1. Nucleotides:
* DNA is a long chain made up of smaller units called nucleotides.
* Each nucleotide consists of three parts:
* Sugar (deoxyribose): A five-carbon sugar molecule.
* Phosphate group: A molecule containing phosphorus and oxygen.
* Nitrogenous base: A molecule containing nitrogen. There are four different nitrogenous bases in DNA:
* Adenine (A)
* Guanine (G)
* Cytosine (C)
* Thymine (T)
2. The Genetic Code:
* The sequence of these four bases along the DNA molecule is what carries the genetic information.
* This sequence is like a code, and it determines the order of amino acids in proteins.
* The code is read in groups of three nucleotides, called codons.
* Each codon corresponds to a specific amino acid.
3. Protein Synthesis:
* The DNA sequence is transcribed into a messenger RNA (mRNA) molecule.
* The mRNA molecule then travels to the ribosomes, where it is translated into a protein.
* The order of codons in the mRNA determines the order of amino acids in the protein.
* Proteins perform a wide variety of functions in the body, including:
* Enzymes: Catalyze chemical reactions
* Structural components: Provide shape and support
* Hormones: Regulate bodily processes
* Antibodies: Fight infections
In Summary:
* The information in DNA is encoded in the sequence of nucleotides.
* This sequence determines the order of amino acids in proteins.
* Proteins are the workhorses of the cell, performing a wide variety of functions.
Therefore, the DNA sequence acts as a blueprint for building and maintaining an organism.
