
Concept explainers
The creation of milk products such as cheeses and yogurts is dependent on the conversion by various anaerobic bacteria, including several Lactobacillus species, of lactose to glucose and galactose, ultimately producing lactic acid. These conversions are dependent on both permease and β-galactosidase as part of the lac operon. After selection for rapid fermentation for the production of yogurt, one Lactobacillus subspecies lost its ability to regulate lac operon expression [Lapierre, L., et al. (2002). J. Bacteriol. 184:928–935]. Would you consider it likely that in this subspecies the lac operon is on or off? What genetic events would likely contribute to the loss of regulation as described above?

Want to see the full answer?
Check out a sample textbook solution
Chapter 16 Solutions
Concepts of Genetics Plus Mastering Genetics with Pearson eText -- Access Card Package (12th Edition) (What's New in Genetics)
- Describe the levels of structural hierarchy for the human body, starting with the organismal level and ending with the chemical level. In addition, you should make sure you link each level to the previous level, emphasizing the structural relationships.arrow_forward9 S es Read the section "Investigating Life: In (Extremely) Cold Blood." Then, drag and drop the terms on the left to complete the concept map. Red blood cells Genes Icefishes -have mutated have colorless Oxygen have few lack encode Blood Cellular respiration consists of- contain carries is a Platelets White blood cells carries low amounts of Hemoglobin is necessary for Plasma Protein Reset.arrow_forwardPlating 50 microliters of a sample diluted by a factor of 10-6 produced 91 colonies. What was the originalcell density (CFU/ml) in the sample?arrow_forward
- Every tutor here has got this wrong, don't copy off them.arrow_forwardSuppose that the population from question #1 (data is in table below) is experiencing inbreeding depression (F=.25) (and no longer experiencing natural selection). Calculate the new expected genotype frequencies (f) in this population after one round of inbreeding. Please round to 3 decimal places. Genotype Adh Adh Number of Flies 595 Adh Adh 310 Adhs Adhs 95 Total 1000 fladh Adh- flAdn Adh fAdhs Adharrow_forwardWhich of the following best describes why it is difficult to develop antiviral drugs? Explain why. A. antiviral drugs are very difficult to develop andhave no side effects B. viruses are difficult to target because they usethe host cell’s enzymes and ribosomes tometabolize and replicate C. viruses are too small to be targeted by drugs D. viral infections usually clear up on their ownwith no problemsarrow_forward
- This question has 3 parts (A, B, & C), and is under the subject of Nutrition. Thank you!arrow_forwardThey got this question wrong the 2 previous times I uploaded it here, please make sure it's correvct this time.arrow_forwardThis question has multiple parts (A, B & C), and under the subject of Nutrition. Thank you!arrow_forward
- Calculate the CFU/ml of a urine sample if 138 E. coli colonies were counted on a Nutrient Agar Plate when0.5 mls were plated on the NA plate from a 10-9 dilution tube. You must highlight and express your answerin scientific notatioarrow_forwardDon't copy off the other answer if there is anyarrow_forwardAnswerarrow_forward
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage LearningBiology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage LearningHuman Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning
- Biology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning




