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INTRODUCTION TO GENETICS FROM PROTEINS TO MENDEL Rosa Macaya 16/Maig/201 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.1. Should we have our four child? INTRODUCTION AND RATIONALE A fictional story is used to introduce the topic in order to relate our topic with everyday life. The text has been written using grammar structures according to the age and knowledge of the students. They are aged 17-18 and will probably have quite a good English background. As the text is quite long it is divided into three parts, and the activities are also split. The activities progress in complexity, moving from LOT to HOT. Students are not expected to understand everything the first time they listen. The overall aim of the activity is for students to begin to question the role of genes, to get them interested in why the situation arises, and what might be able to be done about it. Lesson Length: 90 minutes Activity 1.1. Resources: Worksheet 1/audio I Listen and tick Give out Worksheet 1 and tell students to listen to the text and tick the words they hear. Give students time to check what they have ticked in pairs before moving to the next part. Tell students they will be able to check their answers later. II Family tree Focus students’ attention on Part II and get them to fill in the family tree. Rosa Macaya IES Pobla de Segur 2 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.1. Should we have our four child? Give students time to check in pairs what they have written before moving to the next part. Tell students they will be able to check their answers later. III Identify the problem. Get students to listen and then complete the sentence starters Give students time to check in pairs what they have written. Tell students they will be able to check their answers later. Activity 1.2. Resources: Worksheets 1&2/audio For each part, students listen to the text and fill in the gaps. They also add to their notes on Worksheet 1. After each section, they check in pairs. Check the answers in plenary after each section/at the end of the three parts. Help students with key vocabulary (suggest which words here). Give students the complete text at the end. Rosa Macaya IES Pobla de Segur 3 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.1. Should we have our four child? Activity 1.1. KEY I. Listen to the story and tick the words you hear HAPPINESS TEA INFUSION UNHAPINESS BLOOD TRANSFUSION BAD LUCK BLOODY GOOD LUCK BLOODINFUSION UNLUCKY BLEEDING PARENTS GRANDPARENTS OLDEST DEAD ELDEST ALIVE II. Listen to the story and take notes to draw a family tree. III. Listen to the story and try to find out what the problem is. Rosa Macaya IES Pobla de Segur 4 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.1. Should we have our four child? Activity 1.2. KEY 1.2.1. Listen to the story and find out the missing words. Help yourself from the words given in activity 1.1. Should we have a fourth child??? When I was young I always dreamt about having children. I’d never thought that anything bad could happen to me. Even though my brother’s dead. He was really unlucky. Yes, he always had bad luck… My parents suffered so much; it was tough having to think about every little thing that Paul did. They couldn’t live in peace all his life. Phone calls from the school saying he was bleeding. Mum running to take him to hospital, blood infusions plus all day-to-day stuff. It was all quite normal to me. I grew up with all of this. But, even so, I did not expect something like this to happen to me, to my children. Nobody told me that, nobody asked when I first got pregnant. There was happiness all around, even from my parents. They were so excited about becoming grandparents; they didn’t tell me that there was any possibility of there being any problem with my child. But they didn’t tell me because they did not know the truth about their own son. Poor Paul. He died years ago from AIDS, something to be ashamed of. It wasn’t Paul’s fault. Poor Paul… all his short life affected by what he had inherited. He didn’t choose to die; death found him… got into somebody’s blood. Yes, somebody’s blood. How unlucky was that! Poor Paul… But nobody told me that my own kids could have the same problem as my eldest brother, my beloved brother. Not even the doctors told me anything. They didn’t ask me about my family background. Rosa Macaya IES Pobla de Segur 5 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.1. Should we have our four child? (Part I (1’46’’)28 lines) KEY 1.2.2. Listen to the story. Fill in the gaps and complete the family tree you drew in activity 1.1. So I had my first child. We all felt so happy. And my second, the lovely Helen, and no problem either. But our luck seemed to run out when my youngest son was born. Just arrived in the world and he started to suffer. His birth was very traumatic. I lost a lot of blood, hours and hours and my poor baby was still bleeding. My mother prayed. I was scared; I could not see him until days later. My husband could, but he didn’t tell me anything. Well, I don’t think he knew what to say. When our son was diagnosed with “haemophilia” I didn’t know what it meant. In hospital we were asked about our family background and then I discovered the truth about Paul. I couldn’t understand why my parents hadn’t told me the truth about Paul’s illness, even about his death. But I don’t think they were sure about anything. I feel sorry for them now, but then I was very disappointed and I blamed them for my baby’s disease. If had known about this before, then certainly I wouldn’t have had the kid. But we did not know anything! (Part II, (1’13’’)15 lines) KEY 1.2.3. Listen to the story. Fill in the gaps and write two sentences summarising the story. It took a while for us to understand haemophilia. With a lot of help from all the hospital staff we learnt to cope with it and how to bring up our haemophilic child. Things have changed a lot, new products have been discovered and I hope my youngest child’s life will be easier than his uncle’s. Now, our Tom is already 6 years old and he seems to be controlling his bleeding episodes. I don’t know if I am a carrier or not. Neither does my husband. Though everything points to the gene coming from my family. I have learnt a lot about haemophilia. If only my parents had known more…, but I don’t think that it was their fault. They didn’t know anything and the doctors didn’t tell them anything; they probably thought they wouldn’t understand. It is pity to live in such ignorance! Always Rosa Macaya IES Pobla de Segur 6 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.1. Should we have our four child? believing that life is a kind of fate… But I don’t want to live like that. I’d like to have a fourth child and I want to know what the chances are of having a “healthy” child in spite of my gene history. I have heard about being able to find out, but I am not sure. Science should be there to help to fight against our “bad” genes, shouldn’t it? (Part III, (1’15’’) 19 lines) Rosa Macaya IES Pobla de Segur 7 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.1. Should we have our four child? TAPESCRIPT SHOULD WE HAVE A FOURTH CHILD??? When I was young I always dreamt about having children. I’d never thought that anything bad could happen to me. Even though my brother’s dead. He was really unlucky. Yes, he always had bad luck… My parents suffered so much; it was tough having to think about every little thing that Paul did. They couldn’t live in peace all his life. Phone calls from the school saying he was bleeding. Mum running to take him to hospital, blood infusions plus all day-to-day stuff. It was all quite normal to me. I grew up with all of this. But, even so, I did not expect something like this to happen to me, to my children. Nobody told me that, nobody asked when I first got pregnant. There was happiness all around, even from my parents. They were so excited about becoming grandparents; they didn’t tell me that there was any possibility of there being any problem with my child. But they didn’t tell me because they did not know the truth about their own son. Poor Paul. He died years ago from AIDS, something to be ashamed of. It wasn’t Paul’s fault. Poor Paul… all his short life affected by what he had inherited. He didn’t choose to die; death found him… got into somebody’s blood. Yes, somebody’s blood. How unlucky was that! Poor Paul… But nobody told me that my own kids could have the same problem as my eldest brother, my beloved brother. Not even the doctors told me anything. They didn’t ask me about my family background. (Part I (1’46’’)28 lines) So I had my first child. We all felt so happy. And my second, the lovely Helen, and no problem either. But our luck seemed to run out when my youngest son was born. Just arrived in the world and he started to suffer. His birth was very traumatic. I lost a lot of blood, hours and hours and my poor baby was still bleeding. My mother prayed. I was scared; I could not see him until days later. My husband could, but he didn’t tell me anything. Well, I don’t think he knew what to say. When our son was diagnosed with “haemophilia” I didn’t know what it meant. In hospital we were asked about our family background and then I discovered the truth about Paul. I couldn’t understand why my parents hadn’t told me the truth about Paul’s illness, even about his death. But I don’t Rosa Macaya IES Pobla de Segur 8 INTRODUCTION TO GENETICS From Proteins to Mendel Unit 1 Teaching Notes Lesson 1.1. Should we have our four child? think they were sure about anything. I feel sorry for them now, but then I was very disappointed and I blamed them for my baby’s disease. If had known about this before, then certainly I wouldn’t have had the kid. But we did not know anything! (Part II, (1’13’’)15 lines) It took a while for us to understand haemophilia. With a lot of help from all the hospital staff we learnt to cope with it and how to bring up our haemophilic child. Things have changed a lot, new products have been discovered and I hope my youngest child’s life will be easier than his uncle’s. Now, our Tom is already 6 years old and he seems to be controlling his bleeding episodes. I don’t know if I am a carrier or not. Neither does my husband. Though everything points to the gene coming from my family. I have learnt a lot about haemophilia. If only my parents had known more…, but I don’t think that it was their fault. They didn’t know anything and the doctors didn’t tell them anything; they probably thought they wouldn’t understand. It is pity to live in such ignorance! Always believing that life is a kind of fate… But I don’t want to live like that. I’d like to have a fourth child and I want to know what the chances are of having a “healthy” child in spite of my gene history. I have heard about being able to find out, but I am not sure. Science should be there to help to fight against our “bad” genes, shouldn’t it? (Part III, (1’15’ Rosa Macaya IES Pobla de Segur 9 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.2. Making posters! INFORMATION AND RATIONALE This lesson’s aim is to give more information about the family in order to work a little more with the pedigree chart and about the family background. The second activity objective is to learn a bit about the two illnesses cited in the story. Students will learn more specific vocabulary (language of and language for) which it will be needed for the next lesson’s activities. The third aim is to practice orally presentations and peer evaluation. Lesson Length: 2 hours Activity 1.2.1. Working the pedigree chart Resources: Student worksheet Tell students how to read a pedigree chart and the meaning of the figures. (round: females/square: males). When a genetic disease is present it should be marked, ie a different colour. So in this pedigree students colour PAUL and TOM in red. Students read the text and put the names of the family members. Compare the information you have written on the pedigree chart in activity 1.1.1. Colour in a different colour the members with haemophilia. Activity 1.2.2. Making a “mind map” poster Resources: Student worksheet and card, colours, pictures, (material to make a poster…) There are two descriptive texts blocs: one about haemophilia and the other about AIDS. The information about each disease is divided into different parts (causes, Rosa Macaya IES Pobla de Segur 10 INTRODUCTION TO GENETICS From Proteins to Mendel Unit 1 Teaching Notes Lesson 1.2. Making posters! symptoms, types, therapy…). This information has to be summarized and put in a mind map. Procedure: Teacher divides up the students into two groups A and B. Working alone, students in Group A read the information about haemophilia and highlight the main information. Then students in groups make a poster with drawings, pictures and short texts describing the information in the text. Group B will do the same but about AIDS. When the posters are finished put them on the wall. Each group will explain about the disease they have worked out. All members have to speak. At the end each group will give an oral feedback (peer evaluation) following these criteria: • Positive point’s poster layout, clearly explanations, voice, eye contact… • To improve: Rosa Macaya “ “ “ “ “ ” “ ” “ ” “ IES Pobla de Segur 11 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.2. Making posters! Activity 1.2.1. KEY Read the following text and put the names of the family members. Compare the information you have written on the pedigree chart in activity 1.1.1. Colour in a different colour the members with haemophilia. Mrs Ann Drinkwater, born Pennymann, is a 38 years old woman with a family history of haemophilia A. She had got a five years older brother, Paul, who died 10 years ago after getting AIDS from a contamined plasma infusion. She does not have further information about other members of her family. Mrs Drinkwater’s husband, John is 40 years old and there are not haemophilia traits in his family. They have three children, the eldest is 12 years old called Matthew, Helen is 10. Both of them are not haemophilic. The youngest, Tom is 6 years old and he is haemophilic. Ann and John Drinkwater would like to have a fourth child and they have applied to a Genetic Cabinet to know the probability of having another child with the disease and if there is a possibility to avoid 100% sure that the inheritance of the haemophilia using Genetic Therapy. Rosa Macaya IES Pobla de Segur 12 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.2. Making posters! Activity 1.2.2. Making a poster Information about Haemophilia • Causes Haemophilia is a sex-linked disorder. Its gene is in chromosome sexual X. Since males (XY) have only one X chromosome, so only one copy of the gene is placed in this chromosome, if the gene is present, then they will be affected with the disease. Females have two X chromosome (XX) and only will have the disease when they have the gene in both (rare). The probability of a woman having the disease is very low, though possible. That would happen if both father and mother had the affected haemophilic gene. Frequently females are only carriers because this gene is recessive in front of the normal gene. That is why they have the ability to pass the gene on to their offspring but are not affected with the illness themselves. • Types There are two types of haemophilia, A and B. Haemophilia A involves a mutation in the factor (protein) VIII blood clotting factor gene and haemophilia B involves a mutation in the factor IX blood clotting factor gene. Both mutations do not let the process of blood clotting happen, as it normally should. • Symptoms Include internal bleeding, blood in stool and urine, frequent nosebleeds, easy bruising, and bleeding into muscles and joints that lead to chronic arthritis; bleeding in the rain. External bleeding could appear if the skin is broken by a scrape, cut or abrasion. • Therapy There is no cure for haemophilia, but it can be controlled with regular injections of the deficient clotting factor, i.e., factor VIII in haemophilia A. In western countries, common standards of care fall into two categories: prophylaxis or on-demand. The first one involves the infusion of clotting Rosa Macaya IES Pobla de Segur 13 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.2. Making posters! factor in order to keep clotting levels sufficiently high to prevent spontaneous bleeding episodes. On-demand treatment involves treating bleeding episodes once they arise. • Collateral problems related to haemophilia therapy As a direct result of the contamination of the blood supply in the late 1970’s and early 80’s with virologic agents such as HIV (Human Immunodeficiency Virus) and Hepatitis new methods were developed in the production of clotting factor products. The initial response was to heat treat (pasteurize) plasma-derived concentrate, followed by the development of monoclonal factor concentrates grown to inactivate any viral agents. More recently, recombinant factors products (which are typically cultured in Chinese hamster ovaries and involve little, if any contact with human plasma products) have become available and are widely used in wealthier western countries. These products are quite safe but also very expensive and not usually available in developing countries and sometimes are even difficult to find in developing countries. Rosa Macaya IES Pobla de Segur 14 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.2. Making posters! Information about AIDS • What does “AIDS” mean? AIDS stands for Acquired Immune Deficiency Syndrome: Acquired means you can get infected with it. Immune Deficiency means a weakness in the body’s system that fights diseases. Syndrome means a group of health problems that make up a disease. • Causes AIDS is caused by a virus called HIV, the Human Immunodeficiency Virus. If you get infected with HIV, your body will try to fight the infection. It will make “antibodies,” special molecules to fight HIV. A blood test for HIV looks for these antibodies. If you have them in your blood, it means that you have HIV infection. People who have the HIV antibodies are called “HIV-Positive.” Fact Sheet 102 has more information on HIV testing. Being HIV-positive, or having HIV disease, is not the same as having AIDS. Many people are HIV-positive but don’t get sick for many years. As HIV disease continues, it slowly wears down the immune system. Viruses, parasites, fungi and bacteria that usually don’t cause any problems can make you very sick if your immune system is damaged. These are called “opportunistic infections.” • How do you get AIDS? You don’t actually “get” AIDS. You might get infected with HIV, and later you might develop AIDS. You can get infected with HIV from anyone who’s infected, even if they don’t look sick and even if they haven’t tested HIVRosa Macaya IES Pobla de Segur 15 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.2. Making posters! positive yet. The blood, vaginal fluid, semen, and breast milk of people infected with HIV has enough of the virus in it to infect other people. Most people get the HIV virus by: having sex with an infected person. sharing a needle (shooting drugs) with someone who’s infected. being born when their mother is infected, or drinking the breast milk of an infected woman. Getting an infusion of infected blood used to be a way people got AIDS, but now the blood supply is screened very carefully and the risk is extremely. Rosa Macaya IES Pobla de Segur 16 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.3. Making live possible...from DNA to Proteins INTRODUCTION AND RATIONALE The main aim of this lesson is for students to be able to apply their previous knowledge about Molecular Genetics to understand the causes of haemophilia. Students already know from lesson 2 more about the disease and they have to find out how it could happen from a deeper molecular point of view (DNA mutation) in order to link the facts with Mendelian Genetics later on. The activities progress from general and theoretical facts to the haemophilia as a consequence of a mutation. The used of the Scientific Method is an aim in this lesson as well. Lesson Length: 3 hours Resources: Power Point: Molecular Genetics and Student Worksheet Pre-Activity: Power Point to review Molecular Genetics: the topics and some examples. Try to ENGAGE students’ interest through some interactive tasks (asking guessing questions…) Activity 3.1. and 3.2. Give students the worksheets Give students time to revise the mind map about “The Dogma Central of Molecular Biology, and do the exercises. Check the answers in plenary. Rosa Macaya IES Pobla de Segur 17 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.3. Making live possible...from DNA to Proteins Activity 3.3. Power Point/Sheet to explain about Scientific Method. Try to ENGAGE students’ interest though some interactive tasks and make sure that they understand what they are doing giving and asking for examples. In plenary explain and then write all the steps of the Scientific Method used to find out a possible cause of haemophilia. Teacher should help students with the sentences used to hypothesize and predict. Rosa Macaya IES Pobla de Segur 18 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.3. Making live possible...from DNA to Proteins Review of Molecular Genetics Activity 1.3.1 Look at the following picture… “The Central Dogma of Molecular Biology: From DNA to RNA to Protein,, Rosa Macaya IES Pobla de Segur 19 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.3. Making live possible...from DNA to Proteins KEY Now………… From the single DNA strand below, write the complementary 5’ .. t a c t a a c g t t t g t a c a a a c c g g a a a t t .. 3’ 3’ .. a t g a t t g c a a a c a t g t t t g g c c t t t a a .. 5’ then write the mRNA mRNA 3’ .. a u g a u u g c a a a c a u g u u u g g c c u u u a a .. 5’ Look at the pictures below and write the correct name in each label Aminoacid, tRNA, Ribosome, mRNA Rosa Macaya IES Pobla de Segur 20 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.3. Making live possible...from DNA to Proteins And now……….. with the help of the Genetic Code Table, translate the RNA nucleotides’ sequence to a polypeptide sequence Met-Ile-Ala-Asn-Met-Phe-Ala-Leu- STOP You have made a protein!!!! Rosa Macaya IES Pobla de Segur 21 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.3. Making live possible...from DNA to Proteins KEY Activity 1.3.2 Mutations What WILL happen IF.... .........we change a pair nucleotides from the DNA strand…. t ac t a a c g t t t g t a c a a a c c g g a a a t g c t . a tg a t t g c a a a c a t g t t t g g c c t t t a c g u State a hypothesis telling what could happen if you write two “aa” instead the two tt. You can start the hypothesis… “If I write aa, in the place of tt then the mRNA will be aa and then the mRNA would be changed and then the protein would be different. Now think a “way”, to prove your hypothesis (Students have to repeat all the process, duplication, transcription and translation) mRNA: aug auu gca uuc aug uuu gcc cuu uaa Protein: Met-Ile-Ala-Phe-Met-Phe-Ala-Leu-STOP Write down the conclusion. If nucleotides’ sequence changes in the DNA strand then this change will carry on during the transcription and the translation. The resultant protein will be a different one. Now, try to do another mutation, in this case try to delete a pair nucleotides from the DNA strand… Predict what will happen…. And prove it! Rosa Macaya IES Pobla de Segur 22 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.3. Making live possible...from DNA to Proteins (Students have to repeat all the process, duplication, transcription and translation) It is an open answer (each student will choose the “mutation”) Rosa Macaya IES Pobla de Segur 23 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.3. Making live possible...from DNA to Proteins KEY Activity 1.3.2. Let’s Scientific Method and to relate Haemophilia (lack of an appropriate protein) and inheritance (DNA). Let’s do all together to write a hypothesis about this relationship and all the steps to prove or reject our hypothesis!! We are going to follow all the steps from the scientific method: 1. Problem – (What are you trying to figure out? Write this in the form of a question.) Why doesn’t haemophiliacs’ clotting process happen as it should? 2. Hypothesis – (What do you think you are going to find out? If the gene of the blood clotting protein is affected by a mutation, the transcription will carry on the error and mRNA will translate a new protein unable to do this function 3. Materials and procedure (List the materials you will use in the experiment.) (In this case it is a theoretical exercise) The students will have to write a “normal DNA sequence” and do all the process: duplication, transcription and translation. Below the same sequence but marking the mutation (some nucleotide changed or deleted). Again, do all the process: duplication, transcription and translation. 4. Results – What did you observe when you performed the experiment? There are two different proteins, the “normal one” from the “normal” DNA strand and the new one from the “mutated” DNA. 5. Conclusion – From what you observed, how would you answer your original question? Haemophilia involves a mutation in the protein blood clotting factor DNA (gene) and this mutation does not let the process of blood clotting happen. Rosa Macaya IES Pobla de Segur 24 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.4. Once upon a time playing with pea plants INTRODUCTION AND RATIONALE The aim is to end the unit and at the same time to introduce to Mendelian Genetics through a text about Mendel. From this text students will gain information about Mendel’s life. This text will also be linked to the start of the next unit. One of the aims of this lesson is to place Mendel in his time and in the History of Biology. Warm-up activity Supplementary Material “Blending Theory” Explain the “beliefs” about how traits were supposed to pass to the offspring before Mendel’s findings (Blending Theory) (paper in supplementary material) Make it clear that Mendel did not know anything about Molecular Genetics. Write or display the following questions for students to discuss: • “Why do you think Mendel is known as the Father or genetics?” (Because he discovered the basic underlying principles of heredity) • “Do you think that using mathematics to work out the data was usual in Mendel’s time? (No, he was the first one to made use to this scientific language) • What do you think Mendel carried out his breeding experiments with pea plants? (Because he could observe inheritance patterns in up two generations a year) • Think and compare how scientific findings are communicate and published today and in Mendel’s time. (Here can be told that today the language of Rosa Macaya IES Pobla de Segur 25 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.4. Once upon a time playing with pea plants science is English and that should help the communication. Remember Mendel published his work in German. Relate this fact with other cases, like Wegener…) Rosa Macaya IES Pobla de Segur 26 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.4. Once upon a time playing with pea plants Lesson Length: 2 hours Resource: Student Worksheet: text, table. Activity 1.4.1. Comprehension text test. Dictionary • Give out Worksheet 1.4. • Divide the class into 3 sections (A, B, C). • Students in Section A receive text A, those in Section B receive text B and those in section C receive text C. • Make Section B a group of stronger students. • Students read their section and fill in the relevant information on their worksheet. • Students discuss their answers within their groups. • Be available to help with vocabulary. • Students make groups of 3 (one A, one B, one C) and orally exchange information to fill in the whole chart. • Check the answers in plenary. Activity 1.4.2. • Students are given worksheet 1.4. • Students work individually to answer the questions referring to their own texts. • Students discuss in groups of three to get answers to all of the questions. • Feedback in plenary. Discussion: Go back to the questions in the warm-up and ask students to add their idea Rosa Macaya IES Pobla de Segur 27 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.4. Once upon a time playing with pea plants KEY Activity 1.4.1 Date of birth Father’s job Grandfather’s job Why did he have to stop studying? Where did he continue his studies? What did he do in Vienna? What plant did Mendel mainly work with? What did he discover about tall plants? What did he discover about short plants? What resulted from crossing tall and short plants? How many plants did he use? How many years did it take? What was his first law called? What was his second law called? How many basis laws of heredity did he uncover? Did he become famous in his life? Why (not)? When did he die? What happened in 1900? Rosa Macaya 22 July 1822 Farmer Gardener Because of financial problems In the monastery of Brunn Studied Zoology, Botany, Chemistry and Physics Pea plants They produced tall and short offspring They only produced short offspring Tall plants Over 30,000 More than 8 The law of segregation The law of independent assortment six No Statistics were unusual at that time and he was not well known enough 6 January 1884 IES Pobla de Segur 28 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 1 Lesson 1.4. Once upon a time playing with pea plants KEY. Activity 1.4.2 Testing the text 1) Gregor Mendel was: a) an English gardener who grew pea plants b) an unknown Central European monk c) an early 20th century Dutch biologist who carried out genetics research 2) Which of the following statements is true about Mendel? a) His discoveries concerning genetic inheritance were accepted by the scientific community b) He believed that genetic traits of parents would usually blend in their children. c) He made statistical analysis in his breeding experiments 3) Mendel believed that the traits of the pea plants are determined by the: a) hereditary units or factors from both parents b) hereditary units or factors from one parent c) health of the plant during the pollination 4) Mendel discovered that: a) short plants produced only short offspring b) tall plants produced only tall offspring c) short plants produced both, tall and short offspring 5) Mendel's law of independent assortment states that: a) each pair of genes is inherited independently of all other pairs. b) each pair of genes is inherited dependently of all other pairs. c) only a gene is inherited independently of all other Rosa Macaya IES Pobla de Segur 29 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.1. Diving into the pool of genetic terminology INTRODUCTION AND RATIONALE The aim of this lesson is to focus on the main concepts of Mendelian Genetics, using a ppt presentation, during which students will be invited to participate, answering questions that the teacher will ask, i.e. giving examples. Prior to this, the hot-seat activity (2.1.1) links the biographies used in lesson 1 to the teacher’s explanations on Mendelian Genetics. Lesson Length: 2 hours Resources: Student Worksheets 2.1.2 & Student Vocab Pronunciation Sheet & Word cards (SM) Activity 2.1.1. Hot Seat An “able” student sits and adopts the role of Mendel and answer questions asked by the rest of students (he/she can have a copy of Mendel’s biography) Students will already have the questions from the last homework from Lesson 1.4. Activity 2.1.2. Genetic World Words Through this activity students consolidate the genetic terminology needed. The activity is divided into four sub-activities, going from easy to more difficult. This activity is a mixture of writing, oral and listening skills. A Vocabulary-phonetics transcription sheet (Supplementary Material) should be given so that students write down (again) the words and their phonetic transcription. a) Word puzzle. Students work on their own. After 5 minutes give them the key. b) Definition Team Game Rosa Macaya IES Pobla de Segur 30 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.1. Diving into the pool of genetic terminology 1. Divide up students into two teams: 1 & 2 2. Give each team a set of 15 words. Give them time to look at them. 3. Teacher reads out the definition and gives students time to find the matching word. 4. Students shout out the answer when they think they know. 5. Each correct answer: 1 point. c) Genetic terminology crossword. Students work on their own. After 5 minutes give them the key. d) Filling in the gaps: students work on their own and then check their answers in pairs before a plenary checking plenary. Each student reads out an answer. Teacher says if it is correct or not. Rosa Macaya IES Pobla de Segur 31 INTRODUCTION TO GENETICS From Proteins to Mendel Unit 2 Teaching Notes Lesson 2.1. Diving into the pool of genetic terminology Activity 2.1.2. a) Warming up! KEY Find the 15 words hidden in the puzzle. R D O U W W V O S G E T O I U H K U G J W J R U M E L I K G G N I R P S F F O G L N E H X E V Q K K H Z S G S D S E H I S T Q Q T J O E Y I I E H H N G F E R G M J E Z S K S R M I E P A M O F P M O O I D E B C Y I T R A P A I M T J K C W S T J H P N G E W O I W A E E P N C D N H M G Q H M C F S L E H E T E R O Z Y G O U S S T R W I D O M I N A N T T Z I N M K W B Q K Z A V I J R E V I V J L K H G Z L I D I N Z E X E P U R E T Q F E D I R B Y H L CHROMOSOME DOMINANT EGG GAMETE GENE HETEROZYGOUS HOMOZYGOUS HYBRID MEIOSIS MITOSIS OFFSPRING PURE RECESSIVE SPERM TRAIT Rosa Macaya IES Pobla de Segur 32 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.1. Diving into the pool of genetic terminology b) Definition Team Game KEY 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 Offspring that are the result of mating between two genetically different kinds of parents (opposite of purebred) The study of gene structure and action and the patterns of inheritance of traits from parent to offspring. This is the branch of science that deals with the inheritance of biological characteristics. A XIX century central European monk scientist who published his ideas about genetics in 1866 but largely went unrecognized until 1900, which was long after his death. He acquired his understanding of genetics mostly through pea plant breeding experiments. A theory that inherited traits blend from generation to generation. Most of the leading scientists in the XIX century accepted it. However, Gregor Mendel proved that it was not correct. Offspring that are the result of mating between genetically similar kinds of parents (the opposite to hybrid) Units of inheritance usually occurring at specific locations or loci, on a chromosome. These units are responsible for hereditary characteristics in plants or animals. Alternate forms of the same gene. Because they are different, their action may result in different expressions of a trait. The genetic makeup of an individual for a trait or for all of his/her inherited traits ( no observable or detectable characteristics) A genotype consisting of two identical alleles of a gene for a particular trait. A genotype consisting of two different alleles of a gene for a particular trait. The observable or detectable characteristics of an individual organism. The detectable expression of a genotype. The general term for an allele that is masked in the phenotype by the presence of another allele (opposite to dominant allele) The general term for an allele that masks the presence of another in the phenotype. Gregor Mendel ‘s principle of genetic of inheritance stating that, for any particular trait, the pair of genes of each parent separate (during meiosis or formation of sex cells) and only one gene from each parent passes on to an offspring. Gregor Mendel’s principle of genetic inheritance stating that that different pair of genes are passed to offspring independently so that new combination of genes, present in neither parent, are possible. In other words, the distribution of one pair of alleles does not influence Rosa Macaya Hybrid Genetics Gregor Mendel Blending theory Purebred Genes Alleles Genotype Homozygous genotype Heterozygous genotype Phenotype Recessive allele Dominant allele Principle of segregation Principle of independent assortment IES Pobla de Segur 33 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.1. Diving into the pool of genetic terminology the distribution of another pair (the genes controlling different traits are inherited independently or one another. c) Genetic Terminology Crossword KEY Across 1. Opposite of recessive: DOMINANT 4. Section of DNA: GENE 5. Rewriting DNA's message: TRANSCRIPTING 7. The first cell: ZIGOT 9. Humans have 23 pairs: CHROMOSOMES Down 2. Different form of a gene: ALLELES 3. Opposite to pure-breeding: HYBRID 4. Combination of alleles: GENOTYPE 6. Proteins Factory: RIBOSOMES 8. Appearance of an organism's trait: PHENOTYPE 10 of 10 words were placed into the puzzle. Rosa Macaya Created by Puzzlemaker at DiscoveryEducation.com IES Pobla de Segur 34 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.1. Diving into the pool of genetic terminology And to end…….. d) Fill in the gaps: choose the correct word KEY 1. Gregor Mendel, the "father of genetics". (Mendel/Darwin) 2. The first hybrid/heterozygous generation is the offspring of a cross between parents that are pure for a given trait. (Hybrid/Herozygous/ filial) 3. The principle of dominances and recessiviness. (blending/dominances) 4. The outward expression or appearance: Phenotype (phenotype/genotype) 5. Cross that involves parents that differ in TWO traits. Dihybrid Cross (dihybrid cross/ Monohybrid cross) 6. The study of heredity: Genetics (heredity/genetics) 7. An alternate form of a gene: Allele (allele/factor) 8. The Principle of Independent Assortment (dependent/independent) 9. Having non identical alleles (not pure; ex. Aa): Heterozygous (heterozygous/homozygous) 10. Having identical alleles (pure, ex. AA): Homozygous (heterozygous/homozygous) 11. Square used to determine probability and results of cross: Punnett (Punnett/Mendel) 12. The allele that is masked or covered up by the dominant allele: recessive (recessive/dominant) 13. The genetic make-up or an organism (Tt): Dominant (recessive/dominant) 14. A cross that involves ONE pair of contrasting traits: Test cross (test cross/ dihybrid cross) Rosa Macaya IES Pobla de Segur 35 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.1. Diving into the pool of genetic terminology 15. The plants Mendel did his studies on: Pea Plants (pea plants/peas plants) 16. The likelihood that an event will happen: Probability (probability/chance) 17. When neither allele is dominant (they are both expressed) Codominant (codominant/recessiviness) 18. Principle of Segregation states that alleles separate when gametes are formed. (segregation/separation) Rosa Macaya IES Pobla de Segur 36 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.2. Swimming with Mendel’s laws INTRODUCTION AND RATIONALE Through different kinds of exercises students study and apply genetics concepts (Mendel’s Laws) they already know from lesson 1. The complexity of the problems grows throughout the lesson, from easy (simple) to more complex exercises (two traits). Students have to translate the statement to the mendelian nomenclature following the steps given. At the end of the lesson, students should be able to solve genetics problems. Also, they have to practise building Punnett squares. As checking will be done orally, language “of” to help students to explain the results will be given as scaffolding. (Supplementary material: results sentences) Lesson Length: 2 hours Resources: Student Worksheet with the exercises & How to solve genetics problems (SM) & Results sentences Procedure: Teacher gives out Worksheet 2.2. with the problems and gives students time to solve the problems individually. Teacher provides help if necessary. The exercises will be checked orally later in plenary. Rosa Macaya IES Pobla de Segur 37 INTRODUCTION TO GENETICS From Proteins to Mendel Unit 2 Teaching Notes Lesson 2.2. Swimming with Mendel’s laws Activity 2.2.1. Simple Genetics Practice Exercises KEY 1. For each genotype, indicate whether it is heterozygous (HE) or homozygous (HO) AA HO Bb HE Cc HE_ Dd HE Ee HE ff HO GG HO HH HO Ii HE Jj HE kk HO Ll HE Mm HE nn HO OO HO Pp HO 2. For each of the genotypes below, determine the phenotype. Purple flowers are dominant to white flowers Brown eyes are dominant to blue eyes PP ___PURPLE___ Pp ___PURPLE___ pp ___WHITE___ BB ___BROWN___ Bb ___BROWN___ bb ___BLUE___ Round seeds are dominant to wrinkled Short tails are recessive (long tails dominant) RR ___ROUND___ Rr ___ROUND___ rr ___WRINKLED___ TT ___LONG TAILS___ Tt ___LONG TAILS___ tt ___SHORT TAILS___ 3. For each phenotype, list the genotypes. (Remember to use the letter of the dominant trait) Straight hair is dominant to curly. Pointed heads are dominant to round heads. ___SS___ straight ___Ss___ straight ___ss___ curly ___PP___ pointed ___Pp___ pointed ___pp___ round Rosa Macaya IES Pobla de Segur 38 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.2. Swimming with Mendel’s laws 4. Set up the square for each of the crosses listed below. The trait being studied is round seeds (dominant) and wrinkled seeds (recessive) What percentage of the offspring will be round? 50% Rr Rr rr rr Rr x Rr RR rR Rr rr What percentage of the offspring will be round? 75% RR x Rr RR RR Rr Rr What percentage of the offspring will be round? 100 % Rr x rr Practice with Crosses. 5. A TT (tall) plant is crossed with a tt (short plant).What percentage of the offspring will be tall? Cross: TT x tt: 100% will be tall 6. A Tt plant is crossed with a Tt plant. What percentage of the offspring will be short? Cross: Tt x Tt: 25% will be short 7. A heterozygous round seeded plant (Rr) is crossed with a homozygous round seeded plant (RR). What percentage of the offspring will be homozygous (RR)? Cross: Rr x RR: 50% will be homozygous Rosa Macaya IES Pobla de Segur 39 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.2. Swimming with Mendel’s laws 8. A homozygous round seeded plant is crossed with a homozygous wrinkled seeded plant. What are the genotypes of the parents? The parents’ genotype is: RR x rr What percentage of the offspring will also be homozygous? None homozygous offspring 0% 9. In pea plants purple flowers are dominant to white flowers. If two white flowered plants are crossed, what percentage of their offspring will be white flowered? PP: purple pp: white pp x pp (white x white) 100 % will be white 10. A white flowered plant is crossed with a plant that is heterozygous for the trait. What percentage of the offspring will have purple flowers? Pp: (purple) Pp x pp = 50 % of the offspring will be purple pp: (white) ___________ 11. Two plants, both heterozygous for the gene that controls flower colour are crossed. What percentage of their offspring will have purple flowers? Cross: Pp x Pp : 75 % will have purple flowers What percentage will have white flowers? 25 % will have white flowers 12. In guinea pigs, the allele for short hair is dominant. What genotype would a heterozygous short haired guinea pig have? S = short hair A heterozygous guinea pig will have Ss genotype S = long hair What genotype would a pure breeding short haired guinea pig have? SS What genotype would a long haired guinea pig have? S 13. Show the cross for a pure breeding short haired guinea pig and a long haired guinea pig Rosa Macaya IES Pobla de Segur 40 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.2. Swimming with Mendel’s laws S S s sS sS s sS sS Cross: P: F1: SS x ss Ss What percentage of the offspring will have short hair? 0 % 14. Show the cross for two heterozygous guinea pigs. S s S SS Ss s sS ss Cross: P: F1: Ss x Ss SS Ss ss What percentage of the offspring will have short hair? 75 % What percentage of the offspring will have long hair? 25% 15.Two short haired guinea pigs are mated several times. Out of 100 offspring, 25 of them have long hair. What are the probable genotypes of the parents? _Ss_ x _Ss_ Show the cross to prove it! Rosa Macaya IES Pobla de Segur 41 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.2. Swimming with Mendel’s laws S s Cross: S SS Ss s sS ss P: Ss x Ss Gametes S s S s F1: SS Ss sS ss Rosa Macaya IES Pobla de Segur 42 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.2. Swimming with Mendel’s laws Activity 2.2.2. Two traits genetics crosses KEY In rabbits, grey hair is dominant to white hair. Also in rabbits, black eyes are dominant to red eyes. GG = grey hair BB = black eyes Gg = grey hair Bb = black eyes gg = white hair bb = red eyes These letters represent the genotypes of the rabbits: 1. What are the phenotypes (descriptions) of rabbits that have the following genotypes? Ggbb _Grey hair and red eyes_ ggBB _White hair and black eyes_ ggbb _White hair and red eyes_ GgBb _Grey hair and black eyes_ 2. A male rabbit with the genotype GGbb is crossed with a female rabbit with the genotype ggBb the square is set up below. Fill it out and determine the phenotypes and proportions in the offspring. gB gB gb gb Gb gGBb gGBb gGbb gGbb Gb gGBb gGBb gGbb gGbb Gb gGBb gGBb gGbb gGbb Gb gGBb gGBb gGbb gGbb How many out of 16 have grey fur and black eyes? 8/16 Rosa Macaya IES Pobla de Segur 43 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.2. Swimming with Mendel’s laws How many out of 16 have grey fur and red eyes? 8/16 How many out of 16 have white fur and black eyes? 0 How many out of 16 have white fur and red eyes? 0 3. A male rabbit has the genotype GgBb. Determine the gametes produced by this rabbit (the sperm would have these combinations of alleles) Hint: there are 4 combinations. GgBb: GB Gb gB gb (four different gametes) 4. A female rabbit has the genotype ggBb. Determine the gametes (eggs) produced by this rabbit. ggBb: gB gb gB gb (two different gametes) 5. Use the gametes from 4 and 5 to set up the punnet square below. Put the female's gametes on the top and the male's gametes down the side. Then fill out the square and determine what kind of offspring would be produced from this cross and in what proportion. GB Gb gB gb gB GgBB GgbB ggBB ggbB gb GgBb Ggbb ggBb ggbb GgBB: Grey fur and black eyes: 3/8 Ggbb: Grey fur and red eyes: 1/8 ggBB: White fur and black eyes: 3/8 ggbb: White fur and red eyes: 1/8 Rosa Macaya IES Pobla de Segur 44 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.3. Swinging with Mendel’s laws exceptions INTRODUCTION AND RATIONALE In this lesson students will practise the non-mendelian patterns of inheritance such as codominance and intermediate expression, multiple alleles, sex determination and sex-linked traits. Although the theoretical background has been already explain through a ppt presentation, students can read a short summary of the content before the exercises. Through these problems and questions students will consolidate the way to solve and deepen their understanding of content and English knowledge. The teacher should tell the students that these points are necessary to end the project and to have background in order to write the report answering Mrs Drinkwater’s question. As checking will be done orally, language “of” to help students to explain the results will be given as scaffolding. (Supplementary material: results sentences) Lesson Length: 3 hours Resources: Student Worksheet with the exercises & How to solve genetics problems (SM) & Results sentences (already given in lesson 2) Procedure: Teacher gives out Worksheet 2.3. with the problems and gives students time to solve the problems individually. Refer students to the text above each part to give them extra support to complete the tasks. Teacher provides help if necessary. The exercises will be checked orally later in plenary. Rosa Macaya IES Pobla de Segur 45 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.3. Swinging with Mendel’s laws exceptions Activity 2.3.1 Codominance, Intermediate Expression and Multiple Allele If there are only two alleles involved in determining the phenotype of a certain trait, but there are three possible phenotypes, then the inheritance of the trait illustrates either incomplete dominance or codominance. The incomplete dominance is also known as intermediate expression, and the phenotype is shown as a blend of the parental phenotypes. Codominance phenotype shows both traits, ie. From a black and white, the offspring phenotype is black with white spots. KEY 1. Practice setting up keys for the phenotypes listed in each set. Remember that the "medium" trait must always be heterozygous. a) Birds can be blue, white, or white with dark-blue feathers. Blue BB White WW Blue-tipped: BW b) Flowers can be white, pink, or red. Red: CRCR White: CWCW Pink: CRCW c) A can have curly hair, spiked hair, or a mix of both curly and spiked. (H=hair) Curly Hair HCHC d) A Spiked Hair HSHS Mix (curly&spiked) Hair HCHS can be tall, medium, or short. (S=size) Tall: STST Medium: STSS Short: SSSS Rosa Macaya IES Pobla de Segur 46 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.3. Swinging with Mendel’s laws exceptions e) A can be spotted, black, or white. (colour) Black: CBCB White: CWCW Spotted: CBCW 2. Now, can you figure out in the above list, which of the examples represent codominant traits and which are incomplete. Codominant: _c,e_ Incompletely Dominant: _a, b, d_ When there are 4 or more possible phenotypes for a trait, then more than 2 alleles for that trait must exist in the population but individuals have only two of those alleles. That happens because individuals have only two biological parents. We inherit half of our genes (alleles) from the mother and the other half from the father, so we cannot have more than two alleles for every trait in our phenotype. An example of multiple allele inheritance is human blood type. Blood type exists as four possible phenotypes: A, B, AB, and O. there are 3 alleles for the gene that determines blood type. The allele for O (i) is recessive to the alleles for A and B. The alleles for A and B are codominant. The alleles are noted as i, IA and IB 3. Mrs. Drinkwater is blood type A and her mother is 0. Her children are o, B and A. Find out what Mr Drinkwater’s blood group could be. If Mrs Drinkwater’s mother is o, her genotype is ii and we can state that Mrs. A Drinkwater’s genotype is I i. Children’s phenotypes: 0 A B P: IAi x ¿? F1: ii // iIA or IAIA // iIB or IBIB With this information we can state that the father could be B B B B B A (genotype: I I or I i) or AB (genotype I I ) Rosa Macaya IES Pobla de Segur 47 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.3. Swinging with Mendel’s laws exceptions Activity 2.2.3. Genetics of Sex Determination In humans the genetic determination of sexual identity involves chromosomes. Humans have 46 chromosomes, 44 of these chromosomes pair together to make 22 pairs of homologous chromosomes (autosomes); the other 2 chromosomes are different, because they are involved in determining the sex. They are called sex chromosomes (XX/XY). Males have an X and a Y chromosome (XY), and females have two X chromosomes (XX). It is known that it is the presence of the Y chromosome that makes the individual male. Your knowledge of meiosis and fertilization provides the basis for understanding the inheritance of X and Y chromosomes. During meiosis in a female, the two X-chromosomes separate, so each egg has a single X-chromosome. In males, even though the X and the Y-chromosomes are very different, they can nevertheless pair with each other and separate from each other during meiosis. This means that males produce two kinds of sperm; half have an X chromosome and half have a Y chromosome. KEY a) What will be the sex of a child produced when an egg is fertilized by a sperm that has a Y chromosome? Male What type of sperm must fertilize an egg to result in a female child? A sperm that has an X chromosome b) Draw a Punnett Square which shows the inheritance of the sex chromosomes. Use X to indicate an egg or sperm with an X chromosome and Y to indicate a sperm with a Y chromosome. Rosa Macaya IES Pobla de Segur 48 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.3. Swinging with Mendel’s laws exceptions X Y X XX XY X XX XY c) Based on this Punnett Square, what percent of children would you expect to be male? MALE: 50% FEMALE: 50% Activity 2.2.4. Sex-linked Traits In humans, the X chromosome carries some genes that are not found in the Y chromosome. Inheritance of the phenotypic traits determined by the genes located in these chromosomes is therefore linked to the sex of the person. The X chromosome carries other genes which are not associated with determination of sex. One of these genes codes for a protein called blood clotting factor. Mutations can occur in this gene resulting in a blood protein that cannot clot the blood properly. This disease is known as haemophilia. Haemophilia Notation: XH chromosome with normal clot factor and Xh KEY In humans, haemophilia is a sex linked trait. Females can be normal, carriers, or have the disease. Males will either have the disease or not (but they won’t ever be carriers) Rosa Macaya IES Pobla de Segur 49 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.3. Swinging with Mendel’s laws exceptions Female normal: XHXH Female carrier: XhX Female haemophiliac: XhXh Male normal: XY Male haemophiliac: XhY Show the cross of a man who has haemophilia with a woman who is a carrier. XhY P: Gametes: X F1 : h x XhXH Xh XH Y XhXh XHXh XhY Xh Y Xh XhXh XhY XH XHXh XHY XH Y What is the probability that their children will have the disease? 50% probability of having a haemophilic girl and the same probability if it is a boy A woman who is a carrier marries a normal man. Show the cross. What is the probability that their children will have haemophilia? What sex will a child in the family with haemophilia be? Rosa Macaya IES Pobla de Segur 50 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.3. Swinging with Mendel’s laws exceptions H Woman genotype: X X h H Man genotype: X Y Phenotype: normal XHXh x P: F1 : Phenotype: normal XHXH XHY XH Y XhXH XhY Probability of having a haemophilic SON 50% from the male children. No GIRLS suffered from haemophilia, so 0% for female children. A woman who has haemophilia marries a normal man. How many of their children will have haemophilia, and what is their sex? h Woman genotype: X X H Man genotype: X Y P: F1 : h Phenotype: haemophilic Phenotype: normal XhXh x XHY XhXH XhY XhXH XhY All their male children will be haemophilic. Rosa Macaya IES Pobla de Segur 51 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.4. Let’s have children!...and something else INTRODUCTION AND RATIONALE The aim of the last part of the project is for students to apply most of the knowledge they have gained during the project. It includes a game in which students simulate the “production” of children with certain traits using chromosomes with samples of all kinds of inheritance patterns done in prior lessons. Students then revisit the question posed by Mrs Drinkwater at the beginning of the project. Again, by using all their knowledge, the students write a report to answer her question. Students are asked to show how they are able to make use of the content they have acquired, applying different skills. As a final activity it is also an assessment activity where the whole content has to be used. To finish the project, there is an oral discussion on science & technology & society. The overall aim of these activities is to consolidate all the content and the use of the target language in a very integrated task and close the project as a loop. Lesson Length: 3-4 hours Resources: Student Worksheets 2.4.1 Student Vocab Pronunciation Sheet Set of 4X2 chromosomes for each student Sheet “How to write a genetic Report” and the sheet “How to create a pedigree chart” Previous Students’ Worksheet to review. Access to the internet or books. PP Presentation (Let’s have children, in SM) Rosa Macaya IES Pobla de Segur 52 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.4. Let’s have children!...and something else Activity 2.4.1. LET’S HAVE CHILDREN! What will our children look like? Procedure Students work in pairs. They follow the instructions on the student’s worksheet (say which number worksheet it is) Analyse the results in plenary: students read out the results and explain the conclusions they have reached. Pick out some of the student’s opinions about their results Help them to summarize the conclusions and focus them on the main goals, for instance the role of chance in heredity, the importance of sexual reproduction, the independence of the events … Activity 2.4.2. Genetic Report Procedure Students work in groups of 3-4 students. Teacher gives each group a sheet with the instructions saying what the report should include (Supplementary Material “How to write the Genetic Report). PART I: Students will probably need to re read the story about the Drinkwater family. They can look at the pedigree done in lesson 1.2. and from that and with the help of the sheet “how to create a pedigree chart” they can create the new one. This pedigree has to show: Rosa Macaya IES Pobla de Segur 53 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.4. Let’s have children!...and something else All family members mentioned All affected individuals All known carriers and suspected carriers. PART II: Students use the questions on the sheet to guide them PART III: In order to complete this section the student can revise the poster they did in lesson 1.2. Explain how Haemophilia is inherited and what a sex-linked trait is Explain the difference between haemophilia A and haemophilia B* Explain the signs and symptoms of haemophilia Explain the treatment options for haemophilia, including future treatments being researched (hypothetical) or genetic screening… Each group writes a genetic report for the Drinkwater family When the report is finished students share in plenary their report. Teacher collects in the reports to check them and give feedback. (To continue this genetic cabinet feedback a further discussion about if sex selection should or should not be recommended. Students will/should be able to make decisions on sex selection cases, rationalize their decision/choices on sex selection and understand the ethical/moral implications of their decisions.) KEY .. Part II: Paragraph about the Drinkwater Family's Haemophilia Explain who has the disorder and who does not Mrs. Drinkwater’s dead brother, Paul Pennymann and her youngest son, Tom Drinkwater Explain who in the family is a carrier and who could be a carrier Rosa Macaya IES Pobla de Segur 54 INTRODUCTION TO GENETICS From Proteins to Mendel Teaching Notes Unit 2 Lesson 2.4. Let’s have children!...and something else Mother Pennymann, Mrs Drinkwater. Mrs. Drinkwater’s daughter could be a carrier. Explain the risk of the next child having the disorder or being a carrier of the disorder (a Punnett square may be used to help explain this section) If the next child is a girl, she has a 50% probability of being a carrier. If boy, 50 % probability of being a sufferer What chromosome is the mutation is located in? (chromosome X) What protein is affected by the mutation? (Blood clotting protein) Activity 2.4.3 Role Play game: Let’s discuss! Procedure: Divide the class into two groups. Give out worksheet no. XXX Designate one group as for and one group as against. Give the groups time to think of ideas and note them down. Give students the sentence banks to help with language (XXX) Conduct a debate, with one student from each group acting as secretary. Rosa Macaya IES Pobla de Segur 55