Analysis of Genotype Differences and the Ability to Taste PTC

THE VICTORIA SCHOOL
SANTIAGO JACOME
LAB REPORT PTC
BIOLOGY SL

AIM:
The aim of this lab is to analyze the genotype differences of classmates that are able to taste PTC, Thiourea and Sodium benzoate and determine the phenotypes found.
Testing the ability to taste PTC has been a mainstay activity in human genetics for generations of teacher and students. The ability to taste PTC is inherited. Traditionally this is presented as a case of simple Mendelian inheritance involving a dominant allele for tasting and a recessive allele for non tasting of PTC. However it has long been recognized that PTC tasting is not a trait.
Data Collection
Tastes
Student
Control
1
Neutral
2
Neutral
3
Neutral
4
Neutral
5
Neutral
6
Neutral
7
Neutral
8
Neutral
9
Sweet
10
Neutral

Student
PTC
1
Bitter
2
Bitter
3
Bitter
4
Bitter
5
Bitter
6
Neutral
7
Bitter
8
Neutral
9
Salt
10
Neutral

Student
Sodium Benzoate
1
Bitter
2
Sweet
3
Sweet
4
Sweet
5
Sweet
6
Sweet
7
Sweet
8
Sweet
9
Sweet
10
Salt

Student
Thiourea
1
Bitter
2
Bitter
3
Bitter
4
Bitter
5
Bitter
6
Bitter
7
Bitter
8
Bitter
9
Bitter
10
Sour

Genotypes Offspring’s Percentages
Control
Taste
Percentage
Neutral
90%
Sweet
10%

PTC
Taste
Percentage
Bitter
60%
Neutral
30%
Salt
10%

Sodium Benzoate
Taste
Percentage
Sweet
80%
Bitter
20%

Thiourea
Taste
Percentage
90%
Bitter
10%
Sour

Data Processing
Ability to taste PTC
60% Bitter
10% Salt
= 70 % can taste it
30% Neutral
= 30 % can`t taste it
Punnet Squares
Sample person 1: I
I
I
II
II
I
II
II

Sample person 2: I
I
I
II
II
I
II
II

Sample person 3: I
I
I
II
II
I
II
II

Sample person 4: I
I
I
II
II
I
II
II

Sample person 5: I
I
I
II
II
I
II
II

Sample person 6: i i i ii ii i ii ii Sample person 7: I
I
I
II
II
I
II
II
Sample person 8: i i i ii ii i ii ii Sample person 9: I i I
II
Ii i Ii ii Sample person 10: i i i ii ii i ii ii Relation between capacity to taste PTC, Thiourea and Sodium benzoate
Student
Control
PTC
Sodium Benzoate
Thiourea
1
Neutral
Bitter
Bitter