Comparison of DNA and RNA: table. DNA and RNA: structure

In the article brought to your attention, we propose to study and build a comparative table of DNA and RNA. First you need to say that there is a special section of biology that deals with the storage, sale and transmission of hereditary information, its name is molecular biology. It is this area that we will touch upon further.

It will be about polymers (high molecular weight organic compounds) formed from nucleotides, which are called nucleic acids. These compounds perform very important functions, one of which is the storage of information about the body. In order to compare DNA and RNA (the table will be presented at the very end of the article), you need to know that in total there are two types of nucleic acids that are involved in protein biosynthesis:

• deoxyribonucleic, which we often find in the form of an abbreviation - DNA;
• ribonucleic (or abbreviated as RNA)

Nucleic acid: what is it?

In order to compose DNA and RNA comparison table , you need to become more familiar with these polynucleotides. Let's start with a general question. Both DNA and RNA are nucleic acids. As mentioned earlier, they are formed from nucleotide residues.

These polymers can be found absolutely in any cell of the body, since it is on their shoulders that a great responsibility is entrusted, namely:

• storage;
• broadcast;
• realization of heredity.

Now very briefly highlight their basic chemical properties:

• well soluble in water;
• practically not soluble in organic solvents;
• sensitive to temperature changes;
• if the DNA molecule is isolated in any possible way from a natural source, then fragmentation during mechanical actions can be observed;
• fragmentation occurs by enzymes called nuclease.

Similarities and differences between DNA and RNA: pentoses

IN DNA and RNA comparison table it is important to note one very important similarity between them - the presence of monosaccharides in the composition. It is important to note that each nucleic acid has their individual forms. The division of nucleic acids into DNA and RNA occurs as a result of the fact that they possess various pentoses.

So, for example, in the composition of DNA we can detect deoxyribose, and in RNA - ribose. Pay attention to the fact that at the second carbon atom there is no oxygen in deoxyribose. Scientists made the following assumption - the absence of oxygen has the following meaning:

• it shortens the bonds C ₂ and C ₃ ;
• adds strength to the DNA molecule;
• creates the conditions for laying a massive molecule in the nucleus.

Comparison of nitrogen bases

So, there are five nitrogen bases in total:

• A (adenine);
• G (guanine);
• Ts (cytosine);
• T (thymine);
• U (uracil).

It is important to note that these tiny particles are the bricks of our molecules. It is in them that all the genetic information is contained, and to be more precise, in their sequence. In DNA we can meet: A, G, C and T, and in RNA - A, G, C and U.

Nitrogen bases are a large part of nucleic acids. In addition to the five listed, there are others, but this is extremely rare.

DNA structure principles

Another important feature is the presence of four levels of organization (you can see it in the picture). As it has already become clear, the primary structure is a chain of nucleotides, while the ratio of nitrogenous bases obeys certain laws.

The secondary structure is a double helix, the composition of each chain of which is specific to the species. Residues of phosphoric acid can be found outside the spiral, and nitrogenous bases are located inside.

Next comes the supercoiled structure. In addition to the plexus of two chains, they are wound on histones (for greater compactness). Histones are special proteins that are divided into five classes.

The last level is the chromosome. Imagine that the Eiffel Tower is placed in a matchbox, this is how the DNA molecule is laid on the chromosome. It is also important to note that the chromosome may consist of one chromatid or two.

Let's talk before you make up DNA and RNA comparison table about the structure RNA

Types and structural features of RNA

For comparing the similarity of DNA and RNA (table You can see in the last paragraph of the article), we will analyze the varieties of the latter:

1. First of all, tRNA (or transport) is a single-chain molecule that performs the functions of transporting amino acids and protein synthesis. Its secondary structure is the “clover leaf”, and the tertiary has been studied very little.
2. Information or matrix (mRNA) - the transfer of information from a DNA molecule to the site of protein synthesis.
3. And the last one is rRNA (ribosomal). As the name implies, it is contained in ribosomes.

What functions does DNA perform?

Comparing DNA and RNA, it is impossible to miss the question of the functions performed. In the final table, this information will be necessarily reflected.

So, without a second's doubts, we can say that all the genetic information that is able to control our every step is programmed in a small DNA molecule. These include:

• health;
• development;
• life expectancy;
• hereditary diseases;
• cardiovascular diseases, etc.

Imagine that we isolated all the DNA molecules from one cell of the human body and arranged them in a row. How long do you think the chain will be? Many will think that millimeters, but this is not so. The length of this chain will be as much as 7.5 centimeters. Incredible, but why then we can’t make out a cell without a powerful microscope? The thing is that the molecules are very strongly compressed. Remember, in the article we already talked about the size of the Eiffel Tower.

But what kind of functions do DNA perform?

1. They are carriers of genetic information.
2. Reproduce and transmit information.

What functions does RNA perform?

For more precise comparing DNA and RNA , we propose to consider the functions performed by the second. It has already been said that three types of RNA are distinguished:

• RRNA performs the function of the structural basis of the ribosome; in addition, they interact with other types of RNA in the process of protein synthesis and take part in the assembly of the polypeptide chain.
• The mRNA function is a matrix for protein biosynthesis.
• TRNAs bind amino acids and transfer them to the ribosome for protein synthesis, encode amino acids, and decode the genetic code.

Conclusions and Comparison Chart

Schoolchildren are often given the task of biology or chemistry - to compare DNA and RNA. The table in this case will be a necessary assistant. Everything that was said earlier in the article, you can see here in a concise form.

Despite the fact that our comparative characteristic was very brief, we were able to cover all aspects of the structure and functions of the compounds under consideration. This table can serve as a good cheat sheet on the exam or just a memo.