Genotype, Phenotype, Purebred Breeding, and Crossbreeding

1. Genotype, Phenotype, Purebred Breeding, and Crossbreeding

2. Objectives • Define genotype and phenotype and know the differences with 100% accuracy. • Define purebred breeding and crossbreeding and know the differences with 100% accuracy. • Identify examples of genotype and phenotype in animals with 80% accuracy. • Identify purebred and crossbred animals with 80% accuracy.

3. Key Terms • Genotype: Genetic makeup of an animal. • Phenotype: The outward expression of a gene. • Purebred Breeding: The breeding of animals within the same breed. • Crossbreeding: The breeding of two different pure breeds. • Codominance: a cross between organisms with two different phenotypes produces offspring with a third phenotype in which both of the parental traits appear together.  • Incomplete dominance: a cross between organisms with two different phenotypes produces offspring with a third phenotype that is a blending of the parental traits. 

4. Why? • Why should we know the difference between genotype and phenotype? • Why should we know the difference between purebred and crossbred animals? • Why should we know how to identify animals that are purebred or crossbred?

5. What? • What is the difference between genotype and phenotype? • What is the difference between purebred and crossbred? • What are examples of animals that are purebred and crossbred?

6. What is the difference between genotype and phenotype? • Genotype: Genetic makeup of an animal. • Genotype is in the gene. It is something that we cannot directly see. • Phenotype: The outward expression of a gene. • Phenotype is the characteristic of the animal that we can see. Ex, Holsteins are black and white.

7. What is the difference between purebred and crossbred? • Purebred Breeding: The breeding of animals within the same breed. • Ex, Angus breeds with Angus not with Red Angus • Crossbreeding: The breeding of two different pure breeds. • Ex, Angus can breed with Red Angus

8. What are examples of animals that are purebred and crossbred? • What are examples of animals that are purebred and crossbred? • Animals are considered pure bred when they meet all the characteristics of the breed. • Owners of the animal will be able to track the lineage of the animal to ensure heritage. • Many ranches will have a purebred stud. • This can bring in a lot of money due to other owners wanting their females to breed with a purebred.

9. Codominance A cross between organisms with two different phenotypes produces offspring with a third phenotype in which both of the parental traits appear together.  redxwhite--->RED & WHITE SPOTTED R = allele for red flowers W = allele for white flowers red x white ---> red & white spotted RR x WW ---> 100% RW

10. Incomplete dominance A cross between organisms with two different phenotypes produces offspring with a third phenotype that is a blending of the parental traits.  RED Flower x WHITE Flower ---> PINKFlower R = allele for red flowers W = allele for white flowers red x white ---> pink RR x WW ---> 100% RW

11. Project • Create a new breed of animal. • Crossbreed two breeds of animals to get desired traits. • Needs to show multiple characteristics and have a punnett square for each one. • EX). Body type, hair/fur color, body size, ect. • Must use at least one codominant or incomplete dominant trait. • Draw an example of your creation. • Name your creation. • Present to the class what you made and how.

12. Review • What is the difference between genotype and phenotype? • What is the difference between purebred and crossbred? • What are examples of animals that are purebred and crossbred?