Download Gene Scene - Young Engineers and Science Clubs Scotland

Gene Scene
A pack of 5 topics exploring the world of Genetics,
aimed at S1-S3 pupils
Gene Scene
Contents
Contents
Overview of Information Pack ................................................................................................. 3
Topic 1: Inheritance ................................................................................................................ 4
Activity 1: Nature or Nurture? .............................................................................................. 4
Activity 2: Traits ................................................................................................................... 6
Topic 2: What are genes made of? ......................................................................................... 9
Activity 1: DNA Codes ......................................................................................................... 9
DNA Code Grids ................................................................................................................ 11
DNA Information Sheet ...................................................................................................... 12
Activity 2: DNA Model ........................................................................................................ 13
Activity 3: DNA Isolation from Fruit and Vegetables .......................................................... 14
Topic 3: Breaking the Code : Teacher’s Notes ..................................................................... 16
Activity 1: RNA Transcription Jigsaw ................................................................................. 16
Activity 2: Breaking the Code Translating the Code ......................................................... 23
Topic 4: Proteins : Teacher’s Notes ...................................................................................... 25
Activity 1: Protein Match .................................................................................................... 25
Topic 4: Proteins – Protein Match : Pupil Worksheet ......................................................... 26
Activity 2: What’s in a Name? ............................................................................................ 27
Topic 5: Genetic Predictions……………………………………………………………………… 29
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Gene Scene
Overview
Overview of Information Pack
This information pack contains an overview of each of the 5 topics along with teacher’s
notes, background information, details of how to set up the activities and Pupil worksheets
where appropriate.
Genetics is the study of the genome, which is a complete set of an organism’s genes. This
is important as human genetics give information about people’s traits.
The information pack introduces the topic of inherited traits before looking at some of the
science behind this. Genes themselves are small pieces of DNA. Therefore, the resource
also has activities looking at DNA and how it can code for mRNA, which in turn codes for
functional proteins.
It is proposed that this information pack contains enough material for at least 6 weeks
work. It is aimed at S1-S3 pupils. For some of the topics, there are a number of activities
that, depending on the duration of the club, may all be able to be carried out in the same
week, but could be split over different sessions.
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Gene Scene
Topic 1: Inheritance
Teacher’s Notes
Topic 1: Inheritance
Overview:
This topic is used to introduce the pupils to inherited traits.
Every attempt has been made to generalise the information in as far as possible, to avoid
any issues due to family circumstances, but this topic requires some sensitivity to pupils’
circumstances.
There are two activities in this topic:
1. Nature or nurture?
2. Traits
Activity 1: Nature or Nurture?
Aims:
To introduce different traits
Materials:
Tape measures may be helpful
Enough clear space for the pupils to get into groups or a line
Paper and pens for recording results
Sort each person in the class into groups or a line by the following characteristics:
1. Male/female
2. Eye colour
3. Dimples
4. Hair colour
5. Height
6. Shoe size
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Gene Scene
Topic 1: Inheritance
Teacher’s Notes
Suggested questions to ask the pupils [and expected results]:

What characteristics were easy to determine your grouping? [Those with clear cut
categories and those that were easily observable.]

What groups were you in?
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Which characteristics have definite options? [Male/female, eye colour, hair colour,
dimples – These are called discrete variables as there are definite categories.]
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What characteristics have a ranked line order? [Height, shoe size – These are
continuous categories that have a large range.]
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Where did you come in the line?

What characteristics can be affected by environmental conditions? [Height and shoe
size – quality and quantity of food affect growth too. Eye colour – could have coloured
lenses. Hair colour – could be dyed.]
These observable characteristics are called traits. Some traits are passed down from
parent to child or affected by the environmental conditions.
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Gene Scene
Topic 1: Inheritance
Teacher’s Notes
Activity 2: Traits
Traits are the observable characteristics that people exhibit. They can be inherited, learnt
or affected by the environment.
Aims:
To investigate how common different traits are within a population group.
Safety:
In the past, the PTC taste test has also been used to test for genetic traits.
However, there is concern about the safety and so it is advised that the PTC
test should not be carried out.
Materials:
Pen
Small sticky notes – two colours
Large sheets of paper with one of the following headings: tongue rolling and
ear lobe attachment. Below each heading, draw a line halving the paper and
put yes in one half and no in the other.
Mirrors (optional)
Large piece of paper with the diagram shown in Figure 1
Part 1:
1. Give each boy one colour of post-it notes and the girls the other colour. Each pupil will
need two post-it notes.
2. Ask the pupils if they can roll their tongue lengthways. They may wish to have access to
a mirror to check. The pupils should put one post-it note in the yes or no column
depending on their answer.
3. Ask the pupils if the bottom of their ear lobes attached right to the very bottom of the ear
lobe, or are they detached at the bottom. Again the pupils should put one post-it note in
the yes or no column depending on their answer.
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Gene Scene
Topic 1: Inheritance
Teacher’s Notes
Suggested questions to ask the pupils [and expected results]:

How many are in the class?

How many people can roll their tongue? What percentage is this?

How many people cannot roll their tongue? What percentage is this?

What percentage of the people who can roll their tongue are male?

What percentage of the people who can roll their tongue are female?

How many people have attached earlobes?

What percentage of males have attached earlobes?

What percentage of females have detached earlobes??
There are lots of different traits. In a population, some traits are more common than
others.
Part 2:
1. Give each boy one colour of post-it notes and the girls the other colour. Each pupil will
need four post-it notes.
2. Everyone should put one post it note next to class.
3. They should then add a post it note to each trait that applies to them, following the lines.
(e.g. going along the top, the first is class, then males, then males who have their
earlobe attached, then males who have their earlobe attached and who can roll their
tongue).
Suggested questions to ask the pupils [and expected results]:

Can you see how there are common traits in the group?

Do you notice anything about the groups as you move from left to right? [Less people as
the groups get more specific.]

Which group has the most people and therefore is the most common grouping of traits?

Which group has the least people and therefore is the least common grouping of traits?
Every person will have a slightly different combination of all the possible traits.
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Gene Scene
Topic 1: Inheritance
Teacher’s Notes
Can roll tongue
Ear lobe attached
Cannot roll tongue
Male
Can roll tongue
Ear lobe detached
Cannot roll tongue
Class
Can roll tongue
Ear lobe attached
Cannot roll tongue
Female
Can roll tongue
Ear lobe detached
Cannot roll tongue
Figure 1: Diagram for Traits Activity (part 2)
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Gene Scene
Topic 2: What are genes made of?
Teacher’s Notes
Topic 2: What are genes made of?
Overview:
Genetics is the science of how traits are passed from one generation to another via genes.
Genes are parts of DNA molecules. The DNA is contained in chromosomes in the nucleus
of cells. Each person has 46 chromosomes – 23 from your mother and 23 from your father.
There are lots of different combinations.
Every person has a different genetic makeup.
This topic uses two activities to illustrate the DNA structure:
1. DNA codes – this introduces the building blocks of DNA and how they join together
2. DNA model – this uses sweets and cocktail stick to model the DNA helix structure.
There is then a third activity to isolate plant DNA.
Extension:
Make a DNA origami model from http://www.yourgenome.org/teachers/origami.shtml
Activity 1: DNA Codes
Aims:
To introduce the students to the DNA code
Materials:
DNA Information Sheets (see page 13)
DNA Code Sheets (see below and page 11)
Pens
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Figure 2: DNA Code Grid
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Gene Scene
Topic 2: What are genes made of?
Teacher’s Notes
1. On the top line of the grid in the code sheet, write a random list in the blank boxes of the
following four letters: A, C, G and T. These letters, A, C, G and T represent the DNA
building blocks, called bases. The bases are bonded to each other. This is represented
by the – between the boxes.
2. DNA is made up of two chains. Fill in the bottom line according to the DNA ‘rules’:
o If there is an A in the top row, put a T in the bottom square.
o If there is a C in the top row, put a Gin the bottom square.
o If there is a G in the top row, put a C in the bottom square.
o If there is a T in the top row, put an A in the bottom square.
3. As well as being bonded to each other in the chain, the bases are also bonded to the
other chain. Join the each of the letters in the top row with the bottom row by bond
lines. Keep the code you have written as it will be used in later activities.
The order of this code gives the genetic detail. The chains are then twisted into a
shape called a double helix. This will be demonstrated in the next activity.
Suggested questions to ask the pupils [and expected results]:
Does anyone have a matching code? [Unlikely as there are so many combinations
possible.]
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Gene Scene
Topic 2: What are genes made of?
DNA Code Grids
DNA Code Grids
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Gene Scene
Topic 2: What are genes made of?
Teacher’s Notes
DNA Information Sheet
DNA stands for deoxyribonucleic acid.
DNA is contained in chromosomes in the nucleus of cells.
It is a long molecule made up of combinations of 4 different subunits called bases. These
are known by the letters A, C, G and T and are shown in Figure 3:
A, Adenine
T, Thymine
G, Guanine
C, Cytosine
Figure 3: Structures of the DNA bases
These bases are joined together in long chains via deoxyribose and phosphate.
Two chains are joined together via base pairing, where A bonds with T and G bonds with C.
These chains are twisted as shown in Figure 4. This shape is called a double helix.
Figure 4: DNA double helix structure.
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Gene Scene
Topic 2: What are genes made of?
Teacher’s Notes
Activity 2: DNA Model
Aims:
To model the 3D shape of DNA
Safety:
DO NOT eat the sweets
Check for allergies
Take care when using the cocktail sticks
Materials:
DNA information sheet
Cocktail sticks
Jelly sweets in 4 different colours
The code from the previous activity
1. Read the DNA information sheet
2. As a class decide on a colour code for the bases.
3. Using the jelly sweets and the colour code, going along the top row of your code, join
the jelly sweets together using the cocktail sticks.
4. Repeat with the bottom row of the code.
5. Join the rows together so each complementary base pair is “bonded” using the cocktail
sticks.
6. Once you have completed this, it will look like a ladder. To make this into a double
helix, lift the model at both ends and twist. This twisted model (as shown in Figure 5)
illustrates the double helix structure of DNA.
Figure 5: DNA model
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Gene Scene
Topic 2: What are genes made of?
Teacher’s Notes
Activity 3: DNA Isolation from Fruit and Vegetables
Aims:
To isolate a DNA sample from fruit and vegetables
Safety:
Do not eat the fruit and vegetables
Take care the water temperature is not too hot
Care should be taken when using the blender – it is best that the teacher
blends the fruit and then portions this.
A risk assessment and COSHH form should be completed for using ethanol
and all necessary precautions taken.
Materials:
Cold water
Ice
Salt
Washing up detergent
Warm water
Plastic bowl
100 ml and 250 ml beakers
Ethanol
Salt
Balance or teaspoon
Measuring cylinder
Blender
Fruit, e.g. banana, strawberries, onions
Sieve
Filter paper
Stirring rod
Boiling tube
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Gene Scene
Topic 2: What are genes made of?
Teacher’s Notes
Method:
1. Place ice and some cold water in the plastic bowl.
2. Pour approximately 50 ml of ethanol into a beaker and place the beaker in the ice bath
to cool the ethanol.
3. Dissolve approximately 5 g (or add a small teaspoonful) of salt and 10 ml (or two
teaspoonfuls) of detergent in 150 ml warm water.
4. Blend the fruit (approximately 50 g per experiment)
5. Add the warm water, salt and detergent mix to the blended fruit, then mix.
6. Put the filter paper in the sieve and sieve the mixture into the beaker. The pupils will
need to mix with care, taking care not to rip the filter paper.
7. Transfer about 5 ml of filtrate to the boiling tube.
8. Carefully add 5-10 ml of the cold ethanol down the side of the boiling tube on top of the
filtrate.
9. Let the solution sit for about 2 minutes without disturbing the layers.
10. Look at where the ethanol meets the water mixture and you will see some white strands.
This is the DNA from the fruit. Point out that it doesn’t look like the twisted structure
from the earlier activity as it is very small and you cannot see one individual strand.
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Gene Scene
Topic 3: Breaking the Code
Teacher’s Notes
Topic 3: Breaking the Code : Teacher’s Notes
Overview:
The DNA letters are the DNA code. The order of the DNA bases A, C, G and T gives the
DNA code. It is used for making proteins, but it doesn’t do this directly. The DNA code can
determine the structure of proteins. To do this, there is a two-step process. First the DNA
code is transcribed to a RNA code. This RNA code is then translated into a sequence of
amino acids which are joined together to form the protein.
This topic uses two activities to illustrate how DNA codes for proteins via mRNA:
1. RNA Transcription Jigsaw
2. Translating the Code
Activity 1: RNA Transcription Jigsaw
Aims:
To transcribe the DNA code to an RNA code.
Materials:
Jigsaw pieces - each sheet of jigsaw pieces should be copied on different
colours of paper so each base has a different colour – see p20-24.
Scissors – ask the pupils to cut out the jigsaw pieces
The code from the previous activities
1. After cutting out the jigsaw pieces, put them in a pile to mix them up. The pupils should
use the A, C, G and T jigsaw pieces to make the DNA code written earlier. You should
have two linked chains.
The DNA code is then transcribed into another code called a RNA code. RNA stands
for ribonucleic acid. The RNA is only a single strand and is made up of A, C, G and U
(Uracil). This time A bonds with U.
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Gene Scene
Topic 3: Breaking the Code
Teacher’s Notes
2. Separate the two DNA chains from each other and then use the RNA jigsaw pieces to
form the RNA code.
3. Write down the RNA sequence and keep a copy of this for the next activity
The RNA code is then translated into a protein.
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Gene Scene
Topic 3: Breaking the Code
Teacher’s Notes
A
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Gene Scene
Topic 3: Breaking the Code
Teacher’s Notes
T
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Gene Scene
Topic 3: Breaking the Code
Teacher’s Notes
C
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Gene Scene
Topic 3: Breaking the Code
Teacher’s Notes
G
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Gene Scene
Topic 3: Breaking the Code
Teacher’s Notes
U
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Gene Scene
Topic 3: Breaking the Code
Teacher’s Notes
Activity 2: Breaking the Code Translating the Code
Aims:
To translate the RNA code into a protein
Materials:
The RNA code from the previous activity
The amino acid code sheet – see p26
From your DNA code, you transcribed a RNA code. To get a protein, you need to translate
the RNA code. In this activity you will translate your RNA code into amino acids. The amino
acids join together to form a protein.
1. When translating the RNA code into a protein, starting from the end, group the RNA
code into three letter groups.
2. Using the amino acid code sheet, find the amino acid that corresponds to each of the
three letter codes.
e.g. AGU is Ser or S
3. Continue until you have a list of five amino acids.
The amino acids are bonded together to form a protein. The sequence determines
the type of protein and its function.
Suggested questions to ask the pupils [and expected results]:
Has anyone got the same protein sequence? [This is very unlikely as although there are
only 4 different options for the bases, these bases can create lots of different sequences.]
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Gene Scene
Topic 3: Breaking the Code
Teacher’s Notes
Amino Acid Code Sheet
Second Letter
A
C
G
U
AAA
Lys (K)
ACA
AGA
Arg (R)
AUA
AAC
Asn (N)
ACC
AGC
Ser (S)
AUC
AAG
Lys (K)
ACG
AGG
Arg (R)
AUG
Met (M)
AAU
Asn (N)
ACU
AGU
Ser (S)
AUU
Ile (I)
CAA
Gln (Q)
CCA
CGA
CAC
His (H)
CCC
CAG
Gln (Q)
CCG
First
CAU
His (H)
CCU
CGU
CUU
Third
Letter
GAA
Glu (E)
GCA
GGA
GUA
Letter
GAC
Asp (D)
GCC
GAG
Glu (E)
GCG
GAU
Asp (D)
GCU
GGU
UAA
STOP
UCA
UGA
STOP
UUA
Leu (L)
UAC
Tyr (Y)
UCC
UGC
Cys (C)
UUC
Phe (F)
UAG
STOP
UCG
UGG
Trp (W)
UUG
Leu (L)
UAU
Tyr (Y)
UCU
UGU
Cys (C)
UUU
Phe (F)
A
C
G
U
Thr (T)
Pro (P)
Arg (R)
Ser (S)
CGC
CGG
GGC
GGG
Ile (I)
A
CUA
Arg (R)
Gly (G)
CUC
CUG
GUC
GUG
Leu (L)
Val (V)
C
G
GUU
U
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Gene Scene
Topic 4: Proteins
Teacher’s Notes
Topic 4: Proteins :
Overview:
The previous two topics have looked at DNA and how it codes for proteins. Often pupils
think of proteins as components of food. This topic introduces the wide range of proteins.
This topic uses two activities to discuss proteins:
1. Protein Match
2. What’s in a Name?
Activity 1: Protein Match
Aims:
To show some the wide variety of functions of proteins within the body
Materials:
Protein grid
Pens
Internet access will be needed for some of the examples
Table 1 shows some functions for proteins within the body. Match the names to the
descriptions – complete the table on p28.
Table 1: Answers for the protein match activity
Name
Description
Haemoglobin in blood
Transports oxygen round the body
Insulin
Involved in regulating blood sugar uptake
Myosin and actin in muscles
Involved in movement
Fibrin
Involved in wound healing
Antibodies
Defend your body against infection
Pepsin
Example of digestive enzyme
Collagen
Structural protein that supports connective
tissues, e.g. skin, ligaments and tendons.
Tubulin
Forms hollow tubes supporting cell structure
Keratin
In strands of hair and in nails
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Gene Scene
Proteins Match
Pupils Worksheet
Topic 4: Proteins – Protein Match : Pupil Worksheet
In the previous activities, you have shown how the DNA code can be translated to a protein
(via RNA). In this activity, you will try to identify some of the proteins that are found in your
body.
The following table shows some functions for proteins within the body. Match the names to
the descriptions. You may need to do some research for this activity.
Name
Description
Transports oxygen round the body
Involved in regulating blood sugar uptake
Involved in movement
Involved in wound healing
Defend your body against infection
Example of digestive enzyme
Structural protein that supports connective
tissues, e.g. skin, ligaments and tendons.
Forms hollow tubes supporting cell structure
In strands of hair and in nails
Antibodies; Collagen; Fibrin; Haemoglobin in blood; Insulin; Keratin; Myosin and actin in
muscles; Pepsin; Tubulin
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Gene Scene
Topic 4: Proteins
Teacher’s Notes
Activity 2: What’s in a Name?
Aims:
To use the concept of coding to find a DNA sequence and a protein, using the
pupils’ name as the amino acid code
Materials:
Access to internet
Paper and pens
Amino acid code table
In the previous activities you have used the DNA code to find the RNA code and then find
the protein amino acid code. The sequence of the letters can be in any order so there are
lots of possible combinations. In this activity, you will use your name as an amino acid
code and see if you can find the DNA code and then identify your name as a protein!
Part 1:
1. Write your name down.
2. Use the amino acid code table to convert your name into an RNA sequence.
E.g. if the first letter is L, then this would correspond to the amino acid leucine (Leu).
From the table, the RNA code for Leu is either UUA or UUG, choose one and write this
down.
If your name has a letter that is not an amino acid then the RNA triplet should be written
as NNN. The N means that it could stand for any combination of bases.
3. Convert the RNA sequence to a DNA sequence (A becomes T, U becomes A, C
becomes G and G becomes C).
If you have used NNN in the RNA sequence then keep this as NNN for the DNA
sequence. This is the DNA code for your name.
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Gene Scene
Topic 4: Proteins
Teacher’s Notes
Part 2:
1. Find the website page http://www.ebi.ac.uk/cgi-bin/decode/decode.cgi
2. Type your name in the box and press decode. This will give you a similar DNA code
and also search the database to see if this DNA code corresponds to any known
proteins that are found in any genomes that have been sequenced to date.

Which genome contains YOUR protein?
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Gene Scene
Topic 5: Genetic Predictions
Teacher’s Notes
Topic 5: Genetic Predictions
Overview:
Since people’s traits can be inherited, knowing the full genotypes of the parents allows you
to make predictions for the probability of the offspring exhibiting certain traits and
characteristics.
This topic uses three different examples to illustrate how this can be achieved using the
Punnett Square method:
1.
Boy or Girl?
2.
Dominant vs Recessive
3.
Eye Colour
4.
Blood Types
Aims: To predict the probability of a number of characteristics using a tool called a Punnett
Square.
Materials:
Pen
Copies of the Punnett square sheets (pupils’ worksheet)
Example 1: Boy or Girl?
In their genetic material, females have XX chromosomes, while males have XY
chromosomes. If each parent were to give one of these chromosomes to their offspring,
what percentage chance would there be of them having a boy and what percentage chance
would there be of them having a girl? To find this out, we use something called a Punnett
square.
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Gene Scene
Topic 5: Genetic Predictions
Teacher’s Notes
In the grid shown in Table 2, you will see four empty boxes which you will fill in with the
children’s inherited chromosomes.
Table 2: Male or female Punnett square grid
Father: XY
Mother: XX
X
Y
X
X
The father’s XY chromosomes are at the top. The offspring can inherit either an X or a Y.
To show this on the grid, they should write an X in each of the boxes in the column below
the X. Then do the same for the Y column.
Next, the mother’s chromosomes are XX and are on the side of the grid. The offspring can
either inherit one X or the other. To show this on the grid, they should then write an X in
each of the boxes in the row next to the top X, before doing the same for the other row.
They should now have written two letters in each of the blank boxes and be able to identify
the % chance of having a boy or girl.
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Gene Scene
Topic 5: Genetic Predictions
Teacher’s Notes
The same technique can be used for other characteristics inherited from through genes.
Suggested questions to ask the pupils [and expected results]:
How many XX have they written? [2]
How many XY have they written? [2]
What does this mean? [Remember back to the start, where we said females were XX and
males were XY.]
How many of the 4 offspring would be girls? [2]
How many of the 4 offspring would be boys? [2]
What % chance would the parents have of having a girl? [2 of the 4, therefore 50% chance]
What % chance would the parents have of having a boy? [2 of the 4, therefore 50% chance]
Example 2: Dominant vs recessive
A similar process can be used for other genetic characteristics. Next, the pupils should
repeat the previous process with the Punnett square in Table 3,.
In this example, both parents have the same genetic information for this characteristic, Ee.
This is going to represent earlobe attachment with both parents having unattached
earlobes. It is written in this way because the capital E is dominant over the small e, which
is the recessive characteristic of attached earlobes. This means that if the capital E is
present then the earlobe will be unattached. The earlobe would only be attached if the
person has the genotype ee.
Table 3: Dominant or recessive Punnett square grid
Father: Aa
Mother: Aa
E
e
E
e
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Gene Scene
Topic 5: Genetic Predictions
Punnet Square Grids
Suggested questions to ask the pupils [and expected results]:
How many different combinations are there? [3, EE, Ee, ee]
How many of each type? [I EE, 2 Ee and 1 ee]
What % chance would the child have of having unattached earlobes? [75%, 3 out of the 4
have E present at least once]
What % chance would the child have of having attached earlobes? [25%, only the ee
genotype doesn’t have E present at all]
Example 3: Eye Colour
The previous example used one gene type. There are other characteristics that have two
or more genes and this makes the Punnett square bigger and the predictions more difficult
to predict. Eye colour can be simplified to two genes with them being represented by the
letter A and B. The rules:
1.
2.
3.
4.
A is for brown eyes
a is for blue eyes
A is dominant and a is recessive
B is for green eyes
5. b is for lighter eyes
6. B is dominant and b is recessive
7. A is more dominant than B.
Using a similar strategy to the previous examples, complete Table 4
Table 4: Eye colour Punnett square grid
Father: AaBb
AB
Ab
aB
ab
Mother: AaBb
AB
Ab
aB
ab
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Gene Scene
Topic 5: Genetic Predictions
Punnet Square Grids
Male or female Punnett square grid
Dominant or recessive Punnett square grid
Father: Aa
Father: XY
E
Y
X
Mother: Aa
Mother: XX
X
X
e
E
e
Eye colour Punnett square grid
Father: AaBb
AB
Ab
aB
ab
Mother: AaBb
AB
Ab
aB
ab
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Gene Scene
Topic 5: Genetic Predictions
Teacher’s Notes
Suggested questions to ask the pupils [and expected results]:
Table 5: Answers
Type
How many of each?
What colour would these give?
AABB
1
Brown
AABb
2
Brown
AAbb
1
Brown
AaBB
2
Brown
AaBb
4
Brown
Aabb
2
Brown
aaBB
1
Green
aaBb
2
Green
aabb
1
Blue

How many different types are there?

How many of each?

What colours would each type give?

Do you think all the brown eyes would be the same colour? Why? [No, some will be
darker than others due to the effect of the b gene.]

Which brown genotype do you think would be darkest? [AABB would be darkest
because of the presence of only dominant brown on one gene and no presence of
the lighter b on the other gene.]
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Gene Scene
Topic 5: Genetic Predictions
Teacher’s Notes
In practice, while this is a very good approximation for eye colour genetics, the
genetics can be more complex than this.
Example 4: Blood Types:
Everyone has one of four blood types, A, B, AB or O. The genetic information for the blood
types is shown in Table 6. Both A and B are dominant over O which is recessive.
Table 6: Blood type genotypes
Blood Type
Genotype
A
AA or AO
B
BB or BO
AB
AB
O
OO
Complete the family tree information (Figure 6) with blood type and genotype.
HINT: Look for the blood types with only one genotype and fill these in first as this should
help for the others.
Answers are shown in Figure 7
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Gene Scene
Topic 5: Genetic Predictions
Pupil Worksheet
Blood Group A
Blood Group B
Genotype AO
Genotype ___
Blood Group A
Blood Group A
Blood Group B
Blood Group AB
Blood Group O
Blood Group __
Genotype AO
Genotype ___
Genotype ___
Genotype ___
Genotype ___
Genotype ___
Blood Group A
Blood Group A
Blood Group A
Blood Group B
Genotype ___
Genotype ___
Genotype ___
Genotype ___
Figure 6: Blood type family tree
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Gene Scene
Topic 5: Genetic Predictions
Teacher’s Notes
Blood Group A
Blood Group B
Genotype AO
Genotype BO
Blood Group A
Blood Group A
Blood Group B
Blood Group AB
Blood Group O
Blood Group AB
Genotype AO
Genotype AO
Genotype BO
Genotype AB
Genotype OO
Genotype AB
Blood Group A
Blood Group A
Blood Group A
Blood Group B
Genotype AO
Genotype AO
Genotype AO
Genotype BO
or AA
or AA
Figure 7: Blood type family tree answers
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