1. Mendelian Genetics Part 2

2. Learning Objectives
Describe the results of Mendel’s crosses on pea plants.

3. Mendel’s 7 Traits
Mendel studied seven different pea plant traits, each with two contrasting characteristics.
He crossed plants with contrasting traits and studied their offspring.

4. What are Gametes?
Gametes - reproductive cells (sperm & egg) that unite at fertilization to form a new organism.

5. Mating Vocabulary Parental (P) - original pair of purebred plants
First Filial (F1) - first generation offspring
Second Filial (F2) - second generation offspring

6. Cross of Parental Tall and Short Pea PlantsX
Homozygous
Alleles
Each parental (P) plant produces 1 type of gamete

7. Parental Cross PhenotypeF1 X
Mendel crossed the parental tall with the parental short pea plant producing the F1 generation.
All F1 plants were tall.

8. Mendel’s Law of Segregation Parental Cross Genotype
Allele Pairs:
T = tall t = short X P
Cross parental plants.
Allele pairs separate.
Gametes carry a single copy of a gene
3. All F1 offspring carry the dominant allele.
Gametes T T t t F1 Tt Tt Tt Tt

9. The Results of Mendel’s Parental Crosses on Pea Plants
100% of the F1 offspring showed the dominant phenotype.

10. Segregation of Chromosomes
YouTube Video
Segregation of Chromosomes