THE STRUCTURE OF THE GENOME
1.3 Genome: (a) The structure of the genome
From the Arrangements
(a) The structure of the genome
The genome of an organism is its hereditary information encoded in DNA.
DNA sequences that code for protein are defined as genes. A genome is made
up of genes and other DNA sequences that do not code for proteins. Most of
the eukaryotic genome consists of these non-coding sequences. Non-coding
sequences include those that regulate transcription and those that are
transcribed to RNA but are never translated. Some non-coding sequences
have no known function.
The structure of the genome memory game
Teacher’s notes
The aim is for each group to reproduce the following page exactly by working
cooperatively under the following conditions.
Divide your students into groups of three of four.
Issue each group with two pieces of A3 paper (one for a rough copy and one
for a final copy), coloured pencils (two blue, two red and two green) and a
ruler.
Have a colour printed copy of the following page on your front d esk.
Allow one person from each group to come and look at the page for exactly 1
minute then they go back to their table and start to make a rough copy.
The next person comes out to look at the page for 1 minute before going back
to their table to add to the rough copy.
This process continues until all the information has been gathered (allow 30
minutes).
Within the allocated time each group has to gather small chunks of
information and transcribe it onto a rough copy whilst at the same time
working on their final version.
UNIT 1, PART (III) GENOME (H, BIOLOGY)
© Learning and Teaching Scotland 2011
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THE STRUCTURE OF THE GENOME
As an incentive, have some small prizes eg a bag of sweets handy to award to
the winners and runners-up.
Central image
Main: Gene structure and gene expression in higher organisms
http://www.niaaa.nih.gov/Resources/GraphicsGallery/Metabolism/Pages/gene
_structure.aspx
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UNIT 1, PART (III) GENOME (H, BIOLOGY)
© Learning and Teaching Scotland 2011
THE STRUCTURE OF THE GENOME
Genes code for proteins. The genome is
made up of genes and other DNA that
does not code for proteins:
eg Gene regulatory sequences, which
control transcription, DNA, which is
transcribed into transfer RNA (tRNA) or
ribosomal RNA (rRNA), and small pieces
of RNA and DNA sequences that have no
known function.
some DNA makes RNA
some DNA makes RNA makes protein
some DNA does not appear to do anything
Coding and non-coding sequences make
up the genome.
One gene can code for many
different proteins depending on
how many exons or which exons
are spliced together.
Introns are common in
eukaryotes and the number and
length varies a lot between
species.
Proteins are mostly enzymes that
carry out the ‘instructions’ of the
gene, giving us our
characteristics. Often one
characteristic is controlled by
more than one gene so it is a
complex business.
Genes are inherited from both parents and are passed on from
one generation to the next.
UNIT 1, PART (III) GENOME (H, BIOLOGY)
© Learning and Teaching Scotland 2011
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