Heredity, Punnett Squares, and Genetic Inheritance in Biology

This assignment delves into the principles of heredity and the use of Punnett Squares to predict genetic outcomes. It explains the concept of Punnett Squares as a graphical method to determine the probability of a cross or breeding experiment, highlighting the role of alleles and their dominant or recessive nature. The assignment further explains dominant/recessive inheritance, X-linked inheritance, and codominant inheritance of genes, providing a comprehensive overview of various inheritance patterns. Through this, the assignment clarifies how specific genes and their interactions influence the traits of offspring. The assignment is designed to provide a comprehensive understanding of the fundamental concepts of genetics, including the application of Punnett Squares and the intricacies of different inheritance patterns, supported by examples.

Assignment
Lab to Determine the Outcome of Heredity

What is a Punnett Square? How can it be used to analyze possible genetic outcomes for
offspring?
Punnet square is a graphical method to calculate the probability of the outcome of a cross or
breeding experiments. The method was invented by Reginald Punnet, that’s why it is called
Punnet square. Its outcome are analysed by the fact that everyone has two copies of a gene
called as allele and it can be dominant or recessive. Researchers use letter to annotate genes
suppose we talk of freckles, so here we put F as dominant while f is recessive. So if a father
has F and F (FF) father will have freckles, while mother has f and f, so there will be no
freckles on mother.
f f
F
F
After seeing a cross in punnet square it seems that all children will have freckles.
What is dominant/recessive inheritance?
Dominant or recessive inheritance is the inheritance pattern of certain traits and they describe
how likely they are going pass to next generation. So, the dominant allele is the cause of
dominant phenotype in the individual while recessive allele produces recessive one. The one
with one dominant and one recessive will have dominant phenotype and remain to be just
carrier for recessive traits.
FfFf
FfFf

What is X-linked inheritance?
X-linked inheritance is a pattern of inheritance wherein a gene in X chromosome is mutated
the traits are passed on to males who are hemizygous for the gene mutation and have only
one X chromosome and one Y chromosome. These mutations are generally recessive and
women have other copy of X chromosome so she remains a carrier and do not express the
phenotype.
What is codominant inheritance of genes?
A codominant inheritance of genes is the inheritance where two different alleles are
expressed and each make different protein. Both the genes decide genetic trait and phenotype
of the individual. Such kind of inheritance is seen in ABO blood group.