Microbial Metabolism and Sporulation Quiz
33 Questions
1 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

Which type of microorganism uses light as both an energy and carbon source?

  • Photoautotrophs (correct)
  • Anaerobic bacteria
  • Chemoautotrophs
  • Chemoheterotrophs

What is the primary carbon source for chemoautotrophs?

  • Sugars and amino acids
  • Simple organic compounds
  • Light energy
  • CO2 (correct)

Which organisms are categorized as photoheterotrophs?

  • Ammonia-oxidizing bacteria
  • Cyanobacteria
  • Nitrobacter
  • Some green or purple photosynthetic bacteria (correct)

Which energy source do chemoheterotrophs primarily rely on?

<p>Oxidation of an organic compound (C)</p> Signup and view all the answers

Which of the following is NOT a characteristic of chemoautotrophs?

<p>Being pathogenic to humans (C)</p> Signup and view all the answers

What is the first step in the process of sporulation?

<p>Formation of an axial filament of nuclear material (B)</p> Signup and view all the answers

Which of the following occurs last in the sporulation process?

<p>Destruction of the sporangium by lytic enzymes (D)</p> Signup and view all the answers

What is formed during the formation of the cortex in sporulation?

<p>Dipicolinic acid and calcium (D)</p> Signup and view all the answers

What happens to the sporangium after the spore matures?

<p>It is destroyed by lytic enzymes (D)</p> Signup and view all the answers

What triggers the process of sporulation in bacteria?

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

What is the minimum pressure experienced in land conditions?

<p>1 bar (C)</p> Signup and view all the answers

What happens to bacterial growth when water is not sufficiently available?

<p>Bacterial growth stops, but bacteria can still survive. (A)</p> Signup and view all the answers

What is the water activity ($a_w$) equation used to represent water availability?

<p>$a_w = rac{P_{sol}}{P_{eau}}$ (C)</p> Signup and view all the answers

Which of these bacteria are classified as neutrophils based on their optimal growth pH range?

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

What environmental factors can limit bacterial growth?

<p>High pressure, low temperature, and low nutrient content (D)</p> Signup and view all the answers

What is the effect of high salt concentrations on sensitive bacteria?

<p>They are inhibited by high salt concentrations. (B)</p> Signup and view all the answers

Which type of bacteria can tolerate moderate salt concentrations?

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

How does high osmotic pressure affect a bacterial cell?

<p>It inhibits growth by moving the plasma membrane away from the cell wall. (B)</p> Signup and view all the answers

What is the primary purpose of adding salts to a solution in terms of osmotic pressure?

<p>To increase osmotic pressure, aiding in food preservation. (A)</p> Signup and view all the answers

Which classification of bacteria is known to thrive in high salt concentrations?

<p>Halophile Bacteria (B)</p> Signup and view all the answers

What is the final electron acceptor in aerobic respiration?

<p>Molecular oxygen (B)</p> Signup and view all the answers

Which process generates the most ATP per glucose molecule?

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

What distinguishes anaerobic respiration from aerobic respiration?

<p>The final electron acceptor being an inorganic molecule other than oxygen (A)</p> Signup and view all the answers

What is the overall reaction formula for aerobic respiration?

<p>$C_{6}H_{12}O_{6} + 6O_{2} ightarrow 6CO_{2} + 6H_{2}O + 38ATP$ (B)</p> Signup and view all the answers

What is the role of ATP in cellular respiration?

<p>It stores energy released during oxidation of glucose (C)</p> Signup and view all the answers

What is the optimum growth temperature range for psychrophiles?

<p>10°C to 15°C (B)</p> Signup and view all the answers

Which type of microorganisms primarily contribute to food spoilage?

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

What is the temperature range within which mesophiles can grow?

<p>10°C to 50°C (D)</p> Signup and view all the answers

At what temperature range do thermophiles typically grow?

<p>40°C to 70°C (D)</p> Signup and view all the answers

What is the maximum temperature limit for hyperthermophiles?

<p>110°C (D)</p> Signup and view all the answers

Which group of microorganisms grow optimally at temperatures between 55°C and 65°C?

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

What is the minimum growth temperature for psychrotrophs?

<p>0°C (B)</p> Signup and view all the answers

Which type of microorganisms can grow between -10°C and 20°C?

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

Flashcards

Aerobic Respiration

A process where cells break down glucose to produce energy in the form of ATP. This process uses oxygen as the final electron acceptor.

Anaerobic Respiration

A process where cells break down glucose to produce energy in the form of ATP. This process uses an inorganic molecule other than oxygen as the final electron acceptor.

Fermentation

A process where cells break down glucose to produce energy in the form of ATP. This process uses an organic molecule as the final electron acceptor.

What is glucose?

The molecule that is broken down in the process of cellular respiration to produce energy.

Signup and view all the flashcards

What is ATP?

The molecule that cells use as their main energy source.

Signup and view all the flashcards

Photoautotrophs

These organisms use light as their energy source and CO2 as their carbon source. Examples include cyanobacteria and many photosynthetic bacteria.

Signup and view all the flashcards

Photoheterotrophs

These organisms use light as their energy source but obtain their carbon from simple organic compounds like acetate, lactate, or pyruvate.

Signup and view all the flashcards

Chemoautotrophs

These organisms get their energy from oxidizing reduced mineral compounds like H2S, S, or NH3. They use CO2 as their carbon source.

Signup and view all the flashcards

Chemoheterotrophs

These organisms obtain both energy and carbon from organic compounds like sugars or amino acids.

Signup and view all the flashcards

Example of Chemoheterotrophs

These are pathogenic or commensal bacteria of humans, bacteria of medical interest, food contamination bacteria, and bacteria used in industry for their synthesis of vitamins or antibiotics.

Signup and view all the flashcards

Water Activity (aw)

A measure of the relative availability of water in a solution. It's expressed as a fraction of the vapor pressure of pure water at the same temperature.

Signup and view all the flashcards

Acidophile

Bacteria that thrive in environments with a low pH (acidic).

Signup and view all the flashcards

Pressure Tolerance

The range of pressure conditions that allow an organism to survive and grow.

Signup and view all the flashcards

Barophile

Bacteria that can tolerate high pressure, often found in deep sea environments.

Signup and view all the flashcards

Optimal pH Range

The range of pH values that permit optimal growth of a specific bacterium.

Signup and view all the flashcards

Sporulation

The process of a bacterium forming a resistant spore to survive harsh conditions.

Signup and view all the flashcards

Spore Tunic

The formation of a thick, protective outer layer around the spore.

Signup and view all the flashcards

Spore Germination

The process of a spore transforming back into an active bacterium.

Signup and view all the flashcards

Spore Location

The location of the spore within the bacterium.

Signup and view all the flashcards

Bacterial Growth

The increase in the number of individual bacterial cells.

Signup and view all the flashcards

Psychrophiles

These bacteria prefer cold temperatures, growing best between 10°C and 15°C.

Signup and view all the flashcards

Mesophiles

These microorganisms thrive in moderate temperatures, with an optimal growth range between 37°C and 40°C. Many common bacteria fall into this category.

Signup and view all the flashcards

Hyperthermophiles

These bacteria grow best in very hot temperatures, thriving between 85°C and 95°C.

Signup and view all the flashcards

Thermophiles

These bacteria can tolerate very high temperatures, growing best between 55°C and 65°C.

Signup and view all the flashcards

Psychrotrophs

These bacteria can grow in temperatures ranging from 0°C to 30°C, with an optimal range between 15°C and 25°C. They are often responsible for food spoilage.

Signup and view all the flashcards

Temperature range

The range of temperatures at which an organism can survive and grow.

Signup and view all the flashcards

Optimal growth temperature

The specific temperature at which an organism grows most rapidly.

Signup and view all the flashcards

Maximum growth temperature

The temperature at which an organism can no longer survive.

Signup and view all the flashcards

Salt-Sensitive Bacteria

Bacteria that are harmed by high salt levels. They prefer low salt environments.

Signup and view all the flashcards

Halotolerant Bacteria

Bacteria that can tolerate moderate salt concentrations. They can survive in slightly salty environments.

Signup and view all the flashcards

Halophile Bacteria

Bacteria that require high salt concentrations to survive. They thrive in salty environments.

Signup and view all the flashcards

Osmotic Pressure

The pressure exerted by a solution due to the concentration of solutes. It determines the movement of water across cell membranes.

Signup and view all the flashcards

How Osmotic Pressure Affects Bacteria

Osmotic pressure inhibits cell growth. When salt is added to a solution, the water is pulled out of the cell, impacting its ability to function properly.

Signup and view all the flashcards

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser