Tutorial 4 Assignment Template

Fall 2023 Tutorial 4 – Inheritance & Information Transfer BIOL 1103 Tutorial 4 Assignment Full Name: ____________________ Student #: ________________ Lab section: __________ Although the tutorial work may be completed in groups, all work submitted must be completed individually. It is important that you do not copy from the lab manual or from each other. DO NOT plagiarize! Unless otherwise specified in the question, all answers should be written using complete sentences, paragraph style. Part I: Mendelian Inheritance Colour blindness is an X-linked recessive disorder characterized by the inability to either differentiate between colours or see colour at all. Cystic fibrosis is an autosomal recessive disorder characterized by the abnormal secretion of thick mucus rather than thin. The resulting thick mucus can cause adverse effects in the lungs, pancreas, liver, kidneys, and intestines. Often men afflicted by this condition are rendered infertile. Solon ( ♂) is colour blind and is a carrier for cystic fibrosis and his partner, Gwynevere ( ♀) , is a carrier for both colour blindness and cystic fibrosis. Solon and Gwynevere have 4 offspring: Priscilla ( ♀) , Reah ( ♀) , Logan ( ♂) , and Andre ( ♂) . Priscilla is a carrier for colour blindness and has cystic fibrosis. Reah has colour blindness and is a carrier for cystic fibrosis. Logan does not carry the mutation for colour blindness but is a carrier of cystic fibrosis. Finally, Andre is both colour blind and is afflicted by cystic fibrosis. Using the information provided above, answer the following questions regarding the family’s genetics. IMPORTANT: Use the following notation to answer all questions: Individuals with colour blindness are delineated by X b , whereas X B is used for individuals without colour blindness. Individuals with cystic fibrosis are delineated by f , while those without cystic fibrosis are delineated by F . 1. What are the genotypes of Solon and Gwynevere (2 marks) ? 2. What are the genotypes of Priscilla, Read, Logan, and Andre (4 marks) ? 1

Fall 2023 Tutorial 4 – Inheritance & Information Transfer BIOL 1103 3. Construct a dihybrid cross showing the possible genotypes of Solon and Gwynevere’s offspring (4 marks) 4. Based on the dihybrid cross you constructed in the previous question, state the probabilities ( as a percentage ) of Solon and Gwynevere’s having offspring with the phenotypes below (6 marks) . a. An offspring without any genetic mutations ( i.e., homozygous dominant for both normal vision and cystic fibrosis). b. An offspring with cystic fibrosis. c. Priscilla being a carrier for colour blindness and cystic fibrosis. d. Reah having colour blindness and being a carrier for cystic fibrosis. e. Logan having normal vision and being a carrier for cystic fibrosis. f. Andre being afflicted by both colour blindness and cystic fibrosis. Part II: Information Transfer The omitted bases in the following instructions will be provided during your tutorial session. Below is a sequence of eukaryotic DNA containing a hypothetical gene for protein X. The base that is first (at the 5’ end) in the sequence is at position __ . Remember that DNA sequences do NOT have a position 0. The translational start site is the first initiating codon (start codon) encountered after the transcriptional start (+1). This gene has three exons. The last base of the first exon is the __ at position __ ; the first base of the second exon is the __ at position 2