Question

Please help me with biology

1. Online exercise: Find reports that document the relationship between the age of the mother and the risk for having a baby with Down Syndrome (Trisomy 21). For your interest only 2. Suppose that during transcription of a gene, RNA polymerase mistakenly inserts an incorrect base opposite the template DNA. This error results in an mRNA with an altered nucleotide sequence. Is this a mutation? For questions 3-10, consider the following mRNA, which is the product of a wild-type allele of a gene: 2 6 481 5'-UUAUGCCAUCCCAUGAGANAGCUACA CUAAAUAG-3' First, translate the mRNA using the genetic code table from your textbook (Figure 17-5, page 314) or from the Genetic Code lecture. Then, for the following changes in the mRNA sequence, determine the resulting change in the polypeptide. Use the following letters to describe the effect on the protein: A-silent mutation no effect on the protein made) B-missense mutation (alteration of a single amino acid) C-nonsense mutation (generation of a stop codon) D-frame shift, leading to a significant change in the polypeptide oss of an amino acid but the rest of the protein is normal F-a change in two amino acids but the rest of the protein is normal Assume that each question starts with the wild-type (norma sequence as shown at the top of this page. Question (3) has been answered for you. Predict the effect of: 3. Replacing the base at position (1) with a C. This mutation changes a GAG codon to a GAC codon, changing a glu to asp in the protein. This is a missense mutation, so the correct answer is B.

Answer 1

As tha age of women increases, their risk of developing down's syndrome also increases because there are more chances of improper chromosomal division in older eggs.

Reports links: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1166564/