BioChem C785 - WGU - Module 1 - All Questions And Answers( With Best Solution)

BioChem C785 - WGU - Module 1 - all questions DNA replication is semiconservative, which allows each of the 2 strands to serve as a template for the new strands Correct Answer: true Recall that the DNA polymerase must bind a double-stranded polymer before it can start making its own DNA polymer. What helps the DNA polymerase to overcome this problem in DNA replication? Correct Answer: RNA primers Several components of cigarette smoke, including benzopyrene, insert themselves into the DNA and lead to several types of mutations such as frameshift mutations, including both insertions and deletion. Which repair pathway would be used to repair this type of damage? Correct Answer: Nucleotide Excision Repair Maternal smoking during pregnancy is hazardous yet common in many places. Many studies have associated prenatal smoking to unhealthy physical and psychological outcomes for the baby. Researchers know that maternal smoking affects are epigenetic in nature. Which event can be considered epigenetic in nature? Correct Answer: Changes in chromatin structure Blood is what type of inheritance? Correct Answer: codominance What is the probability that a child will have an autosomal dominant disease if their father is heterozygous for the allele and their mother is homozygous for the normal allelle? Correct Answer: 50% What is the complementary DNA strand for the DNA sequence 5'-ATT CGG GCT CCC - 3' Correct Answer: 5'- GGG AGC CCG AAT - 3' A research scientist is trying to create a new strain of bacteria that can produce a protein needed for her research. What molecule will act as a template in creating the new protein? Correct Answer: messenger RNA (mRNA) What is 1 direct effect of inhibiting translation? Correct Answer: the production of proteins would stop How many amino acids, and which ones, would be encoded by the following mRNA sequence: 5'- AUGACUCCCGGG -3' Correct Answer: 4: MET, THR, PRO, GLY Promoters are DNA sequences near the start of a gene that are recognized by transcription factors which recruit RNA polymerase to that gene for expression. This is an important aspect of transcriptions but not part of the mRNA processing. Correct Answer: true You are designing a piece of DNA for a project and must select the appropriate nitrogenous bases. Which combination of nitrogenous bases would you find most suitable for your work? Correct Answer: Adenine, Guanine, Thymine, Cytosine The DNA sequence is 3'-ATGATCCTT-5' is part of the template strand during DNA replication. What is the correct sequence for the newly made DNA? Correct Answer: 5'-TACTAGGAA-3' RNA nucleotides include the bases A, U, C, and G. RNA is single stranded and contains a ribose sugar in the sugar-phosphate backbone. There are several types of RNA in the cell, including mRNA, rRNA, and tRNA Correct Answer: true What would be the resulting mRNA sequence? Kevin's opsin gene at nucleotide positions 936 to 941: 5'-GCCTAG-3' (coding strand) and 3'-CGGATC-5' (template strand) Correct Answer: The sequence is the same as the coding: 5'-CGGUAG-3' The gene for blue opsin protein is located on chromosome 7, a non-sex chromosome. What kind of inheritance pattern would you expect to see with color blindness due to mutate blue opsin? Correct Answer: an equal distribution of color blindness between males and females In Kevin's case, a specific kind of mutation in the opsin gene resulted in the premature termination of the translation process. This resulted in shorter opsin protein than usual. What specific mutation could have caused this? Correct Answer: Nonsense mutation The nonsense mutation that causes Kevin's color blindness could have resulted from a malfunction of Correct Answer: DNA polymerase One strand of chromosome 2 has a DNA sequence that consists of: 5'- AAG CGG TAC GTA -3'. What will be the sequence of the complementary DNA strand? Correct Answer: 5' - TAC GTA CCG CTT -3' A woman is homozygous for an abnormal gene on Chromosome 2 that codes for an autosomal dominant disease. This means that she Correct Answer: will have the disease A man and woman with both type O blood have 4 children, what will be the blood types of their children? Correct Answer: 100% type O A couple has 6 children, 4 girls and 2 boys, all of whom have prominent chin dimples. If only the mother has a prominent chin dimple, what is the likely inheritance pattern for the chin dimple? Correct Answer: autosomal dominance Epigenetics: access to the promoter region of a gene by transcription factors is affected, environmental stimuli control gene expression, and gene expression is influenced by chemical modifications of the DNA and/or histone proteins Correct Answer: True Red green colorblindess Correct Answer: is due to a mutation in the opsin gene The LCT gene codes for Lactase, which is responsible for the breakdown of lactose. How is the Lactase activity increased? Correct Answer: the presence of lactose causes nucleosomes to separate, exposing the LCT gene Histone proteins can be chemically modified by addition of methyl group. As a result, nucleosomes pack tightly and the process of transcription is decreased at those DNA sites Correct Answer: True When the wrong nucleotide is added to a newly forming DNA strand during DNA replication: Correct Answer: distortion of the double helix retains its shape due to the pairing of A with T and G with C Mutation to the DNA strand that consists of a nucleotide sequence: 5'- CTG ACG TAT CTT AAT -3' Correct Answer: 5'- CTG ACG TAA CTT AAT-3' A patient with xeroderma pigmentosum is prone to developing multiple skin cancers starting in childhood. This occurs because of a mutation in a gene that codes for enzymes that help repair DNA damage through the nucleotide excision repair (NER) pathways. How does the NER differ from other repair mechanisms? Correct Answer: The error in one strand of DNA is removed as well as several nucleotides on either side of the error. The gap that was removed is filled in by DNA polymerase. Steps in the (BER) base excision repair: Correct Answer: 1. Removal of the damage by excising part of one strand to leave a gap 2. Ligation to restore continuity of the DNA backbone 3. Recognition of the damage Used in (PCR) Polymerase Chain Reaction: Correct Answer: 1. DNA template 2. DNA Nucleotides 3. Primer DNA polymerase is involved in DNA replication. DNA polymerase Correct Answer: adds nucleotides to the new NDA strand in the 5'-3' direction TRH is a very small molecule - 3 amino acids long - that helps regulate the amount of thyroid hormone produced by the thyroid gland. Although it is a small polypeptide, the mRNA that is created during transcription of the TRH gene is actually many, many nucleotides longer than the 9 nucleotides that would be required for a 3 amino acid polypeptide. What might reasonably explain why the actual mRNA produced during transcription is so much longer than the minimum 9 nucleotides required to code for the 3 amino acids? Correct Answer: Introns are removed from the mRNA after transcription of the gene that occurs What would be the resulting mRNA sequence from this template strand: 5'-ACA GCT GTC-3' Correct Answer: 5'-GAC AGC UGU-3' Hemophilia is an x-linked recessive condition Correct Answer: a person with at least one normal X chromosome without the hemophilia gene will not show signs of hemophilia An inherited autosomal recessive disease Correct Answer: can only occur if both parents carry at least one abnormal gene