Sexual reproduction – kittens and variation
Student Activity Sheet – Activity 1
Two similar looking cats have bred together. We want you to help us find out what their kittens might
look like.
1. Use a suitable method to randomly generate the genotype.
Allele card strips
In the pots there are little strips of paper. These represent the parents’ genetic code. You are going to
pick out one of strip of each colour from each pot. You must not look at the code as you pick. The pots
are labelled with each feature. You will find an allele letter on each strip.
NOTE
When recording your result remember, you must keep the case the same as on the card e.g. if it is a
UPPERCASE letter keep it a capital. If you have a UPPERCASE and lowercase letter then you should
put the UPPERCASE letter first (e.g. Ff not fF).
Spinning a coin
Heads are dominant and tails are recessive. You will need to spin the coin twice for each category to
identify the allele inherited from each parent. For example, if you are doing the cat’s tail length and you
turn up a head and a tail it will be Tt, two heads is TT and two tails is tt.
Roll a die
Evens are dominant and odds are recessive. You will need to roll the die twice for each category to
identify the allele inherited from each parent. For example, if you are doing the cat’s tail length and you
turn up a 6 and a 3 it will be Tt, a 6 and 2 is TT and a 3 and 1 is tt.
2.
Using the table - record the alleles and phenotype for your kitten.
3.
Make your kitten - using the template draw in the features of your cat. Use the examples of the
parents to help you. Most features of the cat are included on the template.
4.
Compare your kitten to the parental cats, underline the differences between your kittens and their
parents on the record sheet.
Version 1
5.
Compare the variety of kittens within the class.
6.
Write down your code carefully in the boxes below.
7.
Your code will look something like this: TT, nn, Bb, EE, GG, Ll, Ff, pp.
This is your kitten’s genotype:
Version 1
Female cat
Female Cat
Male Cat
Male cat
Tt
Long tail
Tt
Long tail
Nn
Big nose
Nn
Big nose
Bb
Black nose
Bb
Black nose
Ee
Normal ears
Ee
Normal ears
Gg
Green eyes
Gg
Green eyes
Ll
Long whiskers
Ll
Long whiskers
Ff
Grey fur
Ff
Grey fur
Pp
Stripy legs
Pp
Stripy legs
Tt
Long tail
Tt
Long tail
Record table
Circle the kittens genotype and phenotype. Underline the difference between your
kitten and their parents.
Version 1
TT or Tt
Long tail
tt
Short tail
NN or Nn
Big nose
nn
Little nose
BB or Bb
Black nose
bb
Pink nose
EE or Ee
Normal ears
ee
Big ears
GG or Gg
Green eyes
gg
Blue eyes
LL or Ll
Long whiskers
ll
Short whiskers
FF or Ff
Grey fur
ff
Stripy fur
PP or Pp
Stripy legs
pp
Plain legs