HOLIDAY ASSIGNMENT GRADE: 10 TOPIC: HEREDITY AND EVOLUTION VERY SHORT ANSWER TYPE QUESTIONS (1 MARK EACH):1. A Mendelian experiment consisted of breeding pea plants bearing violet flowers with pea plants bearing white flowers. What will be the result in F1 progeny? 2. Give the respective scientific terms used for studying: i) the mechanism by which variations are created and inherited ii) the development of new type of organisms from the existing ones. 3. If a round, green seeded pea plant (RRyy) is crossed with wrinkled, yellow seeded pea plant (rrYY) and F1 generation plants are obtained. What will be the colour of the seeds obtained in F1 generation? Give reason for your answer. 4. No two individuals are absolutely alike in a population. Why? 5. Why are the traits acquired during the life time of an individual not inherited? 6. All the variations in a species do not have equal chances of survival. Why? SHORT ANSWER TYPE QUESTIONS (3MARKS EACH):1. How do Mendel’s experiments show that traits may be dominant or recessive? Explain with the help of a punnett square. 2. How is the equal genetic contribution of male and female parents ensured in the progeny? 3. A pea plant with blue colour flower denoted by BB is cross bred with a pea plant bearing white flower denoted by bb. a) What is the expected colour of flowers in their F1 progeny? b) What will be the percentage of plants bearing white flower in F2 generation, when the flowers of F1 plants were self pollinated? Show with the help of a cross. c) State the expected ratio of the genotype BB and Bw in the F2 progeny with the help of a cross. 4. List two differences in tabular form between dominant traits and recessive traits. What percentage/proportion of the plants in the F2 generation progeny were round, in Mendel’s cross between round and wrinkled green plants? 5. Differentiate between acquired and inherited traits by giving two examples for each. 6. Explain with the help of suitable examples why certain traits cannot be passed on to the next generation. What are such traits called? LONG ANSWER TYPE QUESTIONS (5 MARKS EACH):1. How did Mendel’s experiments show that traits are inherited independently? Depict it with the help of a cross. 2 .a. Why did Mendel select pea plants for conducting his experiments on inheritance? b. The sex of the child is determined by what they inherit from their father and not their mother”. Justify this statement with the help of a cross. 3. A cross was made between pure breeding pea plants one with round and green seeds and the other with wrinkled and yellow seeds. i) Write the phenotype of seeds obtained in F1 progeny. Give reason for your answer. ii) Write the different types of F2 progeny obtained along with their ratio when F1 progeny was self crossed. iii) State Mendel’s second law of inheritance. 4. a. What are dominant and recessive traits? b. “Is it possible that a trait is inherited but may not be expressed in the next generation”? Give a suitable example to justify this statement. 5. In a pea plant, the trait of flowers bearing Purple colour (PP) is dominant over white colour (pp). Explain the inheritance pattern of F1 and F2 generations with the help of a cross following the rules of inheritance of traits. State the visible characters of F1 and F2 progenies. 6. What is variation? How is variation created in a population? How does the creation of variation in a species promote survival?
