Grade 9 Science: Patterns of Inheritance
Explore fundamental concepts of heredity, Mendelian genetics, and Punnett squares in this Grade 9 Science worksheet.
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Grade 9 Science: Patterns of Inheritance
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Read each question carefully and answer to the best of your ability. Show your work for Punnett square problems.
1. Which of the following describes an organism with two identical alleles for a particular trait?
Heterozygous
Homozygous
Phenotype
Genotype
2. In a monohybrid cross between two heterozygous parents (Aa x Aa), what is the expected phenotypic ratio of the offspring?
1:2:1
3:1
9:3:3:1
1:1
3. The passing of traits from parents to offspring is called .
4. A square is a diagram used to predict the genotypes of a particular cross or breeding experiment.
5. An allele that is only expressed when two copies are present is described as .
6. Define the terms 'genotype' and 'phenotype' and provide an example for each.
7. In pea plants, tall (T) is dominant over short (t). Cross a heterozygous tall plant with a short plant. Fill in the Punnett Square below and state the genotypic and phenotypic ratios of the offspring.
Genotypic Ratio:
Phenotypic Ratio:
8. Gregor Mendel is known as the 'Father of Genetics'.
True
False
9. A recessive allele will always be expressed in the phenotype.
True
False