3.3 genetic code

How is DNA organised into chromosomes?

DNA is wrapped around histones to form a DNA-histone complex, which then coils further to form a chromosome.

What is a gene?

A gene is a short section of DNA that codes for a polypeptide.

What is a locus?

A locus is a specific position along a chromosome where a gene is located.

What is the genetic code?

The genetic code is the sequence of bases that code foramino acids.

What is a triplet?

A triplet is a sequence of 3 DNA bases that code for a single amino acid.

Why is the genetic code universal?

The genetic code is universal because each DNA triplet codes for the same amino acid in all organisms (with a few exceptions).

Why is the genetic code described as being non-overlapping?

The genetic code is described as being non-overlapping because each base in the DNA sequence is only read once.

Why is the genetic code degenerate?

The genetic code is degenerate because most amino acids are coded for by more than one triplet.