Metabolism and Enzymes Quiz
48 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary purpose of enzymes in metabolism?

  • To alter the substrates
  • To create energy
  • To become part of the end products
  • To increase the rate of chemical reactions (correct)

Which statement best describes anabolism?

  • It is energy-releasing.
  • It breaks down macromolecules.
  • It builds up macromolecules. (correct)
  • It only occurs in the presence of oxygen.

What effect does denaturation have on enzymes?

  • It increases their catalytic activity.
  • It distorts the enzyme's shape and inhibits function. (correct)
  • It allows substrates to bind more easily.
  • It transforms them into coenzymes.

Which type of enzymes are present in constant amounts within a cell?

<p>Constitutive enzymes (D)</p> Signup and view all the answers

What is the final electron acceptor in aerobic respiration?

<p>Oxygen (C)</p> Signup and view all the answers

What happens during glycolysis?

<p>Glucose is oxidized into two molecules of pyruvic acid. (A)</p> Signup and view all the answers

Which process occurs when oxygen is not required for glucose oxidation?

<p>Fermentation (C)</p> Signup and view all the answers

What is primarily generated in the Kreb's Cycle?

<p>NADH and ATP (A)</p> Signup and view all the answers

What is the primary goal of antimicrobial chemotherapy?

<p>To eliminate the infectious agent without affecting the host's cells (A)</p> Signup and view all the answers

Which of the following antibiotics is known for its narrow spectrum of activity?

<p>Penicillin G (B)</p> Signup and view all the answers

How do polymyxins primarily exert their effect against bacteria?

<p>By interacting with membrane phospholipids (B)</p> Signup and view all the answers

Which antibiotic is effective against gram-positive cells?

<p>Daptomycin (C)</p> Signup and view all the answers

What is the action of tetracyclines in antimicrobial therapy?

<p>Binding to ribosomes to block protein synthesis (B)</p> Signup and view all the answers

What is the main mode of action for sulfonamides in treating bacterial infections?

<p>Blocking synthesis of folic acid (D)</p> Signup and view all the answers

What is the primary role of catabolic processes in cells?

<p>To provide energy for complex building reactions (B)</p> Signup and view all the answers

Which of the following antibiotics disrupts nucleic acids by blocking RNA polymerase?

<p>Rifampin (D)</p> Signup and view all the answers

Which nutrient is essential for protein synthesis and membrane function?

<p>Potassium $(K)$ (C)</p> Signup and view all the answers

Ivermectin is primarily used to treat which type of infection?

<p>Round worm infections and lice (C)</p> Signup and view all the answers

Which type of microbe obtains its carbon from organic forms?

<p>Heterotroph (A)</p> Signup and view all the answers

During beta oxidation, what do fatty acids get converted into that can enter the Krebs cycle?

<p>Acetyl CoA (D)</p> Signup and view all the answers

What is the primary function of reverse transcriptase in retroviruses like HIV?

<p>Reversing RNA to DNA (B)</p> Signup and view all the answers

What role do MDR pumps play in bacterial resistance?

<p>They export drugs out of the cell (B)</p> Signup and view all the answers

What happens to amino groups during the deamination process?

<p>They are excreted as ammonia (B)</p> Signup and view all the answers

What percentage of infections involve biofilms?

<p>60% (D)</p> Signup and view all the answers

Which of the following elements is important for maintaining the structure of proteins?

<p>Zinc $(Zn)$ (B)</p> Signup and view all the answers

Which of the following is NOT considered a major side effect of antimicrobial drugs?

<p>Enhanced microbial growth (C)</p> Signup and view all the answers

What characterizes a chemotroph?

<p>It derives energy from chemical reactions (C)</p> Signup and view all the answers

What does the minimum inhibitory concentration (MIC) refer to?

<p>The smallest effective concentration to inhibit growth (C)</p> Signup and view all the answers

In a hypertonic solution, what occurs to a bacterial cell?

<p>Water diffuses out of the cell, causing it to shrink (D)</p> Signup and view all the answers

Superinfection is characterized by which of the following?

<p>An infection caused by overgrowth of drug-resistant organisms (B)</p> Signup and view all the answers

What could cause antimicrobial treatment to fail?

<p>The pathogen is mixed with resistant strains (A)</p> Signup and view all the answers

What is the main characteristic of drugs that cause disruption of the body's microbiota?

<p>They alter microbial balance (B)</p> Signup and view all the answers

What is the primary characteristic of the death phase in microbial growth?

<p>There is a permanent loss of reproductive capacity. (C)</p> Signup and view all the answers

Which method is used for direct cell count in microbial analysis?

<p>Flow cytometer (C)</p> Signup and view all the answers

What is the purpose of bacteriostatic agents?

<p>They prevent the growth of bacteria. (A)</p> Signup and view all the answers

Which statement accurately describes sanitization?

<p>It cleanses to remove debris, soil, and toxins. (C)</p> Signup and view all the answers

What is a common characteristic of moist heat sterilization compared to dry heat?

<p>It is more effective at lower temperatures. (A)</p> Signup and view all the answers

What is the function of surfactants in microbial control?

<p>They lower surface tension of cell membranes. (D)</p> Signup and view all the answers

What best describes microbistasis?

<p>It prevents microbial multiplication without killing microbes. (A)</p> Signup and view all the answers

Which of the following methods is considered to have the highest resistance to decontamination?

<p>Bacterial endospores (B)</p> Signup and view all the answers

What is the thermal death time?

<p>The time required to kill microbes at a specific temperature (A)</p> Signup and view all the answers

What is the definition of thermal death point?

<p>The lowest temperature required to kill all microbes in a sample in 10 minutes (D)</p> Signup and view all the answers

What is the primary goal of pasteurization?

<p>To kill potential agents of infection while retaining flavor (D)</p> Signup and view all the answers

Which characteristic applies to nonionizing radiation?

<p>It raises atoms to a higher energy state without ionizing them (C)</p> Signup and view all the answers

What is the mechanism of action for alcohol in disinfecting?

<p>Inactivates enveloped viruses more readily than nonenveloped ones (B)</p> Signup and view all the answers

What distinguishes glutaraldehyde in its application?

<p>It is labeled as a sterilant and high-level disinfectant (D)</p> Signup and view all the answers

What is a unique property of ethylene oxide (ETO)?

<p>It reacts with functional groups of DNA and proteins (A)</p> Signup and view all the answers

Which factor reduces the activity of quaternary ammonium compounds?

<p>Presence of organic matter (C)</p> Signup and view all the answers

Flashcards

Metabolism

All chemical reactions in an organism that are necessary to maintain life

Anabolism

Building up of complex molecules from simpler ones, requiring energy

Catabolism

Breaking down complex molecules into simpler ones, releasing energy

Enzymes

Biological catalysts that speed up chemical reactions without being consumed

Signup and view all the flashcards

Cofactors

Non-protein molecules that assist enzymes in their function

Signup and view all the flashcards

Denaturation

Disruption of an enzyme's shape, preventing its function

Signup and view all the flashcards

Glycolysis

The breakdown of glucose into pyruvate, producing ATP and reducing power

Signup and view all the flashcards

Electron Transport Chain (ETC)

A series of membrane-bound proteins that transfer electrons to generate ATP

Signup and view all the flashcards

Thermal Death Time

The shortest time required to kill all microbes at a specific temperature.

Signup and view all the flashcards

Thermal Death Point

The lowest temperature needed to kill all microbes in a sample within 10 minutes.

Signup and view all the flashcards

Pasteurization

A heat treatment for liquids that kills harmful microbes while preserving flavor and food value.

Signup and view all the flashcards

Irradiation

Using radiant energy for sterilization, disinfection, or therapy.

Signup and view all the flashcards

Ionizing Radiation

Radiation that ejects electrons from atoms, creating ions.

Signup and view all the flashcards

Nonionizing Radiation

Radiation that excites atoms but doesn't create ions, like ultraviolet light.

Signup and view all the flashcards

Filtration Sterilization

A technique for removing microbes from air or liquids by passing them through a filter.

Signup and view all the flashcards

Intermediate-level Germicides

Chemicals that kill fungal spores, resistant pathogens, and viruses, but not bacterial spores.

Signup and view all the flashcards

Selective Toxicity

The ability of antimicrobial drugs to harm microbes without damaging host tissues.

Signup and view all the flashcards

Peptidoglycan

A rigid structure in bacterial cell walls that protects them from bursting in hypotonic environments.

Signup and view all the flashcards

How do Polymyxins work?

They interact with membrane phospholipids, causing leakage of proteins and nucleic acids, particularly in gram-negative bacteria.

Signup and view all the flashcards

What does Daptomycin do?

Shows selectivity for gram-positive cells.

Signup and view all the flashcards

Antimicrobial drugs and nucleic acid synthesis

They interfere with nucleic acid synthesis by blocking nucleotide synthesis, inhibiting replication, or stopping transcription.

Signup and view all the flashcards

Antimicrobial drugs and protein synthesis

Most drugs that inhibit protein synthesis react with the ribosome-mRNA complex.

Signup and view all the flashcards

Sulfonamide's action

They are antimicrobial drugs that interfere with the essential metabolic process of bacteria and some fungi by blocking synthesis of folic acid.

Signup and view all the flashcards

Ivermectin's action

It's a broad-spectrum antiparasitic used to treat roundworm infection and lice, and works by blocking viral penetration, replication, transcription, and/or translation, or preventing viral particle maturation.

Signup and view all the flashcards

Stationary Phase

A phase in bacterial growth where the number of new cells produced equals the number of cells dying, resulting in no net increase in population.

Signup and view all the flashcards

Death Phase

A phase in bacterial growth where the number of cells dying exceeds the number of new cells being produced, leading to a decrease in population.

Signup and view all the flashcards

Direct Cell Count

A method of measuring the number of bacteria in a sample using a microscope to directly count the cells within a specific volume.

Signup and view all the flashcards

Coulter Counter

An electronic device that measures cell numbers in a sample by passing the fluid through a tiny opening and detecting changes in electrical resistance as cells pass through.

Signup and view all the flashcards

Flow Cytometer

A device similar to a Coulter counter but can also differentiate between live and dead cells and measure their size based on light scattering.

Signup and view all the flashcards

Sterilization

The process that completely eliminates all viable microorganisms, including the most resistant forms, like bacterial spores.

Signup and view all the flashcards

Microbistasis

A state where microorganisms are temporarily prevented from multiplying but not killed.

Signup and view all the flashcards

Disinfection

The process of killing vegetative pathogens (bacteria, viruses, fungi) but not bacterial spores using physical methods or chemical agents.

Signup and view all the flashcards

Beta Oxidation

The process of breaking down fatty acids into acetyl CoA, which can then enter the Krebs cycle.

Signup and view all the flashcards

Deamination

The removal of an amino group (NH2) from an amino acid, producing ammonia (NH3) and a keto acid.

Signup and view all the flashcards

Continuous Biosynthesis

Bacteria constantly synthesize their components, using building blocks from the environment.

Signup and view all the flashcards

Catabolism in Non-dormant Cells

Catabolic processes occur even when nutrients are present, as long as the cell is not dormant.

Signup and view all the flashcards

Catabolism provides Energy for Anabolism

Energy released from breaking down molecules (catabolism) is used for building up complex molecules (anabolism).

Signup and view all the flashcards

Heterotroph

A microbe that obtains its carbon from organic sources, such as sugars or proteins.

Signup and view all the flashcards

Autotroph

A microbe that uses inorganic CO2 as its carbon source.

Signup and view all the flashcards

Phototroph

A microbe that gets its energy from sunlight through photosynthesis.

Signup and view all the flashcards

Reverse Transcriptase

An enzyme used by retroviruses, like HIV, to convert RNA into DNA. This process is called reverse transcription.

Signup and view all the flashcards

Interferon

A protein produced by cells in response to viral or bacterial infections. Interferons help defend against infection by signaling other cells to produce antiviral proteins.

Signup and view all the flashcards

Drug Resistance

The ability of microorganisms to survive and multiply in the presence of a drug that would normally kill them.

Signup and view all the flashcards

Multi-Drug Resistant (MDR) pumps

Proteins found in some bacteria that actively pump out antibiotics and other toxins, preventing them from reaching their targets.

Signup and view all the flashcards

Biofilms

A complex community of microorganisms growing within an extracellular matrix, often found in infections.

Signup and view all the flashcards

Major side effects of drugs

Direct damage to tissues due to toxicity, allergic reactions, and disruption of the body's microbiota.

Signup and view all the flashcards

Superinfection

An infection that develops during antimicrobial therapy, caused by an overgrowth of drug-resistant microorganisms.

Signup and view all the flashcards

Kirby-Bauer Technique

A laboratory test used to determine the susceptibility of bacteria to antibiotics. It involves spreading bacteria on an agar plate and placing antibiotic discs near the bacteria.

Signup and view all the flashcards

Study Notes

Chapter 8 Notes

  • Metabolism is the sum of all chemical reactions in the body needed for homeostasis.
  • Two types of metabolism exist:
    • Anabolism: building up of macromolecules for structural components and functions.
    • Catabolism: breaking down of macromolecules to produce energy.
  • Enzymes are biological catalysts that speed up chemical reactions by lowering activation energy.
  • Enzymes are not consumed or altered in the process.
  • Cofactors assist enzymes, including coenzymes (often derived from vitamins).
  • Denaturation occurs when weak bonds maintaining an enzyme's shape are broken, and the enzyme loses its function.
  • Constitutive enzymes are present in constant amounts, while the concentration of regulated enzymes responds to substrate levels.
  • Enzyme synthesis can be controlled through induction or repression.
  • Energy is mainly stored as ATP.
  • Oxidation-reduction (redox) reactions pair an electron donor with an acceptor, releasing and capturing energy.

Chapter 8 Notes (continued)

  • Metabolism uses enzymes to break down organic molecules into precursor molecules that cells use to build more complex molecules.
  • Three main metabolic pathways are glycolysis, the Krebs cycle, and the respiratory chain (electron transport and oxidative phosphorylation).
  • Aerobic respiration requires oxygen; anaerobic respiration uses other oxidized compounds; and fermentation does not require oxygen.
  • Glycolysis converts glucose into pyruvic acid, generating ATP and NADH.
  • Complex polysaccharides are broken into simple sugars that enter the glycolysis pathway.
  • Lipids are broken down by lipases into fatty acids, which are further processed into acetyl CoA to enter the Krebs cycle.
  • Proteins are broken down by proteases into amino acids, which then undergo deamination.
  • Catabolic processes provide energy for complex building reactions.

Chapter 7 Notes

  • Bioelements (essential nutrients): elements necessary for living things.
  • Macronutrients: needed in large quantities for structure and metabolism (e.g., carbon, hydrogen, oxygen).
  • Micronutrients (trace elements): needed in small amounts for enzyme function and protein structure (e.g., potassium, magnesium, iron).
  • Organic nutrients contain carbon and hydrogen; inorganic nutrients do not.
  • Various elements play crucial roles in cell processes and transport.

Chapter 7 Notes (continued)

  • Carbon sources:
    • Heterotrophs obtain carbon from organic sources.
    • Autotrophs use inorganic carbon dioxide (CO2).
  • Energy sources:
    • Phototrophs obtain energy from light.
    • Chemotrophs obtain energy from chemical compounds.
  • Microbial growth temperature:
    • Minimum temperature: lowest temperature for growth.
    • Maximum temperature: highest temperature for growth.
    • Optimum temperature: best temperature for fastest growth.
    • Psychrophiles thrive in cold temperatures; psychrotrophs can grow at refrigerator temperatures; mesophiles thrive in moderate temperatures; thermophiles thrive in high temperatures.
  • Factors affecting microbial growth:
    • Aerobes require oxygen; anaerobes do not; facultative anaerobes can use oxygen or not.
    • Microaerophiles require moderate oxygen levels.
    • Aerotolerant anaerobes do not use oxygen, but can survive in its presence.
    • Acidophiles prefer acidic environments; alkaliphiles prefer alkaline environments.
    • Osmophiles prefer high salt concentrations; halophiles require high salt concentrations; halotolerant/osmotolerant organisms can withstand some salt.
    • Biofilms: microbial communities attached to surfaces.

Chapter 7 Notes (continued)

  • Bacterial growth:
    • Binary fission: one cell divides into two.
    • Generation time (doubling time): time for one cell to divide into two.
    • Growth curve: lag phase, log phase, stationary phase, death phase.
    • Methods for microbial counting: viable cell counts, direct counts.

Chapter 11 Notes

  • Contamination: unwanted microbes in a place or time.
  • Decontamination methods: physical or chemical agents.
  • Microbial resistance levels: high, moderate, low.
  • Sterilization: complete elimination of all viable microbes, including spores.
  • Disinfection: destroying/removing pathogens on inanimate surfaces.
  • Antiseptics: disinfectants for living tissue.
  • Sanitization: reducing microbes to safe levels.
  • Mechanisms of microbial action: chemicals and physical agents.
  • Surfactants and their effect on microbes.

Chapter 11 Notes (continued)

  • Halogens: effective disinfectants and antiseptics, including chlorine and iodine (most often used).
  • Alcohols: effective against vegetative forms of bacteria and viruses, but not spores.
  • Hydrogen peroxide: its germicidal effect is due to the formation of hydroxyl free radicals.
  • Glutaraldehyde: a strong alkylating agent that is effective against a broad spectrum of organisms.
  • Ethylene oxide (ETO): a strong alkylating agent that is used as a sterilant.
  • Quaternary ammonium compounds: disinfectants effective against a broad spectrum of organisms, but their activity is decreased by organic material.
  • Filtration: a physical method of removing microbes from air or liquids.

Chapter 12 Notes

  • Antimicrobial chemotherapy goal: destroy infectious agent without harming host cells.
  • Antibiotics: substances from microorganisms that inhibit or kill other microorganisms.
  • Selective toxicity: effective against the infectious agent but not the host.
  • Cell walls: peptidoglycan protects bacteria and serves as a target for some antimicrobial drugs (like penicillin).
  • Antimicrobials affecting nucleic acids: blocking synthesis, replication, transcription and preventing normal maturation.
  • Antimicrobials affecting protein synthesis: interfering with ribosomes and the machinery of protein synthesis.
  • Drug resistance: some microbes develop resistance to antimicrobial drugs through various mechanisms, including mutations, drug pumps and adaptive responses.

Chapter 12 Notes (continued)

  • Side effects of antimicrobial drugs:
    • Toxicity: direct damage to host tissues.
    • Allergic reactions: immune responses.
    • Disruption of normal microbiota: can lead to superinfections.
    • Methods of determining drug susceptibility: Kirby-Bauer technique and tube dilution tests, minimum inhibitory concentration (MIC).
  • Factors contributing to antimicrobial treatment failure:
    • Resistant cells, multiple infecting pathogens, poor drug distribution to target areas.
  • Important considerations for effective treatment: considering optimal dosage, administration route and drug combination.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Chapter 8 Notes PDF

Description

Test your knowledge on the role of enzymes in metabolism, including anabolism and effects of denaturation. This quiz covers key concepts that are essential for understanding biochemical processes.

More Like This

Biochemistry Enzyme Functions and Metabolism
47 questions

Biochemistry Enzyme Functions and Metabolism

ComplimentaryGenius8542 avatar
ComplimentaryGenius8542
Use Quizgecko on...
Browser
Open
Browser
Browser