1. INTERACTIVE POWERPOINT
MENDELIAN GENETICS
Mr. Carpenter’s Science Emporium
INTERACTIVE POWERPOINT

2. Bell-work QUESTIONS Type in your own focus question here
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3. Traits are passed from parents to offspring
GREGOR MENDEL
A. Gregor Mendel was born in 1822 in Austria. Growing up on his family’s farm he had a lot of practice cultivating ____________ and _________
__________. As a young man he attended the Institute in Olomouc. After completing his studies he began work in a __________________. There he changed his name from Johann to _____________. In 1847, he was ordained as a ___________. Mendel was inspired by both his professors and his colleagues at the monastery that he started his own work. He tried to unravel the mystery of ____________________________. He also studied the ways __________________________________
_________________________________________. Between 1856 and 1863 Mendel cultivated and __________ some _____________ pea plants.
flowers
fruit
trees
Monastery
gregor
priest
Variation in plants
Traits are passed from parents to offspring
tested
28,000
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4. GREGOR MENDEL
B. Mendel’s Research – Unraveling the Mystery
Mendel’s attraction to research was based on his love of nature. He was not only interested in plants, but also in ____________________ and the theory of _______________.
Mendel always wanted to find out how plants obtained _______________ characteristics. Mendel knew that sometimes the _______________________________ seemed simple and sometimes they did not.
meteorology
trees
evolution
atypical
Pattern of inheritance
For example, sometimes a trait that appeared in first generation did not show up in any of the offspring in the second generation. Interestingly, in the third generation, the trait showed up again. Mendel also noticed similar patterns in people and many other living things. How can this be?
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5. GREGOR MENDEL C. Mendel’s Pea Plants
To simplify his investigation, Mendel decided to study only one kind of organism. He had already done studies using the _______________________, so he chose this as his subject.
Why did Gregor Mendel use pea plants? Garden peas were a good choice for several reasons:
___________________________________
Garden pea plant
Grow quickly
Usually self-pollinating
Many variations
Self-pollinating plant:
Self-pollinating plants contains both _________ and ____________ reproductive structures.
Pollen from one flower or plant can ________________________ of the same flower or eggs of another flower ____________________________.
male
female
Fertilize the eggs
On the same plant
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6. GREGOR MENDEL Pollination:
______________________________________________________________________________________________________
Fertilization:
________________________________________________________________________________________________________________________________________
Pollen from the anthers (male) is transferred to the stigma (female)
A sperm from the pollen travels through the stigma and enters the egg in an ovule
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7. GREGOR MENDEL D. MENDEL’S GAMEPLAN
After deciding to use pea plants as his subject, he chose to study only __________________________ at a time.
That way, it is easier to identify which _____________ should be included or eliminated.
These characteristics included:
__________
Mendel chose plants that had ____ forms for each of the characteristics he studied.
One characteristic
variable
height
shape
color 2
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8. GREGOR MENDEL Plant SHAPE Plant COLOR
Mendel’s plant characteristics that he studied:
Result = or
Plant HEIGHT
TALL
SHORT
Plant SHAPE
ROUND
WRINKLED
Plant COLOR
PURPLE
WHITE
The two forms for each characteristic above are called __________.
TRAITS
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9. GREGOR MENDEL True breeding (pure-bred) in plants:
E. True-Breeding Plants & Cross-pollination
Mendel was very careful to use plants that were _______________________ for each of the _________ he was studying.
True breeding (pure-bred) in plants:
____________________________________________________
Example: A tall true-breeding or pure-bred plant will always produce offspring that are _________.
Mendel decided to find out what would happen if he ___________ or __________ two plants that had different forms of a single trait. To do this, he used a method known as ______________________________.
True breeding
traits
Self-pollinating: plant will always produce offspring with the same trait the parent plant has
tall
crossed
mated
Cross-pollination
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10. GREGOR MENDEL Cross-pollination in plants:
____________________________________________
The anthers of one plant are removed so that the plant cannot self-pollinate. Pollen from another plant is used to fertilize the plant without anthers
This way, Mendel could have control of his experiments by selecting which pollen would fertilize which plant.
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11. *** PARENT GENERATION ***
GREGOR MENDEL
F. MENDEL’s FIRST EXPERIMENT
In Mendel’s first experiment, he performed crosses to study seven different characteristics. Each of the crosses was between the two traits of each characteristic.
To study these different characteristics, he performed a __________ (fertilization) between plants that produce ______________ seeds and plants that produce __________ seeds.
The offspring from this cross are known as the _____________________. See figure to the left.
*** PARENT GENERATION ***
WRINKLED SEEDS
ROUND SEEDS X
*** F1 GENERATION ***
cross
wrinkled
round
All round seeds
First (f1) generation
Write the result of the F1 generation to the left 
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12. “So, what happened to the wrinkled peas? What should I do next?”
GREGOR MENDEL
In each of his crosses, Mendel observed similar results. One trait always appeared, and the other traits seemed to disappear.
To organize his observations he labeled the trait that appeared as the ______________ traits. Based on the F1 generation, which of the following two traits are dominant? ____________
The trait that seemed to disappear he called the _______________ traits. Which of the following two traits are recessive? _______________
“So, what happened to the wrinkled peas? What should I do next?”
dominant
round
recessive
wrinkled
What happened to the recessive trait?
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13. GREGOR MENDEL G. MENDEL’S SECOND EXPERIMENT
Mendel allowed the F1 or first generation from each of the seven crosses to self-pollinate.
Mendel allowed the F1 or _______________________ offspring of the dominant trait for seed shape (which is round) to self-pollinate.
The offspring from this self-pollinating cross is called the _________________________________. In this generation the trait for _______________________ showed up again. See figure on the right!
FIRSt generation
F2 or Second generation
Wrinkled shape
No matter which characteristic Mendel investigated, when the F1 generation was allowed to self-pollinate, the recessive trait reappeared.
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14. __________ : __________
GREGOR MENDEL
H. A FIRST TIME FOR EVERYTHING
For the first time recorded, Mendel did something that no one else had done before:
He decided to
________________________________ with
each trait that turned up in the __________________________. He hoped that this might help him explain his result. The results can be seen to the right?
Mendel decided to calculate the _______ of ________________ traits to _____________ traits for each characteristic.
In the space to the right write the ratio for each characteristic in the F2 generation?
Count the # of plants
Second generation
ratio
dominant
recessive
__________ : __________ 3 1
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15. These sets of instructions are called genes.
GREGOR MENDEL
I. PUTTING IT ALL TOGETHER
Mendel realized that his results could be explained only if each plant had _______ sets of instructions for each characteristic. Even though, at the time, Mendel did not know about DNA, he realized that a set of instructions are passed down from the parents to the offspring. In fact, each parent donates a _____________________________ to the offspring. 2
Set of instructions
These sets of instructions are called genes.
Genes:
Alleles:
a segment of dna that has a set of instructions for a particular trait
An alternate or different form of a gene
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16. PUNNETT SQUARES
To mathematically understand Mendel’s conclusions it is important to use a tool called a ______________________.
PUNNETT SQUARE
Punnett Square:
__________________________________________________________________________________________________________________________________________
Punnett Squares use two different types of alleles. One set comes from each parent’s ______ cells. The father contributes ________ while the mother contributes an ______. To represent the allele from each parent, ___________ are assigned.
These letters represent the genotype of which ____________ you are looking for as a result of the Punnett square.
A TOOL USED TO VISUALIZE ALL POSSIBLE COMBINATIONS OF THE ALLELES FROM THE PARENTS
SEX
SPERM
EGG
ALLELES
ALLELES
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17. PUNNETT SQUARES Genotype: J. How to write a Genotype:
J. How to write a Genotype:
All traits are shown with _____ letters. One set from each parent’s sex cells _________ or ______. Letters are used to represent different forms of genes called ___________.
Example of alleles
Some alleles are ________________ and are shown with _______________________ [BB or B].
Some alleles are _______________ and are shown with __________________________ [bb or b].
When writing a genotype always put the _______________________ or capital letter first.
THE GENETIC COMPONENT OF THE TRAIT OR THE INHERITED COMBINATION OF GENES 2
SPERM
EGG
ALLELES
DOMINANT
CAPTIAL LETTERS
RECESSIVE
LOWERCASE LETTERS
DOMINANT ALLELE
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18. PUNNETT SQUARES Example:
B = is a ______________ allele (form of gene) for brown eyes
b = is any other eye color which is a ______________ allele (form of gene)
Answer the following questions:
The prefix hetero means ______________. Therefore, alleles written by [1] capital letter and [1] lower case letter is called ____________________.
Example: Bb, Aa, Ss, Tt, etc… [ __________ ]
DOMINANT
RECESSIVE
If an individual has the genotype of BB or Bb they will have what color eyes? 
BROWN
If an individual has the genotype of bb, they will have what color eyes? 
Any other color
different
heterozygous
hybrid
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19. ANSWERS LIE BEHIND THIS BOX
PUNNETT SQUARES
The prefix homo means ____________. Alleles represented by [2] capital letters or [2] lower case letters are called __________________.
Example: BB, bb, AA, aa, SS, ss, etc... [_____________]
PRACTICE For each GENOTYPE below, indicate whether the following alleles are heterozygous (He) or Homozygous (Ho).
Using the chart above write which of the following are hybrids? ______________________________
Using the chart above write which of the following are purebreds? ___________________________
The same
homozygous
purebred
“GOOD JOB!” He Ho Ho Ho
ANSWERS LIE BEHIND THIS BOX He
NO PEEKING He Ho He Ho He Ho Ho
Bb, Tt, Ss, Rr, and Ss
SS, BB, and TT
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20. PUNNETT SQUARES K. PHENOTYPES
A phenotype is ____________________________
_________________________________________
An organism’s phenotype is all of its observable characteristics—which are influenced both by its _______________ and by the ________________.
Remember: A change in the environment can change an organism’s phenotype but not the genotype. Flamingos turn pink because of the food they eat and not by their genotype.
Genotypes (e.g. BB, Bb, bb) determine the visible trait or phenotype (e.g. Brown, Brown, blue)
An observable trait of anything living
genotype
environment
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21. PUNNETT SQUARES L. PUNNETT SQUARES
One way to visualize how genes combine is through the use of _______________________. By using Punnett squares you can work out the ___________________ that children of the parents will have specific phenotypes and genotypes.
Remember that ______________ alleles are symbolized with capital letters, and ______________ alleles are symbolized with lowercase letters.
Monohybrid cross:
_______________________________________
______________________________________________________________________________
Punnett squares
probabilities
dominant
recessive
A cross between two different alleles for a single trait
Mr. Carpenter’s Science Emporium of Knowledge
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22. What % of the parent’s offspring will have blue eyes (bb)?
PUNNETT SQUARES
EXAMPLE:
Let’s say we cross a mother with a phenotype of blue eyes (genotype bb) with a father who has the phenotype brown eyes (Bb). Brown eyes are Dominant to blue eyes. What is the chance that any of the offspring will have blue eyes?
Step #2: _______________________________
_______________________________
Step #3: _______________________________
Step #4: _______________________________
Step #1: Draw a 4x4 box to setup your monohybrid cross. B b
Write the genes of the father across the top b B b b
Write the genes of the mother down the side b
Fill in box with the appropriate alleles 50 %
What % of the parent’s offspring will have blue eyes (bb)?
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