When a person looks like their parents, it is because of genes that are passed down from the parents to the children. The study of this is called Genetics.

Genetics works with DNA and chromosomes to help us to get our looks and many of our traits.

What Are Genetics Made Of?

Genetics are made up of all kinds of different features and these features help to determine what a person will look like.

A person will have traits that are passed down to them from their parents. The traits are the different characteristics that the organism has.

A person is not the only organism to have genetics. Genetics works in any living organism.


A different form of gene is called an allele. An allele is made up of chromosomes and DNA. Each person will get one allele from their mom and one allele from their dad.

When studying genetics, we learn how the different alleles give us different characteristics.

Dominate and Recessive Genes

Genetics deals with dominate and recessive genes. When a gene is dominate, it means that it basically rules over the other allele and it is always going to be seen.

When a gene is recessive, it means that it is basically hidden by the other allele and it will not be seen unless both parents have recessive genes.

Capital letters are used to represent dominate genes and lowercase letters are used to represent recessive genes.

Genotype and Phenotype

A genotype is when an organism has alleles that determine the phenotype or what the organism will look like.

Homozygous and Heterozygous

When a person has two alleles that were gotten from their mom and dad, it is called homozygous.

When a person has two different alleles that were gotten from their mom and dad, it is called heterozygous.

An example of this is tongue rolling. The allele for tongue rolling is R. This means that tongue rolling is a dominate feature. If someone cannot roll their tongue, that is recessive and that is r.

If your mom is homozygous, that means that her genotype is RR and she can roll her tongue.

If your dad is heterozygous for tongue rolling, that means his genotype is Rr. This means that your dad can roll his tongue because the he has the dominate gene R for being able to roll his tongue.

Even though he has a dominate and a recessive gene, the dominate gene wins out and he can roll his tongue.

Facts About Genetics

  • Hybrids is another name for heterozygous.
  • Another name for homozygous is purebred.
  • In order to find out probability of a gene, you could use a Punnett Square. A Punnett Square takes both parents genes and decides what percent would make the gene recessive or dominate.
  • Having a detached earlobe is a dominate trait.
  • Having an attached earlobe is a recessive trait.
  • Punnett Squares help to show different ways that alleles can combine.
  • Alleles for blue eyes is recessive.
  • Alleles for brown eyes is dominate.

What Did You Learn?

  • What is the study of genetics? The study of genetics is finding out what traits are passed down from parent to the offspring.
  • What is another name for heterozygous? Another name for heterozygous is hybrids.
  • What is an allele? An allele is a different form of a gene.
  • Who do you get your genes or your alleles from? A person gets their genes or their alleles from each parent. Each parent gives one allele to their offspring.
  • Dominate and recessive traits are important, why? Dominate and recessive traits help to determine what a person, plant, animal or living thing will look like.