UNIT 11: Genetics and Genetic Engineering
Learning Aim C: Explore the principles of inheritance and their application in predicting
genetic traits:
C.P4: Carry out investigations to collect and record data for mono and dihybrid phenotypic
ratios.
C.P5: Explain genetic crosses between non-affected, affected and carriers of genetic
conditions.
C.M4: Analyse data to explain the correlation between observed pattern of monohybrid
and dihybrid inheritance.
C.M5: Apply Mendel’s laws of inheritance to the results of genetic crosses.
C.D3: Make valid predictions on patterns of monohybrid and dihybrid inheritance and
variation using principles of inheritance.
C.P4: Carry out investigations to collect and record data for mono and dihybrid phenotypic
ratios.
Monohybrid inheritance:
Monohybrid inheritance is a type of inheritance which is
involved with only one gene in order to pass it to the next
generation. This can be determined using a Punnett Square. A
Punnett Square shows the probability of combinations of alleles
that an offspring can have.
Monohybrid crosses:
In a monohybrid cross there are two types of alleles. The
dominant allele is usually represented by a capital letter, whilst
the reccessive allele is represented by a lowercase letter. A
dominant allele is able to express its genotype withiout the
presence of the recessive allele. A recessive allele is not able to Kennisgeving voor omleiding (no date). Available at:
https://www.google.com/url?sa=i.
express its genotype when the dominant alle is present. All the
alleles in this type of cross are heterozygous (different alleles)
for a particular gene. Monohybrid crosses can be represented like this: Y-black and y-silver. To find
out all the possible probabilities of the phenotypes that an offspring can have, we need to list all the
genotypes and then calculate the phenotypic and genopyic ratios. In this instance, the monohybrid
cross is used to express the colour of different buttons: black and silver. The black colour button is
dominant so it should be expressed as (Y). The silver colour button is recessive so it should be
expressed as (y).
A punnet square for the monohybrid cross:
Gamete Y y
Y YY Yy
y Yy yy
Learning Aim C: Explore the principles of inheritance and their application in predicting
genetic traits:
C.P4: Carry out investigations to collect and record data for mono and dihybrid phenotypic
ratios.
C.P5: Explain genetic crosses between non-affected, affected and carriers of genetic
conditions.
C.M4: Analyse data to explain the correlation between observed pattern of monohybrid
and dihybrid inheritance.
C.M5: Apply Mendel’s laws of inheritance to the results of genetic crosses.
C.D3: Make valid predictions on patterns of monohybrid and dihybrid inheritance and
variation using principles of inheritance.
C.P4: Carry out investigations to collect and record data for mono and dihybrid phenotypic
ratios.
Monohybrid inheritance:
Monohybrid inheritance is a type of inheritance which is
involved with only one gene in order to pass it to the next
generation. This can be determined using a Punnett Square. A
Punnett Square shows the probability of combinations of alleles
that an offspring can have.
Monohybrid crosses:
In a monohybrid cross there are two types of alleles. The
dominant allele is usually represented by a capital letter, whilst
the reccessive allele is represented by a lowercase letter. A
dominant allele is able to express its genotype withiout the
presence of the recessive allele. A recessive allele is not able to Kennisgeving voor omleiding (no date). Available at:
https://www.google.com/url?sa=i.
express its genotype when the dominant alle is present. All the
alleles in this type of cross are heterozygous (different alleles)
for a particular gene. Monohybrid crosses can be represented like this: Y-black and y-silver. To find
out all the possible probabilities of the phenotypes that an offspring can have, we need to list all the
genotypes and then calculate the phenotypic and genopyic ratios. In this instance, the monohybrid
cross is used to express the colour of different buttons: black and silver. The black colour button is
dominant so it should be expressed as (Y). The silver colour button is recessive so it should be
expressed as (y).
A punnet square for the monohybrid cross:
Gamete Y y
Y YY Yy
y Yy yy
