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Period:
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Mendelian Genetics Review Sheet
Part I: Experimental Genetics Began In an Abby Garden
Gregor Mendel was an (1)
monk who lived in the (2)
hundreds.
He was trained in mathematics and science but spent most of his life tending the (3)
at
his monastery. During this time he performed experiments on ordinary garden (4)
.
Part II: Mendel’s First Set of Experiments Led To The Development Of Four Hypothesis
In Mendel’s first experiments he forced the garden peas to mate with themselves in a process called
(1)
- fertilization. These plants were (2)
-breeding, because, in effect, when they self-
fertilized they created offspring identical to themselves. This is also called true bred. Once Mendel had
established two pure lines, for example pure purple and pure white flowers, he (3)
-fertilized
these two different pure plants. In this experiment the true-breeding parents were the (4)
generation while the hybrid offspring where the (5)
generation. Then, Mendel self-
(6)
the F1 generation resulting in 929 F2 offspring. 705 of the offspring were
purple while (7)
were white. Mendel continued to experiment with a total of (8)
traits.
Each one produced the same overall results. This led him to create the following hypotheses:
1. There are alternative forms of genes called (9)
.
alleles – one from each parent.
2. For each characteristic (trait) an organism has (10)
3. When two alleles are different, the one that is expressed is (11)
hidden is(12)
, while the one that is
.
4. The sperm and egg are able to carry only one allele for each gene because the alleles (13)
during gamete production. This is called the Law of (14)
Practice Punnett Square:
Heterozygous Purple x Heterozygous Purple
.
An example of Mendel’s First Set of Experiments:
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Part III: Mendel’s Second Set of Experiments Led To His Second Law
In Mendel’s second set of experiments he looked at (1)
again started with true-(2)
traits at one time instead of only one. He
parents, for example a pure round and yellow seeded pea with a
pure wrinkled and green seeded pea. When he completed this cross he noticed that all of the offspring were
(3/4)
(5)
the (6)
round,(8)
&
. These offspring, the F1 generation were all
, or heterozygous. Then Mendel mated the F1 generation with themselves producing
generation. Here he saw a distinct ratio. Out of 16 offspring, (7)
were yellow and wrinkled,(9)
were yellow and
were green and round, and 1 was green
and wrinkled. This finding led him to his second law, the law of (10)
. This law states that alleles for different (11)
segregate
independently.
An example of Mendel’s Second Set of Experiments:
Practice Punnett Square:
Heterozygous Round & Yellow x Wrinkled & Green
Part IV: Mendel’s Laws Were Founded On Probability And Have Been Confirmed By Science
It turns out that Mendel’s actual results were very similar to the predicted results created from a tool called
the (1)
Square. It makes sense that they would not be identical because these squares are
based on (2)
not reality. According to probability two different true-breeding
parents (HH x hh) should create (3)
a dominant(4)
with (5)
offspring (Hh). These offspring would all show
. Then, when the offspring mate (Hh x Hh) they should produce plants
/4 dominant and (6)
/4 recessive phenotypes.