Could two individuals with type O every produce offspring with type A?

mendel's first law states that during the formation of reproductive cells , pairs of hereditary factors for a specific trait separate so that offspring receive one factor from each parent.

explanation:

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products

if you know your abc's you should be able to get your answer or just use google