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Gene Jury
Single Gene Cross
Cell
DNA
Living thing!
Wee baldy sheep
Nucleus
Chromosomes
size
gene
(wee)
DNA
Genes
Every animal has two sets of genes,
One from its mum and one from its dad
Genes from dad
Genes from mum
size
size
gene
gene
What will the sheep look like?
Size gene: big = dominant
A
B
Lambing season
You and your partner are going to be two sheep parents, making a
lamb together.
EachEach
choose
one size
gene card
– this amakes
a gamete.
parent
has genes
and needs
card pack.
All animals
two
of the
eachgamete
gene, one
mum and
Make have
a lamb
byversions
combining
withfrom
yourtheir
partner’s
one from their dad. We will look at size genes today.
Turn over the cards to see which gene characteristics
(allelles)
your
lambfrom
will carry
Each remove the two
size gene
cards
the pack and place them
Record your lamb’s
gene
characteristics
on your sheet
coloured
side
up on the table.
Leave the other cards in the pack.
Your
gamete
LAMB
Partner’s
gamete
Now take your own cards back.
Repeat the lambing process to make a
second lamb
.
What did your lambs look like?
Lets work out the ratio of different lambs.
In your pairs:
one of you vote for lamb 1
the other vote for lamb 2.
A
B