Introduction to Genetics

Emma Cordes


Genotype: the genetic combination of an individual organism. (ex. TT, Tt, tt)

Phenotype: the physical appearance or trait (ex. tall, short, round, red)

Homozygous: the two alleles for a trait are the same. (ex. HH, hh)

Heterozygous: the two alleles for a trait are different. (Yy, Hh, Tt)

Dominant: the allele that masks or hides the recessive allele (uppercase).

Recessive: the allele that is masked or hidden by the dominant allele (lowercase).


How can someone predict the traits of offspring?

One of the easiest ways to predict the specific traits of offspring is the Punnet Square. The Punnet Square allows us to find all the potential combinations of genotypes that may occur in the offspring, given the genotypes of their parents.


Why is it important to study the principles of inheritance?

Studying the way traits are passed on to offspring is far more important than most would assume. Over the years, scientists are constantly finding ways to prevent and correct genetic disorders through this ongoing research. Without it, occurrences of birth defects and illnesses in the offspring of both human and animals would be dangerously common.