Prokaryotic Translation (Protein Synthesis)

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RNA and DNA are two types of nucleic acids that store and transmit genetic information in living cells. They are composed of nucleotides, which are the building blocks of these molecules. Nucleotides have three parts: a nitrogenous base, a pentose sugar and a phosphate group.

The nitrogenous bases in RNA are adenine (A), guanine (G), cytosine (C) and uracil (U), while in DNA they are adenine (A), guanine (G), cytosine (C) and thymine (T). The pentose sugar in RNA is ribose, while in DNA it is deoxyribose. The phosphate group links the sugar of one nucleotide to the sugar of the next nucleotide, forming a backbone for the nucleic acid strand.

RNA and DNA differ in their structure and function. RNA is usually single-stranded, meaning it has only one nucleotide chain, while DNA is usually double-stranded, meaning it has two complementary nucleotide chains that form a double helix. RNA can fold into various shapes and forms, while DNA has a more rigid and stable structure.

RNA and DNA also have different roles in protein synthesis. RNA is involved in both transcription and translation, while DNA is only involved in transcription. Transcription is the process of copying a segment of DNA into a complementary strand of RNA, called messenger RNA (mRNA). Translation is the process of decoding the mRNA into a sequence of amino acids, which are the building blocks of proteins.

RNA has several types that perform different functions in protein synthesis. mRNA carries the genetic code from DNA to the ribosomes, where translation occurs. Transfer RNA (tRNA) brings the specific amino acids to the ribosomes according to the codons on the mRNA. Ribosomal RNA (rRNA) forms part of the ribosomes and catalyzes the formation of peptide bonds between amino acids. Other types of RNA, such as small nuclear RNA (snRNA) and microRNA (miRNA), are involved in regulating gene expression and processing mRNA.

DNA is the main repository of genetic information in most living organisms. It contains the instructions for making all the proteins that are essential for life. DNA is organized into units called genes, which code for specific proteins or traits. Each gene has a promoter region, which signals where transcription should start, and a terminator region, which signals where transcription should end. Between these regions, there are exons, which are the coding sequences that will be translated into proteins, and introns, which are the non-coding sequences that will be removed from mRNA.

DNA is replicated before cell division to ensure that each daughter cell receives an identical copy of genetic material. The process of DNA replication involves unwinding the double helix, breaking the hydrogen bonds between the complementary bases, and using each strand as a template for synthesizing a new complementary strand. The enzyme DNA polymerase catalyzes this reaction by adding nucleotides to the 3` end of the growing strand. The result is two identical copies of DNA, each consisting of one original strand and one new strand.

In summary, RNA and DNA are two types of nucleic acids that store and transmit genetic information in living cells. They differ in their structure and function, but they work together to enable protein synthesis. RNA is involved in both transcription and translation, while DNA is only involved in transcription. RNA has several types that perform different functions in protein synthesis, while DNA is organized into units called genes that code for specific proteins or traits. DNA is replicated before cell division to ensure that each daughter cell receives an identical copy of genetic material.