I. 9-1 Mendel’s Legacy A. Gregor Mendel

1. Mendel observed ___________________ characteristics of pea

plants that occurred in two contrasting ____________________

2. Examples: ___________________________________________ pod

appearance, seed texture, seed color, and flower color

3. He carefully collected seeds and noted the characteristics of the plant

from which they came.

4. The following year he planted the seeds. Seeds that came from

plants with purple flowers would bloom with _________________,

but he also noted some ______________________ in the mix. He

also noted that short plants grew from the seeds collected from tall

plants.

B. Mendel’s Methods

1. Mendel wanted to document the traits of __________________ of

pea plants

2. He did this by controlling the _____________________ of the plants

Removed the ____________ (male part containing pollen)

from one plant and transferred to the ____________ (female

part of plant) of another plant

C. Mendel’s Experiments

1. Started with plants that were _____________ for each trait

2. Meaning that it will always produce offspring with that same trait

3. ____________ – pure for a specific trait, 14 total with the pea plants

4. Strain of pure wrinkled seeds, strain of pure smooth seeds

5. _______________________ – the parental generation of each strain

6. To start his experiments, he ___________________________

opposing traits with one another (yellow pods with green pods)

7. First filial generation, _______________________ the offspring

with this cross

8. Next he allowed the offspring (F1 generation) to self-pollinate,

getting the second filial generation, the _______________________

D. Mendel’s Results and Conclusions

1. In the P1 generation, Mendel crossed a pure green pod plant with a

pure yellow pod plant, but in the F1 generation he only got

____________________________

2. In the F2 generation, when the plants self-pollinated, he ended up

with _____________ green pods and _______________ yellow pods

3. Because of this, Mendel concluded that there must be a pair of

“_________________” controlling each trait

4. The trait that appeared in the F1 generation that masked or

“dominated” the other factor is called a

________________________

5. The trait that shows up in ¼ of plants in the F2 generation and is

masked by the other factor is called the

________________________

6. In our example, the green pea pods are ________________ to the

yellow pea pods

E. Remember from Chapter 8…

1. Chromosomes are made up of ____________, and DNA makes up

our _________________, or the traits that we carry

2. Chromosomes occur in _____________, so genes also occur in pairs

F. Two Laws of Heredity

1. Law of Segregation

A pair of factors is ____________________________, or

separated, during the formation of gametes

Each gamete has one half of a homologous pair of

chromosomes, and the genes are located on the chromosomes,

which means each gamete only contains

____________________

When gametes combine, the zygote will contain

_____________________ to control a specific trait

2. Law of Independent Assortment

Factors for different characteristics are distributed for gametes

__________________________

This means that alleles for different characteristics are

_______________________ (appear on different chromosomes)

Example: A green pea pod produced by a dominant allele could

appear in a white-flowering plant, which is produced by a

recessive allele