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Please answer both the parts of these questions. I only had one question left for my subscription. if you cannot answer this please let someone else do it but please whoever is doing it do it correctly- both the parts. Thank you!
This is a graded discussion: 8 points possible due May 30 at 12pm 128 128 Module 2: Discussion #2-Genotypic and Phenotypic Ratios Please note-you won't be able to view your peer's responses until you've posted your own This week you started learning about Mendelian Genetics and Mendel's Law. Punnett squares were introduced which is a useful way for predicting the allele composition of offspring from a cross between individuals of known genetic makeup. The parental generation (P) is the first set of parents crossed. The F1 (first filial) generation consists of all the offspring from the parents. You learned about The Law of Segregation as well as The Law of Independent Assortment Part l: Genes come in different alleles. A dominant allele hides a recessive allele and determines the organism's appearance. A Punnett square is a useful tool for predicting genotypes (allele combinations) and phenotypes observable traits) of offspring from genetic crosses involving Mendelian traits. The Punnett square below depicts 2 parents who are heterozygous, 'Aa'. Part I of this discussion assignment will be graded based on accuracy. At least 350 words Aa X Aa AA Aa Aa 1.Define phenotype and genotype in your own words (basically, don't just copy/paste, paraphrase so you don't have to use quotations) 2. What would be the genotypic ratios be? What are the phenotypic ratios of: AA, Aa, Aa, aa? Be sure to give us the ratios in this format: 9:3:3:1 (this is just an example) 3. Explain why they are the same or different

Answer 1

Part I

A. Pheno (in biology) means observable character of an organism. Phenotype means the external of observable appearance of an organism. For example - height, colour, length.

• Geno means related to genes. Genotype is genetic makeup of an organism. This is due to presence of genes that control various trait.

B. Genotypic ratio = 1 (AA) : 2 (Aa) : 1 (aa)

• Because in offspring 1/4 are AA, 2/4 are Aa and 1/4 are aa

Phenotypic ratio = 3 (dominant) : 1 (recessive trait)

• Because dominant trait can be expressed both in homozygous dominant (AA) and heterozygous (Aa). Therefore 3/4 offspring will express dominant trait. Recessive trait is expressed only in homozygous and therefore 1/4 offspring will express recessive phenotype

C. They are different because dominant trait can be expressed both in homozygous and heterozygous condition, therefore offspring will express dominant trait both in AA and Aa. Recessive trait is expressed only in homozygous recessive condition (aa)

Part II (I've provided multiple answers, choose the one which you like)

A. Autosomal recessive disease like cystic fibrosis, sickle cell anemia, phenylketonuria.

• These disease are expressed only in homozygous recessive condition (aa) therefore there is 1/4 chance of offspring being affected.

B. Autosomal dominant disease like Marfan's disease, neurofibromatosis type I, achondroplasia

• These disease are expressed both in AA (homozygous dominant) and Aa (hetrozygous) genotype and therefore offspring has 3/4 chance of being affected by the disease

These disease can be detected by genetic testing in parents or fetus and parents can be guided about survival and associated morbidities in child.

Feel free to comment if you have any problem in understanding this answer.