Microbiology Test 2 Flashcards
24 Questions
100 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

An organic nutrient that cannot be synthesized by an organism and must be provided is called:

  • Water
  • Trace element
  • Growth factor (correct)
  • Element
  • Micronutrient
  • An important mineral ion that stabilizes the cell membrane and ribosome is:

  • Zinc
  • Calcium
  • Magnesium (correct)
  • Iron
  • Potassium
  • The term autotroph refers to an organism that:

  • Must obtain organic compounds for its carbon needs
  • Does not need a carbon source
  • Gets energy by oxidizing chemical compounds
  • Gets energy from sunlight
  • Uses CO2 for its carbon source (correct)
  • The methanogens require environments that:

    <p>Are anaerobic with hydrogen gas and CO2</p> Signup and view all the answers

    Organisms that feed on dead organisms for nutrients are called:

    <p>Saprobes</p> Signup and view all the answers

    The movement of molecules from an area of high concentration to low concentration is called:

    <p>Diffusion</p> Signup and view all the answers

    Diffusion of water through a semi-permeable membrane is called:

    <p>Osmosis</p> Signup and view all the answers

    Bacteria living in a freshwater stream that are moved to salty seawater will:

    <p>Shrivel</p> Signup and view all the answers

    Which of the following require the cell to use energy?

    <p>Endocytosis</p> Signup and view all the answers

    An organism with a temperature growth range from 45-60 degrees C is called:

    <p>Thermophile</p> Signup and view all the answers

    The time interval from parent cell to two new daughter cells is called:

    <p>Generation time</p> Signup and view all the answers

    The phase of the bacterial growth curve in which the rate of multiplication equals the rate of cell death is called:

    <p>Stationary phase</p> Signup and view all the answers

    Growth factors are:

    <p>Cannot be synthesized by organisms</p> Signup and view all the answers

    Nutrient absorption is mediated by the:

    <p>Cell membrane</p> Signup and view all the answers

    Facilitated diffusion is limited by:

    <p>Carrier protein in the membrane</p> Signup and view all the answers

    In which condition will the cell wall protect the cell from bursting?

    <p>Hypotonic</p> Signup and view all the answers

    Aerobic respiration is an example of:

    <p>Chemoheterotrophy</p> Signup and view all the answers

    Calcium is essential for bacteria because:

    <p>Stabilizes cell wall</p> Signup and view all the answers

    In the viable plate count method, each __________ represents one __________ from the sample.

    <p>colony, cell</p> Signup and view all the answers

    The E. coli that normally live in the large intestine and produce vitamin K is:

    <p>Commensal</p> Signup and view all the answers

    Superoxide ion is toxic to strict anaerobes because they lack:

    <p>Dismutase</p> Signup and view all the answers

    Which of the following is true of passive transport?

    <p>It requires a concentration gradient</p> Signup and view all the answers

    Which of the following statements is true for all organisms?

    <p>They require growth factors</p> Signup and view all the answers

    Psychrophiles would be expected to grow:

    <p>At freezing temperature</p> Signup and view all the answers

    Study Notes

    Nutrient and Cell Requirements

    • Growth factors are organic nutrients that organisms cannot synthesize and must obtain from their environment.
    • Magnesium is an important mineral ion that stabilizes cell membranes and ribosomes.
    • Autotrophs utilize CO2 as their carbon source for growth.
    • Methanogens thrive in anaerobic environments rich in hydrogen gas and CO2.

    Organism Classification and Nutrient Interactions

    • Saprobes decompose dead organisms for nutrients.
    • Diffusion refers to the movement of molecules from areas of high concentration to low concentration.
    • Osmosis is specifically the diffusion of water across a semi-permeable membrane.
    • Freshwater bacteria exposed to salty seawater will shrivel due to osmosis.

    Energy and Transport Mechanisms

    • Endocytosis requires cellular energy for material uptake.
    • Thermophiles have optimal growth temperatures between 45-60 degrees Celsius.
    • Generation time is the interval for a parent cell to divide into two daughter cells.
    • The stationary phase of bacterial growth occurs when multiplication and cell death rates are equal.

    Cellular Structures and Functions

    • Growth factors cannot be synthesized by organisms and are essential for growth.
    • Nutrient absorption primarily occurs through the cell membrane.
    • Facilitated diffusion is limited by the availability of carrier proteins in the membrane.
    • A hypotonic environment protects cells from bursting by exerting pressure against the cell wall.

    Metabolic Pathways and Symbiotic Relationships

    • Aerobic respiration exemplifies chemoheterotrophy, where organisms obtain energy by consuming organic compounds.
    • Calcium is crucial for stabilizing the bacterial cell wall.
    • In the viable plate count method, each colony corresponds to a single species from the original sample.
    • Commensal E. coli assist in vitamin K production in the human intestines without causing harm.

    Reactive Oxygen Species and Transport Mechanisms

    • Strict anaerobes are vulnerable to superoxide ions as they lack dismutase, an enzyme to neutralize these reactive species.
    • Passive transport requires a concentration gradient for molecules to move and does not utilize energy.
    • All organisms necessitate growth factors, either for enzyme function or structural integrity.

    Temperature Preferences of Microorganisms

    • Psychrophiles are adapted to grow at or near freezing temperatures, thriving where most organisms cannot.

    Closing Remarks

    • Understanding these fundamental concepts is essential for studying microbiological growth, interaction, and metabolism.

    Studying That Suits You

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

    Quiz Team

    Description

    Test your knowledge on essential microbiology concepts with these flashcards. Each card contains key terms and their definitions, ensuring an engaging study experience focused on critical nutrients and their functions in organisms. Perfect for students preparing for Microbiology Test 2.

    More Like This

    Phenylethyl Alcohol Agar Flashcards
    16 questions
    Microbiology Flashcards: Staph Aureus
    24 questions
    Microbiology Flashcards
    45 questions

    Microbiology Flashcards

    ReputableTangent4657 avatar
    ReputableTangent4657
    Use Quizgecko on...
    Browser
    Browser