Cell Death Mechanisms Quiz
40 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 structural feature is preserved in coagulative necrosis after injury?

  • Cytoplasmic organelles
  • Nuclear structure
  • Cell membrane integrity
  • Tissue architecture (correct)

    • What is a characteristic texture of tissues affected by coagulative necrosis?

  • Firm and dense (correct)
  • Crumbly and dry
  • Liquid and fluid
  • Soft and gelatinous

    • What primarily limits the proteolysis of dead cells in coagulative necrosis?

  • Recruitment of lymphocytes
  • Enzymatic activity increases
  • Denaturation of proteins (correct)
  • Cellular autophagy

    • Which process ultimately leads to the digestion of dead cells in coagulative necrosis?

    <p>Lysosomal enzyme activity</p> Signup and view all the answers

    What is the primary cause of coagulative necrosis in solid organs?

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

    Which type of necrosis can only be detected microscopically?

    <p>Fibrinoid necrosis</p> Signup and view all the answers

    What happens to anucleate cells in coagulative necrosis over time?

    <p>They persist for weeks</p> Signup and view all the answers

    Which of the following is NOT a feature of coagulative necrosis?

    <p>Presence of nuclear remnants</p> Signup and view all the answers

    What type of cellular injury primarily leads to increased membrane permeability?

    <p>Most forms of cell injury</p> Signup and view all the answers

    Which of the following is NOT a cause of membrane damage?

    <p>Excessive RNA synthesis</p> Signup and view all the answers

    Lysosomal membrane injury results in the leakage of which type of enzymes?

    <p>Acid hydrolases</p> Signup and view all the answers

    What is a consequence of plasma membrane damage?

    <p>Loss of osmotic balance</p> Signup and view all the answers

    Which cellular component's injury leads to irreversible damage and necrosis?

    <p>Lysosomal enzymes</p> Signup and view all the answers

    Which of the following proteins is associated with the activation of caspases?

    <p>BH3 proteins</p> Signup and view all the answers

    What triggers protein synthesis in response to endoplasmic reticulum stress?

    <p>Adaptive unfolded protein response</p> Signup and view all the answers

    What is a key feature of most types of necrosis?

    <p>Increased membrane permeability</p> Signup and view all the answers

    What is apoptosis primarily known for?

    <p>Eliminating cells with intrinsic abnormalities</p> Signup and view all the answers

    What distinguishes necrosis from apoptosis?

    <p>Apoptosis does not involve inflammation</p> Signup and view all the answers

    Which of the following occurs first after cell death?

    <p>Electron microscopy reveals cell death</p> Signup and view all the answers

    What are the consequences of necrosis?

    <p>Cell membranes lose integrity and enzymes leak</p> Signup and view all the answers

    What role do leukocytes play in necrosis?

    <p>They digest dead cells and initiate repair</p> Signup and view all the answers

    Under what circumstances does apoptosis occur?

    <p>In healthy tissue to maintain cell numbers</p> Signup and view all the answers

    What type of stimuli can lead to necrosis?

    <p>Multiple injurious stimuli</p> Signup and view all the answers

    What happens to dead cell fragments during apoptosis?

    <p>They are aggressively broken down by enzymes</p> Signup and view all the answers

    How long can skeletal muscle in the leg typically survive complete ischemia?

    <p>2 to 3 hours</p> Signup and view all the answers

    What may signal cell death by apoptosis in a starved cell?

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

    What is one of the primary ways that cell injury occurs?

    <p>Functional abnormalities in essential cellular components</p> Signup and view all the answers

    What is the role of autophagic vacuoles in infected cells?

    <p>Form around microbes leading to their destruction</p> Signup and view all the answers

    Individuals with variants in genes encoding cytochrome P-450 may:

    <p>Catabolize toxins at different rates</p> Signup and view all the answers

    What is a significant challenge in preventing cell injury?

    <p>Targeting an individual pathway</p> Signup and view all the answers

    Which of the following statements is NOT true about cell injury?

    <p>Ischemia has no effect on cellular functions.</p> Signup and view all the answers

    What primarily triggers apoptosis in cells under stress?

    <p>Damage to DNA</p> Signup and view all the answers

    What is oxidative stress primarily caused by?

    <p>The accumulation of reactive oxygen species (ROS)</p> Signup and view all the answers

    Which of the following statements about reactive oxygen species (ROS) is true?

    <p>They can induce cellular damage.</p> Signup and view all the answers

    What role does the enzyme superoxide dismutase (SOD) play regarding reactive oxygen species?

    <p>It assists in the conversion of H2O2 into less harmful substances.</p> Signup and view all the answers

    What is the consequence of hydroxyl radicals being produced in the presence of metals like Fe2+?

    <p>They increase the reactivity of H2O2, forming hydroxyl radicals.</p> Signup and view all the answers

    What process do phagocytic leukocytes utilize to produce reactive oxygen species during inflammation?

    <p>The respiratory burst</p> Signup and view all the answers

    How does ionizing radiation contribute to the production of reactive oxygen species?

    <p>By hydrolyzing water into hydroxyl and hydrogen free radicals</p> Signup and view all the answers

    In the context of phagocytic cells, what role does hydrogen peroxide (H2O2) play?

    <p>It serves as a weapon against ingested microbes.</p> Signup and view all the answers

    What is a consequence of the damage caused by free radicals to cellular components?

    <p>Disruption of nucleic acids, proteins, and lipids</p> Signup and view all the answers

    Study Notes

    Cell Death Mechanisms

    • Discovery of regulated cell death highlighted that cell death can be an intentional and controlled process.
    • Apoptosis is a type of programmed cell death that eliminates cells with intrinsic abnormalities without triggering inflammation.
    • Necrosis represents uncontrolled cell death characterized by cell membrane rupture, leading to enzyme leakage and an inflammatory response.

    Apoptosis vs. Necrosis

    • Apoptosis occurs in both pathological conditions and healthy tissues, aiding in processes like development and maintaining cellular homeostasis.
    • In necrosis, inflammation is induced due to substances released from damaged cells, helping clear debris and initiate repair.
    • Necrotic tissue exhibits distinctive morphological patterns, critical for pathology diagnosis, despite not reflecting underlying mechanisms.

    Types of Necrosis

    • Coagulative necrosis preserves tissue architecture for days post-injury, resulting in firm-textured affected areas.
    • Indicative of infarcts caused by ischemia, this type limits proteolysis due to protein denaturation.
    • Fibrinoid necrosis can only be identified microscopically, illustrating the importance of detailed examinations.

    Cell Injury and Membrane Damage

    • Increased membrane permeability leads to necrosis, often due to reactive oxygen species (ROS), nutrient deprivation, or cytoskeletal issues.
    • Major sites of membrane damage include:
      • Mitochondrial membrane
      • Plasma membrane, affecting osmotic balance
      • Lysosomal membranes, releasing enzymes that cause irreversible damage.

    Autophagy and Ischemic Injury

    • Autophagy is a survival mechanism under stress, allowing cells to recycle components when nutrients are scarce.
    • Extensive autophagy is noted during ischemic injury and certain myopathies, potentially signaling apoptosis if the cell cannot adapt.

    Mechanisms of Cell Injury

    • Cell injury can arise from functional and biochemical irregularities in cellular components, leading to apoptosis or necrosis.
    • Oxygen and nutrient deprivation (hypoxia and ischemia) primarily disrupt energy-dependent functions.
    • Diverse extrinsic causes of cell injury trigger overlapping biochemical pathways, complicating prevention strategies.

    Oxidative Stress

    • Oxidative stress results from the accumulation of reactive oxygen species (ROS), causing cellular damage.
    • Situations contributing to ROS production include chemical exposure, radiation, aging, and inflammation.
    • ROS play a critical role in immune responses, particularly in phagocytic leukocytes, enhancing their ability to destroy pathogens.

    Role of Reactive Oxygen Species (ROS)

    • ROS are chemical species with unpaired electrons, making them highly reactive and unstable.
    • They can damage vital cellular components—nucleic acids, proteins, and lipids—leading to cellular dysfunction and death.
    • The generation of ROS occurs during inflammation and under stress conditions, particularly in leukocytes through respiratory burst mechanisms.

    Studying That Suits You

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

    Quiz Team

    Related Documents

    Robbins & Kumar Basic Pathology PDF

    Description

    Test your knowledge on the different mechanisms of cell death, including apoptosis and necrosis. Explore the processes that distinguish regulated cell death from uncontrolled cell death, and understand their implications in health and disease. This quiz will cover the various types of necrosis and their characteristics.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser