In humans each gene has two alleles . Each parent contributes one allele for a trait.

1. Organisms have thousands of genes, organized into chromosomes, which determine what the animal looks like and what it can do.

2. In RoboRiot each robot has one gene with two “alleles”. Each robot contributes one “allele” to the recycler.

3. In humans each gene has two alleles. Each parent contributes one allele for a trait.

4. Heredity:An offspring gets one allele related to a traitfrom each of its parents. The two alleles are responsible for that trait in the offspring. Alleles determine trait

5. When the two alleles in a gene are the same for a trait, the gene is homozygous. When the two alleles in a gene are different for a trait, the gene isheterozygous.

6. When an organism has two alleles that are the same for a trait, both determine the trait. When an organism has two different alleles for a trait, only one trait is expressed.

7. The allele that determines the trait is called dominant. dominant Trait: brown eyes The allele that is not expressed as a trait is called recessive. recessive

8. All the information in the genes, both dominant and recessive, defines an organism’s genotype. The appearance of an organism is called its phenotype.

9. browneyes For the trait of brown or blue eye-color in humans, there are three possibilities: blueeyes browneyes Because brownis dominant and blueis recessive.

10. Eye-color Genotype Possibilities homozygous brown homozygous brown homozygous brown homozygous brown homozygous brown homozygous blue homozygous blue homozygous blue homozygous blue heterozygous brown heterozygous brown homozygous brown heterozygous brown heterozygous brown homozygous blue heterozygous brown heterozygous brown homozygous blue heterozygous brown

11. The alleles in some genes are neither dominant nor recessive. Both alleles are expressed when the genotype is heterozygous. This is called co-dominance. Blood Type Blood Type Blood Type B B B A A A A B

12. The phenotype is the result of both alleles The genotype is always heterozygous When alleles are co-dominant: AA BB BB AA AB

13. A species is defined as organisms that resemble one another, can mate, and produce offspring that can reproduce. etc…