, which consists of the ribose sugar and the nitrogenous base.
DNA is localized in which cell organelle?




DNA is primarily localized in the nucleus of eukaryotic cells. However, it is also found in mitochondria and chloroplasts. These organelles contain their own DNA, which is inherited maternally (in the case of mitochondria) and is crucial for the organelles' functions. Therefore, the correct answer is that DNA is localized in the nucleus, mitochondria, and chloroplasts.
A DNA stand is directly involved in the synthesis of all the following except –




A DNA strand is directly involved in the synthesis of another DNA strand through the process of replication, t-RNA through transcription, and m-RNA also through transcription. However, proteins are synthesized through translation, which involves m-RNA, t-RNA, and ribosomes, not directly by the DNA strand.
Nucleic acids were discovered by whom?




Nucleic acids were first discovered by Friedrich Miescher in 1869. He isolated a new substance from the nuclei of white blood cells, which he called 'nuclein,' later known as nucleic acids.
Nucleic acids are related with which activity?




Nucleic acids, such as DNA and RNA, are involved in heredity. They carry genetic information that is passed from one generation to the next and are responsible for the storage, replication, and expression of genetic information.
Chemically DNA differs from RNA by:




Chemically, DNA and RNA differ primarily in their sugar and nitrogenous bases. DNA contains the sugar deoxyribose and the nitrogenous base thymine, while RNA contains the sugar ribose and the nitrogenous base uracil. This makes option o1 correct.
Nucleic acids are polymers of which molecules?




Nucleic acids are polymers made up of nucleotide monomers. Each nucleotide consists of a sugar, a phosphate group, and a nitrogenous base. Therefore, option o2 is correct.