# PRE UNIT STATEMENTS POST 1 Offspring inherit 4 sets of instructions for each characteristic. 2 Different versions of the same gene are known as genes. If both the dominant allele and the recessive allele are inherited for a 3 characteristic, only the dominant allele is expressed. 4 A genotype is the physical expression of the phenotype. Probability is the mathematical chance that an event will occur. It is usually 5 expressed as a fraction or as a percentage. Dominant traits are apparent only when two recessive alleles for the 6 characteristic are inherited. 7 A genotype is the combination of alleles for a particular trait 8 The set of instructions transmitted to parent to offspring are called genes. 9 Gregor Mendel used dandelions to study heredity. 10 Heredity is the passing of traits from parents to offspring. 11 A fertilized egg has two forms of the same gene for each trait. When a true-breeding plant self-pollinates, it will always produce offspring 12 with the same trait the parent plant has. 13 The offspring resulting from the parental cross is called the F2 generation. 14 *** MENDELIAN GENETICS *** Instructions: After reading the statements below, choose either A for agree or D for disagree. Cross pollination is when the anthers of a plant are removed so that the plant cannot self-pollinate. CLASS PERCENTAGE OF PREASSESSMENT: AGREE 1 2 3 4 5 6 7 8 9 10 11 12 13 14 CLASS PERCENTAGE OF PREASSESSMENT: DISAGREE 1 2 3 4 5 6 7 8 9 10 11 12 13 14 CLASS PERCENTAGE OF POSTASSESSMENT: AGREE 1 2 3 4 5 6 7 8 9 10 11 12 13 14 CLASS PERCENTAGE OF POSTASSESSMENT: DISAGREE 1 2 3 4 5 6 7 8 9 10 11 12 13 14 This packet belongs to: Grade:
*** UNIT VOCABULARY *** TERM DEFINITION TEST QUESTION DOMINANT TRAIT RECESSIVE TRAIT GENES ALLELES GENOTYPE PHENOTYPE PUNNETT SQUARES HYBRID PUREBRED 9 FACTS ABOUT GREGOR MENDEL 1. 2. 3. 4. 5. 6. 7. 8. 9.
*** SCIENCE NOTE LOG *** DATE: PERSONAL JOURNAL NOTES Information cited from : Holt, Rinehart, & Winston. (2002). Cells, Heredity, and Classification. Austin, Texas: Holt, Rinehart and Winston.
*** MENDELIAN GENETICS *** Growing up on a farm, what did Mendel have a lot of practice cultivating? Review: Define the term inheritance? Gregor Johann Mendel (July 20, 1822- January 6, 1884) was an Austrian monk whose studies of the inheritance of traits in pea plants helped to lay the foundation for the later development of the field of genetics. A. THE FATHER OF MODERN GENETICS 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. 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. 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? Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 1
*** MENDELIAN GENETICS *** 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 Mendel choose to use pea plants for his experiments? Why did Gregor Mendel use pea plants? Garden peas were a good choice for several reasons: 1. 2. 3. 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. Pollination: Fertilization: Why are pea plants a good subject to be tested concerning inheritance? Explain how self-pollinating plants reproduce? What is the difference between pollination and fertilization in plants? Unit: MENDELIAN GENETICS Mr. Taylor, 2013 Revision No.1 2
*** MENDELIAN GENETICS *** 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: 1. 2. 3. Why is it important that Gregor Mendel chose only one characteristic at a time when studying pea plants? Mendel chose plants that had forms for each of the characteristics he studied. Mendel s plant characteristics that he studied: Plant HEIGHT Name at least 3 different traits that Gregor Mendel studied in pea plants? Result = or Plant SHAPE Why did Mendel choose two characteristics for each traits? Result = or Plant COLOR Why are pea plants a good specimen to study inheritance? Result = or The two forms for each characteristic above are called. Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 3
*** MENDELIAN GENETICS *** 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. Describe what Mendel meant by crosspollination? Describe what a pure-bred trait is and give one example? 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. Cross-pollination in plants: 1. 2. This way, Mendel could have control of his experiments by selecting which pollen would fertilize which plant. Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 4
*** MENDELIAN GENETICS *** *** PARENT GENERATION *** WRINKLED SEEDS ROUND SEEDS Wrinkled seeds *** F1 GENERATION *** 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. Write the result of the F1 generation to the left What do you think happened to the trait for wrinkled seeds? Why did not appear in the F1 generation? Write your reasoning below: 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? What happened to the recessive trait? Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 5
*** MENDELIAN GENETICS *** 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! No matter which characteristic Mendel investigated, when the F1 generation was allowed to self-pollinate, the recessive trait reappeared. *** PARENT GENERATION *** WRINKLED SEEDS ROUND SEEDS *** F1 GENERATION *** *** F2 GENERATION *** List some traits in your family that have appeared or disappeared from different generations: 1. 2. 3. 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? : Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 6
*** MENDELIAN GENETICS *** 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. These sets of instructions are called genes. Review: Why is it important to mate an individual after the F1 generation? Describe the following terms: Genes - Alleles - Describe the importance of a Punnett Square? Genes: Alleles: To mathematically understand Mendel s conclusions it is important to use a tool called a. Punnett Square: Punnett Squares use two sets of alleles. Where do these sets come from? Why type of cell transmit these allelles? 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. Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 7
*** MENDELIAN GENETICS *** 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]. Some alleles are and are shown with [bb]. When writing a genotype always put the or capital letter first. Example: 1. B = is a allele (form of gene) for brown eyes 2. b = is any other eye color which is a allele (form of gene) Answer the following questions: Put answers here: If an individual has the genotype of BB or Bb they will have what color eyes? If an individual has the genotype of bb, they will have what color eyes? The prefix hetero means. Therefore, alleles written by [1] capital letter and [1] lower case letter is called. Example: Bb, Aa, Ss, Tt, etc [ ] Define the following terms? Genotype: Allele: Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 8
*** MENDELIAN GENETICS *** 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? 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) Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 9
*** 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: 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 #1: Draw a 4x4 box to setup your monohybrid cross. Describe what a Punnett Square is used for? Are recessive alleles assigned lowercased or uppercase letters? Why? Define monohybrid cross? Step #2: Step #3: Step #4: What % of the parent s offspring will have blue eyes (bb)? % Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 10
*** PUNNETT SQUARES *** Interesting fact: Good ideas are often overlooked or misunderstood when they first appear. This was the fate of Gregor Mendel s ideas. In 1865, he published his findings for the scientific community. Unfortunately, his work didn t get much attention. It wasn t until after his death, more than 30 years later, that Mendel finally got the recognition he deserved. Once Mendel s ideas were rediscovered and understood, the door was opened to modern genetics. Practicing and Applying Concepts Predict the offspring from a cross between two hybrid tall pea plants. (T- tall, t-short) 1. What is the genotype for a hybrid tall plant? 2. Use the Punnett Square below to determine the genotypes for the offspring. 3. What is the probability that the plant would be tall? 4. What is the probability that the plant would be short? 5. If you planted 100 seeds from this cross, how many would you expect to be tall? Practicing and Applying Concepts The Punnett square at the left shows the possible combinations of alleles for fur color in rabbits. Black fur, B, is dominant over white fur, b. Given the combinations shown, what are the genotypes of the parents? Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 11
*** PUNNETT SQUARES *** Use the chart above to answer the following questions based on the given genotypes of different alleles. 1. Offspring s alleles: What is the cat s phenotype if the genotype is [HH, Tt, nn]? 2. Write the genotype of a short haired, stripeless cat with no color in its tail? 3. If a heterozygote male cat mated with a homozygote long hair cat, what is the probability that their offspring will be short hair? Use the Punnett square below! 4. Is it possible for an offspring to have long hair if both it s parents had short hair? Explain? Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 12
UNIT NOTE PACKET TEACHER S GUIDE AND
ANSWER KEY
*** MENDELIAN GENETICS *** Name: Mr. Taylor Date: 1/27/2013 UNIT: Genetics LESSON STANDARDS NYS INTERMEDIATE LEVEL SCIENCE 1.2i: The male and female reproductive systems are responsible for producing sex cells necessary for the production of offspring. 2.2a In all organisms, genetic traits are passed on from generation to generation. 2.2b Some genes are dominant and some are recessive. Some traits are inherited by mechanisms other than dominance and recessiveness. 2.2c The probability of traits being expressed can be determined using models of genetic inheritance. Some models of prediction are pedigree charts and Punnett squares. 3.1c Human activities such as selective breeding and advances in genetic engineering may affect the variations of species 4.2a The male sex cell is the sperm. The female sex cell is the egg. The fertilization of an egg by a sperm results in a fertilized egg. NYS HIGH SCHOOL BIOLOGY 2.1a Genes are inherited, but their expression can be modified by interactions with the environment. 2.2a For thousands of years new varieties of cultivated plants and domestic animals have resulted from selective breeding for particular traits. 1.2a Each system is composed of organs and tissue which perform specific functions and interact with each other, e.g. digestion, gas exchange, excretion, circulation, locomotion, control, coordination, reproduction, and protection from disease 1.2b Tissues, organs, and organ systems help to provide all cells with nutrients, oxygen, and waste removal COMMON CORE [6 12] WHST.6-8.8 Gather relevant information from multiple print and digital sources, using search terms effectively; asses the credibility and accuracy of each source; and quote or paraphrase the data and conclusions of others while avoiding plagiarism and following a standard format for citation. BLOOM S TAXONOMY INTEGRATION: [This Lesson is parallel to the following cognition domain] KNOWLEDGE COMPREHENSON ANLAYSIS ASSESSMENT SYNTHESIS EVALUATION Mr. Taylor, 2013 Mendelian Genetics Revision No.1
COMMON CORE STANDARDS WHST.6-8.9 RST.6-8.6 RST.6-8.8 RST.6-8.9 Draw evidence from informational texts to support analysis, reflection, and research Analyze the author s purpose in providing an explanation, describing a procedure, or discussing an experiment in a text Distinguish among facts, reasoned judgment based on research findings, and speculation in a text Compare and contrast the information gained from experiments, simulations, video & multimedia sources with that gained from reading a text on the same text Why is Gregor Mendel is considered the Father of Modern Genetics? Explain how Gregor Mendel unravels the mystery of inheritance? Explain the different types of characteristics in pea plants that Mendel used to study? Describe and discuss Mendel s experiment that lead to the discovery of genetics? Describe how pea plants are good source to test heredity? Explain how pollination leads to fertilization in plants? Define True breeding and self-pollination? Define the term genes and alleles? Describe and use Punnett Squares? Explain how to write a genotype and recognize an organism s phenotype? Understand the different between a dominant and recessive trait? Practice using genotypes to indicate if they are heterozygous or homozygous Describe the difference between hybrids and purebreds? Use a Punnett square to figure out a monohybrid cross? Practice and apply probability concepts of Mendelian genetics through analysis of Punnett squares? Students will be able to. DEEP UNDERSTANDING Discuss why don t all humans look exactly alike? Explain why how Gregor Mendel contributed to the discovery of modern day genetics Compare the differences between self-pollination vs. cross pollination, genotype vs. phenotype, and dominant vs. recessive Describe how to use a Punnett square to figure out the probability of specific traits in the offspring of two parent crosses. Draw a Punnett square and calculate the probability of offspring characteristics Discuss what determines whether a human baby will be a boy or a girl? Explain how genes and alleles are related to genotypes and phenotypes Mr. Taylor, 2013 Mendelian Genetics Revision No.1
MATERIALS Teacher will need: - SMARTboard, SMARTcart, or projector for guided notes, laser clicker - PowerPoint file (Mendelian Genetics PowerPoint if available) - Mendelian Genetics Life Note Packet (1-16) Students will need: - A pen, pencil, guided note packets, science binders, foldables, worksheets WARM-UP EXPLORATORY ACTIVITY ENGAGE, BACKGROUND KNOWLEDGE, BUILD COMMUNITY, ENTICE EFFORT Day 1: Pre-assessment and Note Packet Format Discussion: 1. Handout student note packets. Students will be introduced to a 14 question formative pre-assessment quiz (located on the back of the cover within their note packets) Note: for the pre-assessment, only fill out the top two columns. The last two columns are for the post-assessment which will be given following the completion of this note packet. a. The Class percentage of pre-assessment is designed to access the student s prior background knowledge so that the teacher can get a good idea of how to approach the students within the content of the guided notes. 2. Following the pre-assessment, ask students to raise their hands if they either agreed or disagreed with each question. Put the entire class percentage in the space provided for each questions. It is best to fill out either agree or disagree for time consolidation purposes. After doing so, subtract from the total percentage of the class and fill in the other category. (Example: 1, 2... 1, 90% 2, 70%) Note Packet Initiation 3. After the pre-assessment is complete go over the note packet and explain how each section is designed. On page #2 is the Unit vocabulary sheet. Design any system you want. However, this can be used as homework. As you go over the note packet and they encounter a vocabulary word, have them come back to this page and fill it out. Also, the 9 facts about Gregor Mendel is there for a review assignment. After you have finished teaching about Mendel, have the students come back to this page for a quick 9 fact summary. Make sure you explain to the students that their own facts are to be short and easy for them to remember. 4. Take some time to explain the SCIENCE NOTE LOG section of the note packet. Tell the students that this is their space to take notes, make drawings. They can always come back to this space when they feel that there is extra information that will help them reinforce learned material. I correlate this guided note packet with a PowerPoint. My PowerPoints have movies embedded within them. Every time I play a movie, I ask the students go to their Personal Journal notes and take notes on the movies. Make sure the students write the date when they write their notes. It will help them organize their thoughts. Again, be creative with the use of this page. 5. These notes can be used in many ways. Even though I primarily use them in correlation with an engaging PowerPoint, you can also copy these note as transparencies or hand them out as reading fill-in-the-blank assignments. How to use each page: 1. Each page of the notes is divided into two sections. One section is a note section and the other is a Note Making and Review section. As you go over the notes with your students, stop at the end of each page and have the students work in small collaborative groups to answer the previously learned material. This will act as reinforcement and will help you clear up and misunderstandings. Go over at the end. Mr. Taylor, 2013 Mendelian Genetics Revision No.1
DISCOVERY ACTIVITY GUIDED PRACTICE, APPLICATION, ACTIVE LEARNING, GROUPING, NEGOTIATE MEANING, Note packet Options and Ideas for embedded activities: GRAPHIC ORGANIZER, NOTE MAKING Page #2 1. In the note making section of the notes on page #2, make sure you take some time to demonstrate and review the male and female structures of the a plant before you discuss Pollination and fertilization. Page #4 2. On the bottom of page #4, make sure you extend the lesson by adding a demonstration, or another possible diagram explaining how crosspollination works. Page #5 3. On the top right of page #5, have students write the result of the F1 generation. Go over after with the student and discuss why they chose the answer that they did. Also, have students write down what they think happened to the wrinkled seeds in the space provided. Page #6 4. On the bottom right section of the notes, have students use the chart in the note making section to fill out the ratio of the characteristics. Depending on the level of your students, if you need to, review ratios with your students before you give them this task. Page #8 5. On the bottom of page 8, have the students fill in the two boxes below the picture of the eye. This will introduce them to organizing alleles based on dominance and recessive characteristics. Page #9 6. On the top right of page #9, have students fill in the chart. All they have to do is write He for heterozygous or Ho for homozygous. This section can also be used on a Smart board as well. Page #10 7. On page #11, students will perform two activities. Again, you can use the Smart board for both of them as well. Students will predict the offspring using a Punnett square. Then they will investigate the parents based on the progeny o the lower right side of the notes. This is an introduction model. Page #10 8. On page #12 (last page of notes) have students work on this individually and go over as a class. Once the note packet is complete make sure you include some extra practice with Punnett squares through various mediums. Also, go back and have the students take the embedded post-assessment Mr. Taylor, 2013 Mendelian Genetics Revision No.1
CLOSURE ACTIVITY GUIDED PRACTICE, APPLICATION, ACTIVE LEARNING, GROUPING, NEGOTIATE MEANING, GRAPHIC ORGANIZER, NOTE MAKING 1. Each day, students will end by working on their vocabulary list, studying from the left side of their notes, or working on or finishing any activities that was introduced during the instruction period 2. Extension: Sticky notes on the Whiteboard can be used to summarize what was taught for that day 3. Emphasis on a reflection should be promoted in some way so that not only the students are being assessed, but the teacher as well. LESSON PLAN MODIFICATIONS: Process Product Assessment / Graphic Organizer / Rubric What teacher does: What students do: Reflection on lesson
*** MENDELIAN GENETICS *** Growing up on a farm, what did Mendel have a lot of practice cultivating? Review: Define the term inheritance? Gregor Johann Mendel (July 20, 1822- January 6, 1884) was an Austrian monk whose studies of the inheritance of traits in pea plants helped to lay the foundation for the later development of the field of genetics. A. THE FATHER OF MODERN GENETICS 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 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. 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. 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? Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 1
*** MENDELIAN GENETICS *** 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 Mendel choose to use pea plants for his experiments? Why did Gregor Mendel use pea plants? Garden peas were a good choice for several reasons: 1. 2. 3. 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. Pollination: Fertilization: Why are pea plants a good subject to be tested concerning inheritance? Explain how self-pollinating plants reproduce? What is the difference between pollination and fertilization in plants? Unit: MENDELIAN GENETICS Mr. Taylor, 2013 Revision No.1 2
*** MENDELIAN GENETICS *** 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: 1. 2. 3. Why is it important that Gregor Mendel chose only one characteristic at a time when studying pea plants? Mendel chose plants that had forms for each of the characteristics he studied. Mendel s plant characteristics that he studied: Result = Plant or HEIGHT Name at least 3 different traits that Gregor Mendel studied in pea plants? Plant SHAPE Why did Mendel choose two characteristics for each traits? Result = or Plant COLOR Why are pea plants a good specimen to study inheritance? Result = or The two forms for each characteristic above are called. Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 3
*** MENDELIAN GENETICS *** 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. Describe what Mendel meant by crosspollination? Describe what a pure-bred trait is and give one example? 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. Cross-pollination in plants: 1. 2. This way, Mendel could have control of his experiments by selecting which pollen would fertilize which plant. Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 4
*** MENDELIAN GENETICS *** *** PARENT GENERATION *** WRINKLED SEEDS ROUND SEEDS Wrinkled seeds *** F1 GENERATION *** 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. Write the result of the F1 generation to the left What do you think happened to the trait for wrinkled seeds? Why did not appear in the F1 generation? Write your reasoning below: 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? What happened to the recessive trait? Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 5
*** MENDELIAN GENETICS *** G. MENDEL S SECOND EXPERIMENT Mendel allowed the F1 or first generation from each of the seven crosses to self-pollinate. *** PARENT GENERATION *** WRINKLED SEEDS ROUND SEEDS 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! No matter which characteristic Mendel investigated, when the F1 generation was allowed to self-pollinate, the recessive trait reappeared. *** F1 GENERATION *** *** F2 GENERATION *** List some traits in your family that have appeared or disappeared from different generations: 1. 2. 3. 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? Unit: MENDEIAN GENETICS Mr. Taylor, 2013 : Revision No.1 6
*** MENDELIAN GENETICS *** II. 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. These sets of instructions are called genes. Review: Why is it important to mate an individual after the F1 generation? Describe the following terms: Genes - Alleles - Describe the importance of a Punnett Square? Genes: Alleles: To mathematically understand Mendel s conclusions it is important to use a tool called a. Punnett Square: Punnett Squares use two sets of alleles. Where do these sets come from? Why type of cell transmit these allelles? 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. Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 7
*** MENDELIAN GENETICS *** 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. Example: 3. B = is a allele (form of gene) for brown eyes 4. b = is any other eye color which is a allele (form of gene) Answer the following questions: Put answers here: If an individual has the genotype of BB or Bb they will have what color eyes? If an individual has the genotype of bb, they will have what color eyes? The prefix hetero means. Therefore, alleles written by [1] capital letter and [1] lower case letter is called. Example: Bb, Aa, Ss, Tt, etc [ ] Define the following terms? Genotype: Allele: Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 8
*** MENDELIAN GENETICS *** 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? 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) Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 9
*** 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: 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 #1: Draw a 4x4 box to setup your monohybrid cross. Describe what a Punnett Square is used for? Are recessive alleles assigned lowercased or uppercase letters? Why? Define monohybrid cross? Step #2: Step #3: Step #4: What % of the parent s offspring will have blue eyes (bb)? % Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 10
*** PUNNETT SQUARES *** Interesting fact: Good ideas are often overlooked or misunderstood when they first appear. This was the fate of Gregor Mendel s ideas. In 1865, he published his findings for the scientific community. Unfortunately, his work didn t get much attention. It wasn t until after his death, more than 30 years later, that Mendel finally got the recognition he deserved. Once Mendel s ideas were rediscovered and understood, the door was opened to modern genetics. Practicing and Applying Concepts Predict the offspring from a cross between two hybrid tall pea plants. (T- tall, t-short) 6. What is the genotype for a hybrid tall plant? 7. Use the Punnett Square below to determine the genotypes for the offspring. 8. What is the probability that the plant would be tall? 9. What is the probability that the plant would be short? 10. If you planted 100 seeds from this cross, how many would you expect to be tall? Practicing and Applying Concepts The Punnett square at the left shows the possible combinations of alleles for fur color in rabbits. Black fur, B, is dominant over white fur, b. Given the combinations shown, what are the genotypes of the parents? Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 11
*** PUNNETT SQUARES *** Use the chart above to answer the following questions based on the given genotypes of different alleles. 1. Offspring s alleles: What is the cat s phenotype if the genotype is [HH, Tt, nn]? 2. Write the genotype of a short haired, stripeless cat with no color in its tail? 3. If a heterozygote male cat mated with a homozygote long hair cat, what is the probability that their offspring will be short hair? Use the Punnett square below! 4. Is it possible for an offspring to have long hair if both it s parents had short hair? Explain? Unit: MENDEIAN GENETICS Mr. Taylor, 2013 Revision No.1 12
PLEASE FOLLOW ME AND STAY UPDATE ON ANY NEW PRODUCTS. There is an available Interactive PowerPoint that correlates to this notepacket. Copy and paste the following link into your webbrowser. http://www.teacherspayteachers.com/product/gregor- Mendel-and-Punnett-Squares-Interactive-PowerPoint-905059 THANK YOU FOR Y OUR SUPPORT! Mr. TAYLOR