GENETICS
Genetics- __________________________________.
Heredity- the passing down of traits/_________________ from one generations to the
_________.
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_______________ ____ ___L
The father of Genetics.
______________________.
Worked with _______________.
Not fully appreciated until _____________________.
Born _______________________.
1st Scientist to put ________and _________ together.
Why Pea Plants?
Short Life Cycle…____________.
No ________________ traits.
They could ______________or be ___________________ by hand.
o
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Gametes____________. Like an egg or sperm
Haploid Cell is a cell that only contains __________________________________…like
gametes!!
o _______________- has a full number of chromosomes. Like every cell in your body
EXCEPT your gametes.
Pea Plants
A Pea plant has both the _________and _________ gametes enclosed within the
flower.
________ grains are the _______ haploid cells.
________ are the female haploid cells.
o
The __________ can fuse together to make a viable offspring called a
____________ in a process called ______________________.
o Or the gametes can be bred by hand….called __________________________.
EXPERIMENTS
 Mendel began his experiment by allowing a given variety to self-fertilize for
several generations. This assured what he called a purebreed.
 He crossed a :
tall X tall = all tall
 Then he would take and cross
 Tall X Short (also a purebreed) = All Talls in the F1 generation.
 Through this he discovered what are called _________________…which is the
trait observed in a ________.
 ____________________-a trait that is _____ observed in hybrid.
MENDEL’S PEA PLANTS
 After many experimental crosses Mendel determined that many traits of the pea plants were
________/_______________.
 He established a _______ that is stilled ___________ used today.
 Copy the chart in its entirety.
Dominant Traits will be represented by ____________ Letters.
Recessive Traits will be represented with ___________ ___________ letters.
TRAITS
o
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You determine which letter to use by taking the ____________ of the _____________trait
REMEMBER- ___________________represents _____ trait (Height is one trait so it includes
tall and short…still one letter)
If you _______ letters than you change __________.
CONCLUSION
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During Mendel’s work he concluded that each trait was controlled by something he called a
__________…we know today he was talking about _________.
He then continued by saying that each trait is really controlled by ______ “factors”,alleles, or
genes…________________________________.
o Therefor the gametes of an individual contain ______ factor for a _______.
REMEMBER:
names.
________,_________, and “factors” are all the same thing…just different.
GENOTYPE
GENOTYPE- the _____________________________ of an organism.
PHENOTYPE
PHENOTYPE- the form of the trait that is ________________________.
TT
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tt
HOMOZYGOUS
An organism where the _______ _________ for a trait are the same.
Can be ____________ or recessive.
Tt
Also called Pure Breed
HETEROZYGOUS
o An organism where the two alleles for a trait are ______________.
___________.
Also called a
Mendel’s Law
The chromosomes of homologous pair are made of __________ sequences called
________…therefor they have _______copies of a gene for any given trait.
 The Law of Segregation-That each pair of alleles separates during Meiosis
o The Law of Dominance-When two alleles for a given trait are different (hybrid) one allele
will be dominant over the other.
o Law of Independent Assortment - The alleles/gene pairs separate into gametes
randomly and independently of each other. (Those alleles located on different
chromosomes).
Randomly- You have no control.
Independently- One trait has no control on another.
PROBABILITY
PUNNETT SQUARE
A ______for _____________ genetic information.
RULES FOR THE PUNNETT SQUARE
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Determine the __________of the __________.
Put one parent on _____ one parent far left. Do not _______ Parents
Combine __________ inside the grid.
Determine ____________ and ______________ Ratios
PRACTICE TIME
DO THE FOLLOWING CROSS
Cross a heterozygous tall pea plant with a short pea plant.
Tt X tt
RATIO
Phenotypic Ratio: 2:2 (reduce down)
Tall:short
Genotypic Ratio: Tt:tt
2:2 (reduce down)
PUNNETT SQUARE
o
MONOHYBRID CROSS- Cross that involves only __ trait. Simple Punnett square.
o
DIHYBRID CROSS- Cross that involves __ traits. A Punnett square that has 16 squares.