Mendel And His Peas Flashcards
Physical characteristic
A physical feature that helps to distinguish an organism or thing
Example: hair color
Heredity
The passing of traits from parents to offspring
Trait
The different forms of a specific physical characteristics
Example: brown hair, blonde hair, etc.
Gregor Mendel
He discovered the principles of heredity through his study of pea plants.
Because of his discoveries, he is known as “the father of genetics.”
Genetics
The scientific study of heredity
Why were pea plants a good choice
Each characteristic only has two possible traits.
Produce a large number of offspring.
-Easy to collect large amounts of data to study.
Grew quickly.
-The study can be completed faster.
Self pollinating plants
Plants fertilize themselves because they contain both male and female reproductive structures.
Both the male and female part has the exact same DNA.
They will be the exact copies of their parents.
Cross pollinating
One plant can fertilize a different plant.
Cross-pollination occurs when wind or animals carry pollen from one plant to another.
Offspring will not be the exact copies because DNA from the two plants is different.
How did Mendel cross pollinate his plants
He did this by removing the female reproductive parts of one plant and the male reproductive part of the other plant and pollinating the plants by himself
Mendel’s first experiment
Mendel cross- pollinated a purebred plant displaying one trait (tall) with a purebred plant displaying the other trait (short)
Dominant trait
The trait that showed up in the F generation
Recessive trait
The trait that disappeared in the F generation
Mendel’s second experiment
Mendel allowed the F1 generation to self pollinate
The offspring were a mixture of tall plants (dominant trait) and short plants (recessive trait) even though both parents(F1 generation) were tall
What is The F2 generation
The offspring of the F1 generation
What is the F1 generation
The offspring of the parent generation
Mendel’s second experiment results
Mendel got the same results in the F2 generation for each of the seven characteristics: a mixture of the dominant and recessive trait
Ratios and Mendel’s experiment
Mendel counted the numbers of plants showing the dominant trait or the recessive traits in the F2 generation
Every time the recessive trait showed up less often
For every three plants showing the dominant trait only one plant showed the recessive trait (3:1 ratio)
Gregor Mendel- gone but not forgotten
Mendel realized that his results could only be explained if each plant had two sets of instructions (alleles) for each characteristic
Each parent has two sets of instructions(alleles), but only one of those alleles can be passed on to their offspring
Alleles
Pieces of DNA that contain instructions for different characteristics and their traits
What is each characteristic represented by?
Two alleles, one from each parent
The difference between allele and a trait
An allele is the actual DNA instructions, the trait is what the organism looks like because of the instuction
Dominant and recessive alleles
The dominant allele masks or hides the recessive alleles
The dominant allele is what makes the trait dominant, so the dominant allele is the same as the dominant trait
