Here's a breakdown of the makeup of genes:
* Nucleotides: DNA is composed of building blocks called nucleotides. Each nucleotide has three parts:
* Deoxyribose sugar: A five-carbon sugar molecule.
* Phosphate group: A molecule containing phosphorus.
* Nitrogenous base: One of four different nitrogen-containing molecules:
* Adenine (A)
* Thymine (T)
* Guanine (G)
* Cytosine (C)
* Double Helix: DNA exists as a double helix, two strands of nucleotides twisted around each other like a spiral staircase. The two strands are held together by hydrogen bonds between the nitrogenous bases.
* Base Pairing: The nitrogenous bases on opposite strands of DNA always pair up in a specific way:
* Adenine (A) pairs with Thymine (T)
* Guanine (G) pairs with Cytosine (C)
* Gene Sequence: A gene is a specific sequence of nucleotides along a DNA strand. The order of these bases determines the instructions for making a particular protein.
* Protein Synthesis: The information encoded in a gene is used to create proteins through a process called protein synthesis. This process involves two steps:
* Transcription: The DNA sequence of a gene is copied into a messenger RNA (mRNA) molecule.
* Translation: The mRNA molecule is used as a template to build a protein.
In summary: Genes are segments of DNA that contain the code for building and maintaining an organism. They are composed of nucleotides, which are arranged in a specific order to create unique sequences. This information is translated into proteins that perform various functions within the body.
