Topic: Introduction to Mendelian Genetics and Inheritance Date: Oct 19 (Day 1) Overall exp. D2, D3 Specific D2.1, D3.3

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1 Topic: Introduction to Mendelian Genetics and Inheritance Date: Oct 19 (Day 1) Overall exp. D2, D3 Specific D2.1, D3.3 exp. Time 5 mins (10:00) 5 mins (10:05) Parts of Activity 1. Name Tags Students will create name tags and decorate them during transition between classes and selfintroduction for ease of identification and face-to-name recognition. 2. Introduce Self and Unit My name, about my name tag (interests) and my educational background. Invite students to approach you with any questions about university and research (at any time)! Unit Two: Genetics - Starting with unit diagnostic (see Annex A) to have students rate comfort level with various unit topics, terms and concepts, any things they want to learn in this unit, and any questions or concerns they have with the unit. - Terms include new and familiar ones: DNA, genotype, phenotype, traits, mitosis, parts of an animal or plant cell, cloning, stem cell research, pedigree (charts), inheritance, Punnett squares, reproduction (sexual and asexual), and crossing and breeding. o Rating scale based on understanding: very good familiar not at all o Students record pre-unit understanding using one colour or shape, to allow comparison to post-unit understanding using a different colour or shape indicator. - Prompts for expectations for unit: any of above concepts or others that you re interested in learning more about? That you ve heard referenced on social media, news, etc. 15 mins (10:20) (5 min per Q) 3. Think-Pair-Share Explain the process of Think-Pair-Share and establish ground rules for sharing: - Read question presented - When ready, turn to your elbow or back partner and discuss - Share your interesting or favourite responses with the rest of the class o Share as little or as much as you like! To have students connect the unit with other subjects, life experiences, and prior knowledge, have them answer the following questions (record shared answers for each, ask them WHY?): - HOW do you think genetic information is passed from one generation to the next? o Key terms: genes, DNA, chromosomes, heredity, inheritance, dominance, recessive, alleles, meiosis, etc. o Prompts: If the mom has blue eyes and dad has brown eyes, what colour eyes might their children have? Why?

2 Will there be a blend in traits? Is one set of genes stronger than the other? o If a black cat and a tabby (orange) cat mate, what will their offspring look like? - Why are some characteristics or traits passed on from parent to child and not others? o Key terms: lack genetic basis, not heritable traits, non-coding o What about traits that skip generations? (Grandparent to grandchild blue eyes, red hair, musical talent, earlobe shape, etc.) - Why is there so much variation in the human population with respect to their appearance (how the look)? o Possible answers: diet, geographical regions, reproduction (mixing between different groups or individuals with different traits), males and females (gender effects), external and internal factors (plasticity, genes, etc.) o Prompt: Twins are genetically identical, yet they can still differ widely why? 15 mins (10:35) Key point of discussion: existence of heritability - Recall evolution and natural selection, what were some key terms used when referring to the passing of genetic information of traits from one generation to the next? o For natural selection to occur, the affected trait must be heritable 4. Class Trait Survey Students will examine their inherited traits by doing a class survey. Afterwards, they can return home and compare their traits with those of their family members (siblings, parents, etc.). In partners, they will examine these characteristics: - Hair colour (non-artificial, i.e. not dyed): black, brown, blonde, red, etc. - Eye colour (non-artificial, i.e. not coloured contacts): brown, hazel/green, blue - Hairline (on forehead, pull back bangs): straight, rounded, widow s peak - Dimples (smile): dimples, no dimples - Thumbs (clench fist): straight, curved (a.k.a. Hitchhiker s thumb) - Tongue rolling: non-roller, roller (U-shape), multiple roller (wave) - Handedness (writing, sports, turning head): right, left, ambidextrous (indifferent, both) - Earlobe (try pulling at bottom end): free, attached Key idea: characteristic is what varies (hair colour), traits are the different variations (black, brown, blonde, red, etc.). Students will record data in a table (in their notebooks) similar to this with their partners: Characteristic Student A Student B Hair colour Blonde Brown Teacher records a class chart like this: Characteristic Trait 1 Trait 2 Trait 3 or 4 Hair colour Black Brown Blonde Eye colour Brown eyes Hazel/Green eyes Blue eyes

3 35 min (11:05) After completing the survey, ask if students see any patterns or what the data means. Ask students if they think the class data is representative of the human population why or why not? - Students should recognize that you need demographic data to find a sample group and size that is representative of the human population. Even then, it is difficult to determine accurate representation. Therefore, a larger sample will yield more representative results. 5. History of Establishment of Genetic Theories Early farmers and breeders - Recognized patterns in traits or characteristics being passed down through generations of animals (dogs, cats, livestock cattle, chicken, etc.). o Through observations and trial-and-error, they discovered that mating individuals that had the best or most favoured traits with each other or others, that their offspring would yield better traits (than average) or become more similar. - Unlike natural selection and evolution that Darwin studied, farmers and breeders utilized artificial selection (by blocking out unwanted traits themselves) to cause changes in the population, either immediately or over time. - They established purebred or prized lines of animals to maintain their traits o Lacked a scientific understanding of inheritance: based purely trail-and-error. In the 19 th century (1860s), the predominant theory of inheritance was the blending theory. It was believed that parental traits would be passed onto their offspring and blended, supported by observations with dogs, flowers, etc. Darwin proposed pangenesis as the mechanism for heredity. - Every tissue, cell and living part of an organism produced minute, unseen gemmules (granules, germs) that carried inheritable characteristics and were transmitted to the offspring via the reproductive process. Each part produced information only about itself gemmules for hands and feet, not for whole organisms) o Some germs remain dormant for generations, others routinely carried on o Every child built from a mixture of parents and grandparent gemmules - Despite supporting examples, this theory did not always hold true. - Prompt: has anyone ever told you that you look like your family (mom, dad, siblings)? That you have your mom/dad s eyes, nose, hair, laugh, smile, etc.? o Inheritance was recognized, but some traits were passed straight from parent to child, traits skipped generations, and some children or siblings simple resembled each other, rather than being identical or a mix of traits. Mendel and Pea Plants - Gregor Mendel, a friar that lived in the 19 th century, enjoyed experimenting with plants in his garden. He made many different experiments and observations to test

4 blending and other theories of inheritance. He is referred to as the father of genetics for his work with garden pea plants. - Why use the pea plants as a model organism? o Fast reproduction (short generation time recall: evolution) o Many observable inheritable traits o Can control breeding how? Pea Plant Reproduction - Prompt: What are the different ways that plants can reproduce? (Sexual, asexual, pollination, seeds in fruits, seeds via wind or weather, etc.) - Pea plants reproduce sexually in two ways: o Self-fertilization (same plant, identical genetic material) o Cross-fertilization (different plants, varied genetic material) - Controlled breeding by manipulating the pea plants: o Remove anthers from all plants (prevents self-fertilization) o Manually transfer pollen from plant of choice to another plant (brush) Pea Plant Characteristics - Mendel chose garden pea plants because they have many observable characteristics that are heritable, easily distinguishable and dichotomous.

5 Breeding and Terminology - Garden peas are true-breeding plants. When they reproduce with another truebreeding plant with a similar trait (via self-fertilization or cross-fertilization), they will always produce offspring with the same trait (for that specific characteristic). o Draw example with true-breeding purple flower self- or cross-fertilizing. - If you cross (successfully mate or breed) true-breeds of different traits for the same characteristic, you will get a hybrid. o Recall: characteristics are what varies, and traits are the variations. 6. Exit Card (Checking student understanding) Students will write the following on a Post-It and attach it to their diagnostic to hand-in: - Their name (First and Last) - One thing you found interesting from today s lesson (from diagnostic or PPT) - One thing you d like explained in further detail, or on which more time should be spent (e.g. any new terms or concepts, go slower next time) Summary of Terms and Topics (Covered in this lesson) - Diagnostic: DNA, genotype, phenotype, traits, mitosis, parts of an animal or plant cell, cloning, stem cell research, pedigree (charts), inheritance, Punnett squares, reproduction (sexual and asexual), and crossing and breeding - Heredity, inheritance, generation, and genetics - Traits, characteristics, resemblance, population representation, and sample size - Breeding, natural vs. artificial selection, evolution, purebred, blending theory and pangenesis - Mendel, pea plant, model organism, sexual and asexual reproduction, and pea plant reproduction - Pea plant characteristics: distinguishable and dichotomous, true-breeding plants, and hybrids

6 Annex A: Genetics Unit Diagnostic Unit Diagnostic: What do you know? Before (colour/shape) After (colour/shape) Concept, term or topic Level of comfort or understanding DNA very good familiar not at all Genotype and phenotype very good familiar not at all Traits very good familiar not at all Mitosis very good familiar not at all Parts of a cell (animal or plant) very good familiar not at all Cloning very good familiar not at all Stem cell research very good familiar not at all Pedigree (charts) very good familiar not at all Inheritance very good familiar not at all Punnett squares very good familiar not at all Reproduction (sexual and asexual) very good familiar not at all Crossing and breeding very good familiar not at all What do I expect to or want to learn in this unit? What questions or concerns do I have about this unit?