PUBH 6011 FINAL LATEST EXAM REAL EXAM QUESTIONS AND ANSWERS/ PUBH6011 FINAL EXAM STUDY GUIDE | A GRADE

PUBH 6011 FINAL LATEST EXAM REAL EXAM QUESTIONS AND ANSWERS/ PUBH6011 FINAL EXAM STUDY GUIDE | A GRADE Two differences between virus and bacteria - CORRECT ANSWER- 1. Bacteria are a single cell and can exist on their own (no nuclei or substructures) 2. Viruses must invade a host cell and use its genetic DNA Role of DNA in protein synthesis ?- CORRECT ANSWER- DNA acts as a template for RNA and encodes the sequence of proteins Role of mRNA in protein synthesis - CORRECT ANSWER- mRNA is a singlestrand of RNA, it moves out of the nucleus into the cytoplasm. Ribosomes read the mRNA code to produce a chain of amino acids. Role of tRNA in protein synthesis - CORRECT ANSWER- tRNA brings amino acids made by the mRNA to the ribosome where proteins are constructed, reads the message of nucleic acids and TRANSLATES it into proteins. Role of ribosomes in protein synthesis - CORRECT ANSWER- Protein factories in the cytoplasm. Binds to mRNA and reads the code in it to produce a chain of amino acids. Catalyze the synthesis of protein chains from amino acids. How do biological and genetic factors influence our response to environmental hazards? - CORRECT ANSWER- Genes can determine the progression and severity of a disease, even if the disease wasn't caused by the environment. What is the microbiome? - CORRECT ANSWER- The microbiome are the microbial organisms that live within the intestines, skin, and within mucus membranes. How does the microbiome prevent disease? - CORRECT ANSWER- The microbiome can impact how toxicants are absorbed (or not absorbed) into the body and impact our susceptibility to disease. Define: Environmental response gene - CORRECT ANSWER- This dictates a person's response to certain environmental exposures, but without exposure it has no health consequence. Explain how environmental factors influence genetic expression. - CORRECT ANSWER- Epigenetics - heritable changes in the phenotype without changes in the DNA structure (genotype). The environment can change what genes are expressed and when. Epigenetics determines which genes are expressed (turned on or off). Central Dogma of DNA to Protein - CORRECT ANSWER- DNA - Transcription - RNA - Translation - Protein Types of Genetic Mutations (two big categories) - CORRECT ANSWER- 1. Microlesions 2. Macrolesions Types of Microlesions (genetic mutations) - Two Types - CORRECT ANSWER1. Base-pair substitution 2. Frameshift Mutations Types of Macrolesions (genetic mutations) - Two Types - CORRECT ANSWER1. Chromosome Aberrations 2. Changes in chromosome number (aneuploidy, polyploidy) Explain base-pair substitution - CORRECT ANSWER- Changes the sequence of the genetic base pairs (AT/GC) due to an interaction with an outside chemical structure. Point mutations. Does not always change the function (but can) Explain frameshift mutations - CORRECT ANSWER- Insertion or deletion of one or more bases (AT/GC) in the sequence. Changes the reading frame. Almost always get an altered protein, often leads to non-functional. Explain Chromosome Aberrations - CORRECT ANSWER- Change in chromosome structure via deletion, duplication, inversion, translocation. Benzene, ionizing radiation can cause it. Explain changes in chromosome number (two types) - CORRECT ANSWER- 1. Aneuploidy - increase in number of one or more chromosomes (usually sperm/eggs). Odd number of chromosomes in gamete (trisomy/monosomy) 2. Polyploidy - increase in a whole set of chromosomes Name the 4 types of chromosomal aberrations (macrolesion) - CORRECT ANSWER- 1. Deletion 2. Translocation 3. Duplication 4. Inversion Define chromosomal deletion - CORRECT ANSWER- A chromosome segment is lost completely Define chromosomal translocation - CORRECT ANSWER- A segment from a chromosome is transferred to another one Define chromosomal duplication - CORRECT ANSWER- A segment from one chromosome is transferred to its homologous chromosome, duplicating of some genes Define chromosomal inversion - CORRECT ANSWER- A segment of a chromosome arm is inverted Name the 3 types of point mutations (microlesion) - CORRECT ANSWER- 1. Silent 2. Nonsense (codes for STOP) 3. Missense (can change function or not)