Download presentation
Presentation is loading. Please wait.
1
Genetics and Heredity Our Hero Gregor Mendel
2
Mendle’s Pea Experiment Height-Tall vs Short Seed Shape-Round vs Wrinkled Seed Color-Yellow vs green Flower Color- Purple vs White Flower Position- Axial vs Terminal Pod shape- Inflated vs Constricted Pod Color- Green vs yellow
3
Anatomy of a Flower
5
Making A Punnett Square
6
Gametes TT X tt Male Female
7
Completed Square TT Male X tt Female T T t t
8
Terminology Homozygous-two of the same alleles for a given trait Dominant Recessive Heterozygous-each cell of an organism contains two different alleles for a given trait Example:
9
Tt X Tt
10
More Terminology Genotypic Ratio- the combination of alleles for a given trait (gene combination) Phenotypic Ratio- a ratio of what the offspring look like
11
Test of Segregation Test cross Rr X rr RR X rr
12
Mendle’s Conclusions Principle of Dominance- one form of a hereditary trait (dominant), dominates or prevents the expression of the recessive trait. Principle of Segregation- during gamete formation the pair of genes responsible for each trait separates so that each gamete receives only one gene for each trait.
13
IncompleteIncomplete Dominance
14
DihybridDihybrid Cross
15
THE PRINCIPLE OF INDEPENDENT ASSORTMENT GENES FOR DIFFERENT TRAITS SEGREGATE INDEPENDENTLY DURING GAMETE FORMATION
16
Multiple Alleles-Codominance Blood type A Blood type B Blood type AB Blood type O IAIAIAIA I A i O IBIBIBIB IBiOIBiO IAIBIAIB iOiOiOiO G e n o t y p e s
17
Mendel’s Work Revisited In the early 1900’s Walter Sutton observed meiosis in grasshoppers. He concluded that chromosomes do indeed behave like Mendel had thought. It also started the idea that genes are on the chromosomes.
18
Thomas Hunt Morgan His work was on fruit flies Experimented with the sex chromosomes X and Y chromosomes differ between the sexes so they are called sex chromosomes The other chromosomes are called autosomes
19
Sex Determination MaleFemale
20
Sex-Linked Inheritance XRXRXRXR XrYXrY Red Eyed FemaleWhite Eyed Male
21
Can We Get A White Eyed Female? XRXrXRXr XrYXrY Red Eyed FemaleWhite Eyed Male
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.