DNA is made up of genes or genes are made up of DNA?

2 Answers
Oct 4, 2015

Chromosomes are composed of DNA and the protein histone. DNA is made of nucleotides. Genes are made up of unique segments of DNA.


A gene is a segment of DNA that codes for a particular polypeptide or protein. The genes are located on the chromosomes and determine all of our hereditary traits. Humans have approximately 20000 genes. Only about 1-1.5% of the human genome contains protein-coding sequences of DNA, which are the genes. Scientists are studying the purpose of the rest of the 99% of the DNA.

The diagram below shows the structure of a chromosome.

In the diagram below you can see that a gene is a sequence of DNA that codes for a protein. Therefore, the gene is made of DNA.http://igbiologyy.blogspot.com/2014/03/chromosomes-dna-genes-and-alleles.html

The diagram below shows that genes are located at specific places on the chromosomes called loci (singular: locus). The different forms of the same gene are called alleles, and they are at the same locus on the homologous chromosomes.

Oct 12, 2015

Both of the sentences are correct, it is just a matter of interpretation.


DNA stands for Deoxyribonucleic Acid , in opposition to Ribonucleic acid, for RNA, or amino acids, for proteins.

DNA is made up of genes or genes are made up of DNA?

Both of the sentence can be found on the literature. It is likely due to the fact that the genetic code was discovered step by step, DNA is used to designate "how far you want to go". See: http://www.researchgate.net/publication/281836484_On_the_Applicability_of_Computational_Intelligence_in_Transcription_Network_Modelling. This work may be advanced, just follow the references, or look for something more basic.

In general people also use genome to designate all the genetic code, including DNA.

You can find the sentences: "gene is composed of strands of DNA", or "the human DNA is composed of a precise number of chromosomes". In the former you are talking about DNA as the small pieces of the genome, whereas in the former, you are designating the three-dimensional-double-strands.

If you are still confused, use DNA as something abstract, see the context and guess. For instance, one can say " the primary structure of DNA", in this case you are talking about the DNA as a double-helix; "spiderman suffered a DNA overlapping", here we are talking about DNA as the pieces.

The definition of gene as well is abstract, do not fall into the trap that gene is just a sequential amount of bases, you can have gene inside gene.

Indeed, DNA is made of DNA if you interpret all you read in the literature; remember that biology is not a mathematical science!


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