Genes

Key Vocabulary – Define these terms using your notes page External fertilization6. Genotype 2.Internal fertilization 7. Phenotype 3.Gene 8. Dominant 4.Allele 9. Recessive 5.Trait

So what is a gene? Key Point #1 A gene is one section of a Chromosome that contatins specific genetic information.

this is a chromosome this is a ____Gene______ gene

So what do genes do? Key Point# 2: Genes give us a specific trait. A trait is a characteristic or property of an organism.

These are all examples of __inherited___ traits. Remember, the word “inherit” comes from the word _____Heredity______, which means “information is passed down from parent to offspring.” What can we say about the relationship between genes and inherited traits? Genes DETERMINE our traits!

An example of an inherited trait is the ability to roll your tongue. Can you roll your tongue?

What would happen if… Your mom can roll her tongue, and she passed that gene to you. Your dad can not roll his tongue, and he passed that gene to you. Will you be able to or not? You have two different forms of the same gene.

KP #3 A gene can have many different alleles. When these different forms match up on a pair of chromosomes, they interact and code for a trait.

Gene that controls hair Widow’s peak (triangle- shaped hair line) No widow’s peak (straight hair line) Same _________(hairline) Different ______ (widow’s peak or no widow’s peak)

Gene that controls: texture of Hair Form: A Form: a Different forms of the same ___________

KP #4 When genes pairs match up on homologous chromosomes, they code for a trait.