Concept explainers
Videos
To analyze:
The results of the investigation showing the relationship between gradual and sudden environmental changes on the extinction, evolution, and adaptation of the populations.
Given:
Overuse of drugs has been associated with the significant increase in drug-resistance. In the given experiment, the researchers use a serial transfer for propagating 1,255 population of Escherichia coli in gradually increasing antibiotic (rifampicin) concentration environment.
Figure A shows the increasing rifampicin concentrations which are increased suddenly, gradually and moderately.
In the figure B the results of the experiments depicting the percentage of population surviving the antibiotic conditions are shown.
Introduction:
Extinction of the organisms is by the fact of sudden changes which occur in ecosystem. Sudden changes do not allow the organism to adapt and acclimatize to the environmental conditions. Gradual changes allow the organism to get accustomed to the changes and allow it to adapt accordingly.
Explanation of Solution
The experiment involved the exposure of antibiotic to the bacteria, by two ways one gradual other sudden. Survival population after treatment with different antibiotic concentrations at different rates differed greatly.
It is very much clear from survival population numbers in the graph that a sudden increase leads to the death because of such sudden increase in antibiotic concentration.
In the case of gradual increase the bacteria survived eventually end up becoming antibiotic resistant because of the fact that the gradual increase allowed the bacteria to save and protect itself by acquiring plasmids, point mutations, and genetic recombination.
The less time in sudden increase in antibiotics made the bacterium incapable of genetic exchange and hence the bacterial population decreased in numbers considerably.
The above experiment can explain the adaptation in case of multidrug resistant (MDR) and extensively drug resistant (XDR) species of Mycobacterium tuberculosis as well as sudden extinction of dinosaurs.
Therefore, it can be concluded that the extinction and loss of organisms is due to sudden change in environmental factors whereas acclimatization is the result of gradual changes in the environmental conditions.
Want to see more full solutions like this?
Chapter 1 Solutions
Life: The Science of Biology
- Biopharmaceutics and Pharmacokinetics:Two-Compartment Model Instant Absorption Questions Calculate these : a) B1, b) B2, c) hybrid rate constant (1) d) hybrid rate constant (2) e) t1/2,dist f) t1/2,elim g) k10 h) k12 i) k21 j) initial concentration (C0) k) central compartment volume (V1) l) steady-state volume (Vss) m) clearance (CL) AUC (0→10 min) using trapezoidal rule n) AUC (20→30 min) using trapezoidal rule o) AUCtail (AUC360→∞) p) total AUC (using short cut method) q) volume from AUC (VAUC)arrow_forwardUse the Henderson-Hasselbalch equation for a propanoic acid solution (CH₂CH₂CO₂H, pK₁ = 4.874) to calculate the quotient [A-]/[HA] at three different pH values. pH = 4.479 [A-] [HA] [A-] pH = 4.874 [HA] = pH = 5.220 [A-] = [HA]arrow_forwardIn order to establish the expiration date of perishable food, growth curve data must be collected. Once the microbial load is so high that it poses a hazard to human health, the food item is no longer considered safe (expired). Generally a load of x50,000 bacteria/gram is considered unsafe. Your task is to determine the microbial growth curves for MicroYo, a new brand of yogurt. The growth is determined by sampling the yogurt and growing the bacterial isolates in broth culture which is then serially diluted by a total of x10,000 and inoculated onto standard petri plates of nutrient agar. The following colony counts are measured: Time (days) MicroYo colony count# 1 1 4 1 12 2 16 20 4 7 What day should you recommend expiring the yogurt (the last possible date before the microbial load is unsafe). 12 4 20 16arrow_forward
- 9. Chicken combs in chickens is an example where you see interactions between genes. See potential genotypes and phenotypes below. Which genotype, when mated to a rose comb chicken, will produce progeny that are 50% walnut comb and 50% pea comb? walnut (RRPP) walnut (RrPP) pea (rrPP) walnut (RRPP) walnut (RrPp) pea (rrPp) rose rose single (RRPP) (Rrpp) (rrpp)arrow_forwardDescribe a compound light microscope and its importance in microbiology (2) examples of at least two microbes viewed under a compound light microscope and their general characteristics (note: the microbes you choose do not need to be the ones outlined in the above tutorial video) and (3) at least one source you used for the information included in your infographic.arrow_forwardPrice of visit Number of visits $700 0 $600 [1 $500 2 $400 3 $300 4 00000 The Table blow gives the demand curve for doctor visits for Elena. If the price of a doctor's visit is $600, and Elena does not have health insurance, she will visit the doctor times. If Elena obtains 50% coinsurance (the company pays 50% of the medical bill, Elena pays 50%), then Elena will visit the doctor times. 1; 2 0; 3 0; 2 1;4 2; 1arrow_forward
- P 200 150- 100 50 w/instrance/ w/insurance 2 100 Demand Assume that the white curve (labeled "Demand") represents an individual's true demand for this particular health care service. The coinsurance associated with insurance option 1 (in blue) is likely _. 0000 100% 25% 50% 0%arrow_forwardUse the figure below. Bob and Nancy have the same income and total utility.. willingness to pay for an insurance premium will be lower than because they are. risk- averse. Total utility Current utility Bob's utility Nancy's utility 0000 Bob; Nancy; less Nancy; Bob; less Nancy; Bob; more Bob; Nancy; more Current Income incomearrow_forwardConsider the figure below. Suppose the true price of a health care service is P1. Suppose further that the individual has obtained insurance that has a fixed copayment for this particular service. The copayment is represented by price P2. represents the quantity of the service the individual would consume without insurance. quantity of the service the individual would consume with the insurance. Health Care Service represents the P. P₂ a Q1;Q2 Q2; Q3 Q1; Q3 Q3; Q1 Q2; Q1 फ f Q ८ g d h Q3\D 7Q 00000arrow_forward
- The table shows the utility Jordan receives at various income levels, but they do not know what their income will be next year. There is a 15% chance their income will be $25,000, a 20% chance their income will be $35,000, and a 65% chance their income will be $45,000. We know that Jordan is Income $25,000 Utility 2,800 30,000 3,200 35,000 3,500 40,000 3,700 45,000 3,800 ☐ none of the above 0 000 risk taker (lover) because their marginal utility of income is increasing risk neutral because their marginal utility of income is constant risk averse because their marginal utility of income is decreasing risk neutral because their marginal utility of income is decreasingarrow_forwardOOOO a d+e d a+b+c Consider the figure below. Suppose the true price of a health care service is P1. Suppose further that the individual has obtained insurance that has a fixed copayment for this particular service. The copayment is represented by price P2. The social loss from moral hazard if the individual has copayment P2 is represented graphically by the area(s): Health Care Service P. a No 4 ८ e g Q2 Q3 Darrow_forwardOOO O The table shows the utility Jordan receives at various income levels, but they do not know what their income will be next year. There is a 15% chance their income will be $25,000, a 20% chance their income will be $35,000, and a 65% chance their income will be $45,000. We know that Jordan's expected income is. Their utility from their expected income is_ Income $25,000 Utility 2,800 30,000 3,200 35,000 3,500 40,000 3,700 45,000 3,800 $45,000; 3,800 $40,000; 3,700 $25,000; 2,800 $35,000; 3,500 $30,000; 3,200arrow_forward
Biology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning
Concepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax College
Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning
Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStax
Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning