Not even millions but 3billion base pairs....wooooah!

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<div class="wp-caption alignnone" style="width: 800px"><img alt="Photo shows Dolly the sheep, which has been stuffed and placed in a glass case." height="417" src="https://data.ulearngo.com/assets/a413d0e8-7075-473f-9ab4-fb7ed0923653" width="800"/><p class="wp-caption-text">Dolly the sheep was the first large mammal to be cloned.</p></div>
<p>The three letters “DNA” have now become synonymous with crime solving, paternity testing, human identification, and genetic testing. <a href="https://app.ulearngo.com/tutorials/introducing-genetics/dna">DNA</a> can be retrieved from hair, blood, or saliva. Each person’s DNA is unique, and it is possible to detect differences between individuals within a <a data-lesson="summarizing-community-ecology" data-subject="biology" data-tutorial="population-community-ecology" href="https://app.ulearngo.com/biology/population-community-ecology/summarizing-community-ecology">species</a> on the basis of these unique features.</p>
<p>DNA analysis has many practical applications beyond forensics. In humans, DNA testing is applied to numerous uses: determining paternity, tracing genealogy, identifying pathogens, archeological research, tracing <a data-lesson="neurodegenerative-disorders" data-subject="biology" data-tutorial="nervous-system" href="https://app.ulearngo.com/biology/nervous-system/neurodegenerative-disorders">disease</a> outbreaks, and studying human migration patterns. In the medical field, DNA is used in diagnostics, new vaccine development, and <a data-lesson="cancer" data-subject="biology" data-tutorial="introducing-the-cell" href="https://app.ulearngo.com/biology/introducing-the-cell/cancer">cancer</a> therapy. It is now possible to determine predisposition to <a data-lesson="emerging-and-re-emerging-diseases" data-subject="biology" data-tutorial="prokaryotes-bacteria-archaea" href="https://app.ulearngo.com/biology/prokaryotes-bacteria-archaea/emerging-and-re-emerging-diseases">diseases</a> by looking at genes.</p>
<p>Each human cell has 23 pairs of chromosomes: one set of <a data-lesson="chromosomes" data-subject="biology" data-tutorial="cell-biology" href="https://app.ulearngo.com/biology/cell-biology/chromosomes">chromosomes</a> is inherited from the mother and the other set is inherited from the father. There is also a mitochondrial genome, inherited exclusively from the mother, which can be involved in inherited genetic disorders. On each chromosome, there are thousands of <a href="https://app.ulearngo.com/tutorials/introducing-genetics/eukaryotic-gene-regulation">genes</a> that are responsible for determining the genotype and phenotype of the individual. A gene is defined as a sequence of DNA that codes for a functional product. The human <a data-lesson="life-cycles-of-sexually-reproducing-organisms" data-subject="biology" data-tutorial="meiosis-sexual-reproduction" href="https://app.ulearngo.com/biology/meiosis-sexual-reproduction/life-cycles-of-sexually-reproducing-organisms">haploid</a> genome contains 3 billion base pairs and has between 20,000 and 25,000 functional genes.</p>
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Introduction to DNA Structure and Function

Biology studies life and living organisms. Biology can be divided into different sections that cover the morphology, physiology, anatomy, behavior, and so on of living organisms.

Biology

Discover the history and structure of DNA, learn about DNA sequencing techniques, and explore the basics of DNA replication and repair.


Introduction to DNA Structure and Function

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