1. Unit 1: 1.5 Structure of the Genome
Higher Biology
Unit 1:
1.5 Structure of the Genome

2. Learning Intentions To be able to describe the structure of the genome
To be able to explain the functions of the different parts of the genome

3. Success Criteria I can describe the structure of the genome
I can explain the importance of the coding and non coding regions
I can explain the purpose of the coding and non coding regions

4. Genome
The genome of an organism is the genetic information stored in its DNA
The human genome is about 3 billion base pairs of DNA long
The genome is made up of coding and non coding regions
Only 2% of the genome is coding

5. Non coding regions
The non coding regions of the genome often take the form of DNA sequences that are repeated thousands of times over
The functions of many of these sequences remain unknown but some play important roles that are understood

6. Regulation of transcription
RNA polymerase is unable to initiate the transcription process on its own. It needs transcription factors. Some are activators (help start transcription) and some are repressors (prevent transcription).

7. Activators are bound to sequences of DNA called regulator sequences
Activators are bound to sequences of DNA called regulator sequences. Often these can be at some distance from the coding sequence.

8. The DNA must bend to bring the regulator and the activators bound to it in contact with other transcription factors close to the promoter.

10. Protection
Some of the non coding regions form a protective structure known as a telomere at each end of a chromosome
The telomere prevents damage to the chromosome by fraying at its ends

12. Non translated RNA
Some of the non coding regions of the genome form RNA molecules other than mRNA
tRNA and rRNA are both transcribed form non coding regions but are not translated

13. Success Criteria I can describe the structure of the genome
I can explain the importance of the coding and non coding regions
I can explain the purpose of the coding and non coding regions