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M E N D E L I A N G E N E T I C S. Mr. Carpenter’s Science Emporium . INTERACTIVE POWERPOINT. Bell-work QUESTIONS. Type in your own focus question here Type in your own focus question here Type in your own focus question here Type in your own focus question here
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MENDELIAN GENETICS Mr. Carpenter’s Science Emporium INTERACTIVE POWERPOINT
Bell-work QUESTIONS • Type in your own focus question here • Type in your own focus question here • Type in your own focus question here • Type in your own focus question here • Type in your own focus question here Page 1 of 20 Mr. Taylor’s Science Emporium of Knowledge, 2013 Revision No.1
GREGORMENDEL 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. fruit flowers trees Monastery gregor priest Variation in plants Traits are passed from parents to offspring tested 28,000 Page 1 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
GREGORMENDEL • 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? Page 2 of 20 Mr. Carpenter’s Science Emporium of Knowledge , 2013 Revision No.1
GREGORMENDEL • 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 ____________________________. female male Fertilize the eggs On the same plant Page 3 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
GREGORMENDEL 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 Page 4 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
GREGORMENDEL • 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 Page 5 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
Plant COLOR Plant SHAPE Plant HEIGHT GREGORMENDEL Mendel’s plant characteristics that he studied: Result = or Result = or Result = or TALL SHORT ROUND WRINKLED PURPLE WHITE The two forms for each characteristic above are called __________. TRAITS Page 6 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
GREGORMENDEL 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 ______________________________. traits True breeding Self-pollinating: plant will always produce offspring with the same trait the parent plant has tall crossed mated Cross-pollination Page 7 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
GREGORMENDEL • 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. Page 8 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
GREGORMENDEL 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 Page 9 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
GREGORMENDEL 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? Page 10 of 20 Mr. Taylor’s Science Emporium of Knowledge, 2013 Revision No.1
GREGORMENDEL 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. Page 11 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
GREGORMENDEL 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 Page 12 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
GREGORMENDEL • 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 Page 13 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
PUNNETTSQUARES 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 Page 14 of 20 Mr. Carpenter’s Science Emporium of Knowledge , 2013 Revision No.1
PUNNETTSQUARES 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 Page 15 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
PUNNETTSQUARES • 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 Any other color If an individual has the genotype of bb, they will have what color eyes? different heterozygous hybrid Page 16 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
PUNNETTSQUARES 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... [_____________] PRACTICEFor 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 He ANSWERS LIE BEHIND THIS BOX NO PEEKING He Ho Ho He He Ho Ho Bb, Tt, Ss, Rr, and Ss SS, BB, and TT Page 17 of 20 Mr. Taylor’s Science Emporium of Knowledge, 2013 Revision No.1
PUNNETTSQUARES 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 Page 18 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1
PUNNETTSQUARES 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 Page 19 of 20 Revision No.1
PUNNETTSQUARES b b b B b b b B 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 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)? Page 20 of 20 Mr. Carpenter’s Science Emporium of Knowledge, 2013 Revision No.1