Pattern of inheritance Mendelian Genetics

Pattern of inheritance Mendelian Genetics

1. PATTERN OF INHERITANCE: Phenotypic Expressions of Traits

2. OBJECTIVES Hello! I'm Teacher Terry, and I'll be guiding you through today's lesson. Let's dive into learning more about simple patterns of inheritance and how you can predict phenotypic expressions in different organisms, including yourself! Come and join me on this exciting journey! After going through this lesson, you are expected to: explain which traits will appear by using simple patterns of inheritance; construct a Punnett square to predict the traits of an offspring from a given set of parent traits; p redict phenotypic expressions of traits following simple patterns of inheritance (S8LT-IVf-18); and recognize how traits are passed from parents to offspring and show interest in learning about their own inherited traits. PROCEED

3. INTRODUCTION Welcome to today’s lesson on predicting how traits are expressed based on simple inheritance patterns! Have you ever wondered why you have certain traits, like your eye color or the shape of your earlobes? These traits are influenced by genetics, which is the study of how traits are passed from parents to offspring. In this lesson, we will explore how traits are inherited and how to predict their expressions using patterns of inheritance, such as dominant genes and recessive genes . We’ll use activities like Punnett squares and real-life examples to help you understand how to predict the probability of traits appearing in offspring. By the end of this lesson, you’ll know how traits are inherited and how to predict their expressions. Let’s get started! N E X T

4. GUIDE CARD Kindly take note of the following reminders that you need to follow in using the e-SIM.   Read and follow the instruction carefully. Honesty is the best policy! Be honest in taking the test so that you know how much you have learned about the lesson. Do all the activities and do not skip any part of the lesson as these will help you understand the topic better. Stay focused and take your time. This will help you grasp the lesson more effectively. If you have any questions, feel free to reach out for help! Learning is a journey best traveled with support. Enjoy the learning experience! Good Luck! N E X T

5. ACTIVITY CARD Before diving into the topic, it’s important to assess what you already know. Make sure to read the questions comprehensively for you to answer them correctly. Direction: Let’s assess what you already know about pattern of inheritance. Read the questions carefully and observe honesty in doing the task. Select your answer from the choices provided. N E X T

6. ACTIVITY 1 1. In genetics, what does the term "phenotype" refer to? N E X T A. The genetic makeup of an organism. B. The physical appearance or traits of an organism. C. The environment where the organism lives. D. The number of chromosomes in an organism.

7. ACTIVITY 1 2. If a gene for brown eyes (B) is dominant and a gene for blue eyes (b) is recessive, what eye color will an offspring with the genotype Bb most likely have? N E X T A. Blue eyes B. Brown eyes C. Green eyes D. No eye color

8. ACTIVITY 1 3. In a Punnett square, what do the letters outside the boxes represent? N E X T A. The traits of the parents B. The traits of the offspring C. The dominant traits only D. The recessive traits only

9. ACTIVITY 1 4. If two parents both have the genotype bb for blue eyes, what is the most likely eye color for their child? N E X T A. Brown eyes B. Blue eyes C. Green eyes D. Hazel eyes

10. ACTIVITY 1 5. Which of the following describes a recessive trait? N E X T A. It always shows up, even if only one parent passes it down. B. It only shows up when both parents pass it down. C. It is stronger than a dominant trait. D. It is never passed to offspring.

11. ACTIVITY 2 RED FLAG OR GREEN FLAG ACTIVITY INSTRUCTION You will be given a statement related to patterns of inheritance. Read each statement carefully Decide if the statement is T RUE or FALSE by clicking the Green flag for TRUE and Red Flag for FALSE. Each flag have corresponding points. Correct answers will earn you plus points and incorrect answer will giv e you minus points. So, choose wisely! Remember, that HONESTY is still the best policy! N E X T

12. RED FLAG OR GREEN FLAG P R O C E E D

13. ACT. 2 RED FLAG OR GREEN FLAG A dominant trait will always show if there is one dominant allele. N E X T

14. ACT. 2 RED FLAG OR GREEN FLAG A Punnett square is used to predict how traits will be passed from parents to offspring. N E X T

15. ACT. 2 RED FLAG OR GREEN FLAG A recessive trait will only show if both genes are recessive. N E X T

16. ACT. 2 RED FLAG OR GREEN FLAG A Punnett square is used to predict how traits will be passed from parents to offspring. N E X T

17. ACT. 2 RED FLAG OR GREEN FLAG If two parents have different traits, their child will only show the dominant trait. N E X T

18. ACTIVITY 3 PROBLEM-SOLVING: PUNNET SQUARE Direction: Use a Punnett square to cross two pink snapdragon plants (RW) and find the possible phenotypes of their offspring. Calculate the probabilities of each flower color (red, pink, white). In snapdragons, flower color exhibits incomplete dominance. When a plant with red flowers (R) is crossed with a plant with white flowers (W), the resulting flowers are pink (RW). GUIDE QUESTIONS: What are the possible genotypes and phenotypes of the offspring if two pink snapdragon plants (RW) are crossed? What is the probability of each flower color (red, pink, white) in the offspring? N E X T

19. ACTIVITY 3 PROBLEM-SOLVING: PUNNET SQUARE N E X T Q1. Q2.

20. IN DETAILS N E X T Gregor Johann Mendel (1822-1884) (Father of Genetics) He was an Austrian monk in 19 th century who conducted extensive experiments with pea plants to study inheritance. Mendel performed thousands of crosses in his monastery garden. He discovered how traits are passed down through generations, identifying dominant and recessive traits. His groundbreaking work established the foundation of modern genetics. N E X T Gregor Mendel Gregor Mendel’s Experiment Mendelian Heredity Punnett Square Provides a discussion of the lesson. Read and comprehend the lecture part and you can take down important concepts for your reference.

21. IN DETAILS Gregor Mendel Gregor Mendel’s Experiment Mendelian Heredity Punnett Square The Pea Experiment by Gregor Mendel Mendel grew pure-breeding plants by self-pollinating many generations until all offspring had the same traits as their parents. He used several traits such as smooth or wrinkled ripe seeds, yellow or green seed albumen, purple or white flower, tall or dwarf stem length, and etc. N E X T

22. IN DETAILS Gregor Mendel Gregor Mendel’s Experiment Mendelian Heredity Punnett Square Steps How Mendel Conducted The Experiment . Mendel establish two pea plant populations with two different traits (e.g. height), breeding them until they constantly producing offspring identical to the parents. After this, he then bred them with each other to observe how the offspring inherited the traits. STEP 1 N E X T Mendel allowed the generation showing only the dominant trait to self-fertilize, producing a new generation where the recessive trait reappears. STEP 1

23. IN DETAILS Gregor Mendel Gregor Mendel’s Experiment Mendelian Heredity Punnett Square Steps How Mendel Conducted The Experiment N E X T Mendel's results from his pea plant experiments: Initial Cross: A tall plant is crossed with a short plant, resulting in all tall offspring in the F1 generation. Self-Fertilization: The tall F1 plants self-fertilize, leading to the F2 generation. F2 Results: In this generation, the ratio is 3 tall plants to 1 short plant, showing that the short trait reappears. This highlights Mendel's principles of dominance and segregation.

24. IN DETAILS Gregor Mendel hypothesized that traits are controlled by hereditary "factors," now known as genes , and that each trait is regulated by a pair of these factors, called alleles . His findings led to the formulation of the three principles of heredity, explaining how traits are inherited. Law of Dominance (First Law of Inheritance) It states that traits are controlled by pairs of factors (genes), and in heterozygous pairs, one factor dominates the other. In a monohybrid cross of contrasting traits, only the dominant trait is expressed in the F1 generation, while both traits appear in the F2 generation in a 3:1 ratio. The dominant trait is the one that shows up, while the recessive trait is masked. Example: the cross between tall (TT) and dwarf ( tt ) pea plants, as all F1 offspring were tall. N E X T Gregor Mendel Gregor Mendel’s Experiment Mendelian Heredity Punnett Square

25. IN DETAILS 2. Law of Segregation (Second Law of Inheritance) It states that during meiosis, alleles (gene pairs) separate so that each gamete contains only one allele for each trait. In a monohybrid cross, both alleles reappear in the F2 generation without blending. The law is based on four key concepts: genes have multiple forms (alleles), alleles separate during meiosis, organisms inherit two alleles for each trait, and one allele is dominant while the other is recessive. N E X T Gregor Mendel Gregor Mendel’s Experiment Mendelian Heredity Punnett Square

26. IN DETAILS 3. Law of Independent Assortment It states that allele pairs separate independently during the formation of gametes. The resulting traits are transmitted to offspring independently of one another. Four Key Ideas 1. Genes have different versions, called alleles. 2. Organisms receive two alleles, one from each parent, during sexual reproduction. 3. During meiosis, these alleles separate, ensuring each gamete carries only one allele for a trait. 4. In heterozygous pairs, one allele is dominant while the other is recessive. N E X T Gregor Mendel Gregor Mendel’s Experiment Mendelian Heredity Punnett Square

27. IN DETAILS PUNNETT SQUARE Devised by Reginald C. Punnett in 1905. A Punnett square is a simple diagram used to predict how traits are passed from parents to offspring. It shows how the genes from each parent combine and helps figure out the chances of different traits appearing in the offspring. N E X T Gregor Mendel Gregor Mendel’s Experiment Mendelian Heredity Punnett Square When two heterozygous pea plants for flower color are crossed, the offspring will have a 3:1 ratio, meaning about 75% (3:1) of the offspring will have the dominant purple color.

28. TRY ME! N E X T In guinea pigs, black fur (B) is dominant over white fur (b). A homozygous black guinea pig (BB) is crossed with a heterozygous black guinea pig (Bb). What is the possible phenotypes of their offspring? Complete the Punnett squares according to the problem given below.

29. ASSESSMENT CARD You’re almost done! In this activity, you will evaluate your understanding of the topic in this module. Here, we will analyze what you’ve learned and identify areas of strength and areas for improvement. Direction: Read the questions carefully and observe honesty in doing the task. Select your answer from the choices provided and you will find out if your answer is correct! N E X T

30. 1. Who is known as the "Father of Genetics"? N E X T A. Charles Darwin B. Gregor Mendel C. James Watson D. Louis Pasteur ASSESSMENT CARD

31. 2. Which of the following describes a heterozygous genotype? N E X T A.TT B. Tt C. tt D. TTT ASSESSMENT CARD

32. 3. In a Punnett square, what do the letters inside the boxes represent? N E X T A. Possible genotypes of the offspring B. The phenotype of the parents C. The gametes produced by the parents D. The sex of the offspring ASSESSMENT CARD

33. 4. Which of Mendel's principles states that genes for different traits are inherited independently of one another? N E X T A. Principle of Segregation B. Principle of Incomplete Dominance C. Principle of Independent Assortment D. Principle of Codominance ASSESSMENT CARD

34. 5. What principle states that allele pairs separate during gamete formation, and each gamete carries only one allele for each gene? N E X T A. Principle of Dominance B. Principle of Independent Assortment C. Principle of Segregation D. Principle of Genetic Inheritance ASSESSMENT CARD

35. ENRICHMENT CARD PROBLEM SOLVING: DIHYBRID CROSS Direction: Use a Punnett square to cross two pea plants and find the possible phenotypes of their offspring. Calculate the probabilities of each traits (round/wrinkled). In pea plants, round seeds (R) are dominant over wrinkled seeds (r), and yellow seeds (Y) are dominant over green seeds (y). A plant that is heterozygous for both traits ( RrYy ) is crossed with another plant that is also heterozygous for both traits ( RrYy ). Guide Questions: What are the possible genotypes and phenotypes of the offspring? What is the probability of getting offspring with round yellow seeds? N E X T

36. ACTIVITY 3 PROBLEM-SOLVING: DIHYBRID CROSS N E X T Q1. Q2.

37. CONGRATULATIONS!!! You can now proceed to the next lesson.

38. Criteria 4 - Excellent 3 - Proficient 2 - Developing 1 - Beginning Understanding of Concepts Clear understanding of genetics concepts. Solid understanding with minor errors. Partial understanding with significant errors. Limited understanding of concepts. Punnett Square Setup Correctly sets up the Punnett square. Mostly correct setup with minor mistakes. Some errors in the setup. Incorrect or incomplete setup. Genotype/Phenotype Calculation Correctly calculates all genotypes and phenotypes. Mostly correct calculations with minor errors. Some errors in calculations. Major errors in calculations. Grammar Uses correct scientific terms consistently. Mostly uses correct terms with few mistakes. Uses some correct terms, but often incorrectly. Rarely uses correct terms. Explanation Clear and detailed explanation of steps. Adequate explanation with some details missing. Partial explanation lacking clarity. Little or no explanation provided. Accuracy Completely correct final answer. Mostly correct final answer with minor errors. Some errors in the final answer. Incorrect final answer. RUBRICS

39. Science – Grade 8 Alternative Delivery Mode Quarter 4 – Module 4: Mendelian Genetics First Edition, 2020 https://www.genome.gov/genetics-glossary/johann-gregor-mendel https://www.britannica.com/biography/Gregor-Mendel https://opentextbc.ca/biology/chapter/8-2-laws-of-inheritance/ https://k12.starbooks.ph/pluginfile.php/5936/mod_resource/content/26/index.html https://www.thoughtco.com/independent-assortment-373514 REFERENCE CARD N E X T

40. JOB WELL DONE!!! N E X T

41. JOB WELL DONE!!! N E X T

42. ACT. 2 RED FLAG OR GREEN FLAG -1 points

43. ACT. 2 RED FLAG OR GREEN FLAG +1 points

44. ACT. 2 RED FLAG OR GREEN FLAG -2 points

45. ACT. 2 RED FLAG OR GREEN FLAG -2 points

46. ACT. 2 RED FLAG OR GREEN FLAG +2 points

47. ACT. 2 RED FLAG OR GREEN FLAG -2 points