MBH Exam 4 Questions and Answers latest 2022

endemic disease - ANSWER disease constantly present in a population sporadic disease - ANSWER disease that occurs occasionally in a population Age, nutrition, stress, and climate are all factors affecting ______. - ANSWER the distribution and composition of normal microbiota Factors that determine microbiota - ANSWER nutrient requirements, physical chemical mechanical factors, host defense mechanisms deletion mutation - ANSWER a mutation in which one or more pairs of nucleotides are removed from a gene insertion mutation - ANSWER a mutation in which one or more nucleotides are added to a gene frameshift mutation - ANSWER mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide When an enzyme comes to a stop codon, the entire proccess ______ since there is no _____. - ANSWER stops ; amino acid The 3 Stop Codons are ______________, _______________, and _____________. - ANSWER UAA, UAG, UGA Types of base substitutions include: - ANSWER silent, missense, nonsense nonsense mutation - ANSWER subsitution of wrong nucleotide into DNA that produces an early stop codon missense mutation - ANSWER A point mutation in which a codon that specifies an amino acid is mutated into a codon that specifies a different amino acid. Codons give us the code for _____ - ANSWER amino acids Codons are - ANSWER sequences of three nucleotides Silent mutations - ANSWER Is when a mutation is there, but does not change the normal gene function. DNA and RNA polymerase can _____ to check for mistakes/mutations. - ANSWER proofread few base pair mutation - ANSWER multiple base pairs are changed in DNA point mutation (substitution) - ANSWER gene mutation in which a single base pair in DNA has been changed Carcinogens are - ANSWER substances that cause cancer Mutagens are - ANSWER Agents in the environment that cause permanent changes in DNA; chemical or physical _____ is based on mutations. - ANSWER evolution Mutations can be - ANSWER neutral, beneficial, or harmful T/F. Mutations are spontaneous. - ANSWER True Mutations are - ANSWER changes in DNA sequence or changes in enzyme activity T/F. The lac operon is on even when there is no lactose present. - ANSWER False _______ gene produces a protein called a _____ to turn off the operon. - ANSWER regulatory; repressor lactose must be broken down into ______, then into 2 _______. - ANSWER disaccharides; monosaccharides The lac operon in E. coli - ANSWER the repressor protein binds to the operator in the absence of lactose; prevents lactose-utilizing enzymes from being expressed when lactose is absent from the environment T/F. The following sequence is the correct sequence for gene expression. promoter ------ regulator ------ genes ------ operator - ANSWER False Which region would be considered the operon?? regulator ----- promoter ------ operator----- genes - ANSWER promoter------operator----genes The operator can be compared to ____. - ANSWER a light switch turning on bulbs (genes); can have all "bulbs" on or off at once. DNA polymerase - ANSWER An enzyme that catalyzes the elongation of new DNA at a replication fork by the addition of nucleotides to the existing chain. structural genes - ANSWER genes that code for proteins regulatory genes - ANSWER Genes that are involved in controlling the expression of genes by repressing or activating gene. promoter - ANSWER region of DNA that indicates to an enzyme, specifically DNA polymerase, where to bind to make RNA Consticutive genes - ANSWER genes that are not regulated and are expressed at a fixed rate T/F. All genes are regulated. - ANSWER False; 60-80% of genes are not regulated operator - ANSWER region of chromosome in an operon to which the repressor binds when the operon is "turned off" operon - ANSWER A unit of genetic function common in bacteria and phages, consisting of coordinately regulated clusters of genes with related functions. How do bacteria adapt so quickly to their environment?? - ANSWER through gene expression poly-A tail - ANSWER Modified end of the 3' end of an mRNA molecule consisting of the addition of some 50 to 250 adenine nucleotides. 5' cap - ANSWER a modified form of guanine nucleotide added onto the 5' end of a pre-mRNA molecule RNA splicing is carried out by - ANSWER spliceosomes, consist of proteins and small RNAs After introns have been cut out of RNA molecules, the remaining pieces called __________ are spliced together. - ANSWER exons Exons are - ANSWER coding regions Introns are - ANSWER noncoding DNA sequences The coding regions of a gene are called - ANSWER exons RNA splicing - ANSWER The removal of noncoding portions (introns) of the RNA molecule after initial synthesis. In eukaryotes, the mRNA must go through _____ before use. - ANSWER transcription In prokaryotes, mRNA is ______ immediately. - ANSWER ready to use Prokaryotes are classified into - ANSWER Domain Bacteria and Domain Archaea Sickle cell is an example of a _______ mutation. - ANSWER missense Translation - ANSWER Process by which mRNA is decoded and a protein is produced Syndrome - ANSWER A group of symptoms typical of a particular disease or condition Transcription - ANSWER (genetics) the organic process whereby the DNA sequence in a gene is copied into mRNA communicable disease - ANSWER a disease that is spread from one host to another examples of signs - ANSWER fever, swelling, rash, pus formation contagious disease - ANSWER a type of communicable disease that spreads quickly from person to person Signs - ANSWER changes in a body that can be measured or observed as a result of disease noncommunicable disease - ANSWER a disease that is not transmitted from one host to another examples of symptoms - ANSWER pain, dizziness, itching, nausea Example of a noncommunicable disease - ANSWER tetanus symptoms - ANSWER Subjective characteristics of disease felt only by the patient