Genetic material DNA is contained in our chromosomes. What is the most important role of these chromosomes?

1 Answer
Mar 31, 2017
  • Chromosomes have DNA, which has the recipe to make proteins. these specific proteins tell the cell what to do.
  • Humans have lot of DNA in the form of linear molecules, which are organised and protected in the form of chromosomes.
  • Chromosomes are also necessary to pass on good genes to the next generation.

Explanation:

Chromosomes are made of super-coiled DNA. DNA contains a sequence of chemical bases which form a "recipe" template, which is used to make a strand of messenger RNA (mRNA).

The mRNA is used as a code to assemble proteins. Transfer RNA (tRNA) has 3 bases and an amino acid at the top. tRNA comes to the mRNA and looks for 3 bases complimentary to its 3 bases. When it finds this, it attaches its amino acid to the one before it. The amino acids form bonds to make a protein.

These proteins are specific to your DNA and tell the cell everything that it is supposed to do or make.

A good analogy of this would be:

  • You walk into a library (the nucleus) to find the cooking book you want (DNA strand you want). Then you find the specific recipe you want (specific DNA sequence).

  • You are not allowed to borrow the book as it is a limited edition, and the library can't risk it being damaged (you can't take DNA out of the nucleus). You thus copy the recipe you need on a sheet of paper (mRNA is formed to be taken out of the nucleus, it is sort of a copy of the DNA strand)-- a process known in cell biology as transcription.

  • You edit the recipe because it had too much unnecessary sugar (RNA gets edited and non-coding DNA, or introns, are cut out ).
    You finally take the recipe and translate it into an actual cake (this is translation of the mature mRNA strand into proteins, which are necassary for cell functioning).

In conclusion, for every genome (total genes in an individual) there is a corresponding proteome (total mix of proteins in an individual) that is necessary for the cell to function. For every gene there is one or more corresponding protein (depending on how the recipe is edited). And cells can't do anything without proteins...

Additionally, the people with the best genes survive and pass on their genes to their offspring. This process is repeated in every generation which allow us to adapt to the changes in our environment: that is called natural selection , which aids in the survival of the species altogether.... however this process takes a very long time.