What is DNA?
DNA stands for “deoxyribonucleic acid.” Too much? How about this, it’s the code that makes you who you are. Think of your DNA as a recipe or a blueprint for building you. There is a copy of your entire genome (the total of all your genetic code) inside of EVERY one of your body’s cells. The DNA is stored inside of the nucleus where it can stay protected. Without your DNA, your cells wouldn’t know what proteins to build in order to make your cells, tissues, organs, you!
Structure of DNA
DNA is made up of subunits called “nucleotides”. Each nucleotide contains a sugar backbone, a phosphate link, and an amino acid base. These amino acid bases are what create the “code” for DNA and they can be either A=Adenine, T= Thymine, C=Cytosine, or G=Guanine. The sugar in the nucleotide is a special type called “deoxyribose” which stands for the “D” in “DNA”. The phosphates link all of the nucleotides together like a chain. A single DNA molecule is composed of two nucleotide strands hooked together by their base pairs in the shape of a double helix (twisted ladder). This shape allows the DNA molecule to break apart and "unzip" in order to replicate.
DNA stands for “deoxyribonucleic acid.” Too much? How about this, it’s the code that makes you who you are. Think of your DNA as a recipe or a blueprint for building you. There is a copy of your entire genome (the total of all your genetic code) inside of EVERY one of your body’s cells. The DNA is stored inside of the nucleus where it can stay protected. Without your DNA, your cells wouldn’t know what proteins to build in order to make your cells, tissues, organs, you!
Structure of DNA
DNA is made up of subunits called “nucleotides”. Each nucleotide contains a sugar backbone, a phosphate link, and an amino acid base. These amino acid bases are what create the “code” for DNA and they can be either A=Adenine, T= Thymine, C=Cytosine, or G=Guanine. The sugar in the nucleotide is a special type called “deoxyribose” which stands for the “D” in “DNA”. The phosphates link all of the nucleotides together like a chain. A single DNA molecule is composed of two nucleotide strands hooked together by their base pairs in the shape of a double helix (twisted ladder). This shape allows the DNA molecule to break apart and "unzip" in order to replicate.
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From DNA to Proteins: The Recipe of Life
DNA instructs your cells in what proteins to build. Because your DNA is so important, it has to stay protected inside of the nucleus. The problem is that the machines which build the proteins (ribosomes) are located outside of the nucleus in the cell's cytoplasm. How does your cell get the recipe for the protein from the DNA to the ribosome? It's a two part process involving the stages of transcription and translation, and the key players are the messenger RNA, transfer RNA and Ribosome.
Stage 1: Transcription
The messenger RNA begins to make a copy of the DNA strand inside of the nucleus. This copying process is called "transcription" like transcribing a message onto paper. The RNA molecule is very similar to DNA except that the RNA is single stranded instead of double stranded, and it contains the base Uracil instead of Thymine. RNA is still contains the other bases adenine, guanine and cytosine as well, and is made up of nucleotides just like a single strand of DNA. Once the message has been "transcribed" the mRNA will travel outside of the nucleus to the cytoplasm to find a ribosome to attach to.
Stage 2: Translation
The mRNA attaches to the ribosome which serves as a sort of factory for building proteins. The transfer RNA molecules go out into the cytoplasm and bring back amino acids for the ribosome to hook into a protein according to the message. The tRNA translates the message three bases at a time, this three base sequence is called a "codon." Once the message has been translated, the ribosome will join all of the amino acids together into a protein.
DNA instructs your cells in what proteins to build. Because your DNA is so important, it has to stay protected inside of the nucleus. The problem is that the machines which build the proteins (ribosomes) are located outside of the nucleus in the cell's cytoplasm. How does your cell get the recipe for the protein from the DNA to the ribosome? It's a two part process involving the stages of transcription and translation, and the key players are the messenger RNA, transfer RNA and Ribosome.
Stage 1: Transcription
The messenger RNA begins to make a copy of the DNA strand inside of the nucleus. This copying process is called "transcription" like transcribing a message onto paper. The RNA molecule is very similar to DNA except that the RNA is single stranded instead of double stranded, and it contains the base Uracil instead of Thymine. RNA is still contains the other bases adenine, guanine and cytosine as well, and is made up of nucleotides just like a single strand of DNA. Once the message has been "transcribed" the mRNA will travel outside of the nucleus to the cytoplasm to find a ribosome to attach to.
Stage 2: Translation
The mRNA attaches to the ribosome which serves as a sort of factory for building proteins. The transfer RNA molecules go out into the cytoplasm and bring back amino acids for the ribosome to hook into a protein according to the message. The tRNA translates the message three bases at a time, this three base sequence is called a "codon." Once the message has been translated, the ribosome will join all of the amino acids together into a protein.