The _____ test is used for detecting chemicals with carcinogenic potential.
Koch
Ames
mutation
cancer
lowa
The Correct Answer is B
A. Koch: Koch’s postulates are criteria for linking a microorganism to a disease and are unrelated to chemical carcinogenicity testing.
B. Ames: The Ames test uses bacteria to detect mutagenic potential of chemicals; because mutagens often correlate with carcinogens, the Ames test is widely used as a screen for carcinogenic potential.
C. Mutation: Mutation is a general term for DNA changes; while mutation assays detect genetic changes, the named specific screening test commonly used for carcinogenic potential is the Ames test.
D. Cancer: “Cancer test” is not a standard name for an assay used to screen chemicals for carcinogenic potential.
E. Iowa: Iowa is a proper noun (a U.S. state) and is not the name of a chemical carcinogenicity assay.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is B
Explanation
A. Temperature and pH affect the rate of substrate binding:
Temperature and pH can influence binding rates indirectly, but this statement does not capture the primary shared mechanism by which extreme temperature or pH reduce enzyme activity.
B. Temperature and pH both induce an enzyme to lose its precise three-dimensional shape:
Both heat and extreme pH disrupt noncovalent interactions (hydrogen bonds, ionic bonds, hydrophobic interactions) that maintain tertiary and quaternary structure, causing loss of the active-site geometry and reduced catalytic activity.
C. Temperature and pH change the activation energy of the reaction:
Activation energy is an inherent property of a given catalyzed reaction; enzymes lower activation energy, but temperature and pH typically affect enzyme structure and kinetics rather than directly altering the chemical activation energy of the catalyzed step.
D. Temperature and pH change the ionization state of cofactors:
pH can change ionization states of cofactors and active-site residues; temperature less directly changes ionization state, so this does not represent a common mechanism for both.
E. There is no common mechanism of temperature and pH effects on enzyme activity:
There is a common mechanism: both can disrupt the weak bonds that maintain native protein structure, leading to loss of function.
Correct Answer is C
Explanation
A. Dry heat: Dry heat at sufficiently high temperature and long exposure (for example, 160–170 °C for prolonged periods) can destroy endospores by oxidizing cellular components, though it requires more time than moist heat.
B. Alcohol-based hand sanitizers: Alcohols are effective against many vegetative bacteria and some viruses but do not reliably destroy bacterial endospores.
C. Steam under pressure (autoclave): Autoclaving uses moist heat at high pressure and temperature (typically 121 °C at 15 psi) to reliably inactivate endospores by denaturing proteins and nucleic acids.
D. Boiling in water for 10 minutes: Boiling kills many vegetative organisms but does not reliably inactivate heat-resistant endospores within that time frame.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.