This biology question covers important biological concepts and processes. The step-by-step explanation below helps you understand the underlying mechanisms and reasoning.
ScanSolve AI Answer
You're on a roll — here are the solutions to your questions: 6.1 a) Step 1: Count the number of squares in the pedigree chart. Squares represent males. Jon (Generation 1) Paul (Generation 2) Lyall (Generation 3) There are 3 males. 3 b) Step 1: Count the number of horizontal levels in the pedigree chart. Each level represents a generation. Generation 1: Jon and Linda Generation 2: Gabby, Paul, and Fiona Generation 3: Mieke and Lyall There are 3 generations. 3 6.2 a) Step 1: Identify Jon's genotype from the diagram, which is Hh. Step 2: The letter H represents the allele for hearing, and h represents the allele for deafness. Since Jon has at least one dominant H allele, he can hear. The phenotype of Jon is: Hearing b) Step 1: Paul is a male (square) and is not shaded, indicating he can hear. Step 2: Paul's parents are Jon (Hh) and Linda (hh). Step 3: Linda (hh) can only pass on an 'h' allele. Step 4: Since Paul can hear, he must have inherited the dominant 'H' allele from Jon. Therefore, Paul's genotype is: Hh 6.3 Lyall is deaf, meaning his genotype is hh. For Lyall to have this genotype, he must have inherited one 'h' allele from each of his parents. His parents are Paul and Gabby. Paul's genotype is Hh (as determined in 6.2b), so he carries the recessive allele and can pass it on. Gabby is shown as hearing (unshaded circle), but since she had a deaf child (hh), she must also carry the recessive 'h' allele. Therefore, Gabby's genotype is also Hh. Both parents are heterozygous carriers for deafness, and they each passed on their recessive 'h' allele to Lyall, resulting in his deafness. 6.4 Step 1: Determine the genotypes of Lyall and the woman. Lyall is deaf, so his genotype is hh. The woman is homozygous dominant for hearing, so her genotype is HH. Step 2: Perform a genetic cross using a Punnett square. Parents: hh (Lyall) × HH (Woman) Gametes from Lyall: h, h Gametes from Woman: H, H |c|c|c| & H & H \\ h & Hh & Hh \\ h & Hh & Hh \\ Step 3: Determine the genotypes and phenotypes of the offspring. All possible offspring genotypes are Hh. All offspring will have the phenotype of hearing. Step 4: Calculate the percentage chance of them having a deaf child. Since all offspring are Hh (hearing), there is no chance of having a deaf child. 0% Got more? Send 'em!