Innate Immune System Quiz
53 Questions
4 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 of the following best describes the initial interaction between a phagocyte and a pathogen during phagocytosis?

  • The phagocyte creates a phagolysosome around the pathogen.
  • The phagocyte recognizes and adheres to the pathogen or debris. (correct)
  • The phagocyte releases lysozymes to neutralize the pathogen.
  • The phagocyte immediately digests the pathogen via stomach acid.

What is the primary function of lysozyme in the context of bodily defenses?

  • To act as an antibacterial enzyme. (correct)
  • To create a physical barrier to trap microbes.
  • To increase the acidity of the digestive tract.
  • To aid in the production of mucus.

Which of these is NOT typically a cause of acute inflammation?

  • Ischemia.
  • Specific immune responses. (correct)
  • Physical damage such as burns or abrasions.
  • Allergic reactions.

What is the role of ciliated mucous membranes in the respiratory tract in the context of the body's defense mechanisms?

<p>To move trapped microorganisms to be swallowed and digested. (D)</p> Signup and view all the answers

Which of the following is a cardinal sign of acute inflammation?

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

Which of the following is NOT a typical function of the skin as a surface barrier?

<p>Secreting lysozyme to break down bacterial cell walls. (A)</p> Signup and view all the answers

Which cell type is MOST associated with the innate immune response?

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

The movement of leukocytes from blood vessels into tissues is called:

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

Which of the following is a characteristic of the first line of defense in the innate immune system?

<p>It is comprised of physical barriers such as skin and mucous membranes. (D)</p> Signup and view all the answers

Which of the following is NOT a function of mucous membranes?

<p>Producing sebum to prevent bacterial growth. (B)</p> Signup and view all the answers

Which of the following bodily fluids does NOT contain lysozyme?

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

The adaptive immune system is characterized by which of these cells?

<p>B and T cells (C)</p> Signup and view all the answers

Which of the following is an example of a second line of defense in the innate immune system?

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

Which of the following cells are part of the second line of defense in the immune system?

<p>Neutrophils (C), Macrophages (A)</p> Signup and view all the answers

What is the primary role of natural killer (NK) cells in the immune response?

<p>Attack and kill cancer or virus-infected cells (C)</p> Signup and view all the answers

How do antimicrobial proteins function in the immune system?

<p>By attacking microorganisms or inhibiting their reproduction (A)</p> Signup and view all the answers

What distinguishes the action of natural killer (NK) cells from that of other immune cells?

<p>NK cells kill cells by releasing perforins (B)</p> Signup and view all the answers

What role do interferon proteins play in the immune response?

<p>They inhibit viral replication (A)</p> Signup and view all the answers

Which statement accurately describes complement proteins?

<p>They consist of more than 20 plasma proteins in inactive form (D)</p> Signup and view all the answers

Which of the following represents the primary defensive mechanism of phagocytic white blood cells?

<p>Engulfing and digesting foreign matter (D)</p> Signup and view all the answers

What triggers inflammation as part of the immune response?

<p>The release of histamines and other chemicals (C)</p> Signup and view all the answers

What role does interferon play in the immune response?

<p>It helps protect cells from viral infection. (C)</p> Signup and view all the answers

What occurs as a result of interferon binding to a host cell?

<p>Antiviral proteins are synthesized. (D)</p> Signup and view all the answers

Which immune system components are primarily involved in adaptive immunity?

<p>T and B lymphocytes, along with antibodies. (B)</p> Signup and view all the answers

Which statement best describes innate immunity?

<p>It involves a generalized response to pathogens. (D)</p> Signup and view all the answers

How does complement contribute to the immune system?

<p>It helps destroy pathogens and enhances inflammation. (B)</p> Signup and view all the answers

What is a key feature of the adaptive immune response?

<p>It is capable of remembering previous infections. (C)</p> Signup and view all the answers

Which cells are primarily involved in regulating and coordinating immune responses?

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

What happens to the initial site of infection during an immune response?

<p>The immune system can respond beyond the initial infection site. (D)</p> Signup and view all the answers

What is the primary role of T-lymphocytes in the immune response?

<p>They kill tumor cells and virus-infected cells. (A)</p> Signup and view all the answers

Which cell type is responsible for activating B-cells and other T-cells?

<p>CD4+ T-helper cells (B)</p> Signup and view all the answers

How do Class I MHC molecules alert the immune system?

<p>By binding a peptide fragment to signal a viral infection. (A)</p> Signup and view all the answers

What function do dendritic cells serve in the immune system?

<p>They act as antigen-presenting cells. (C)</p> Signup and view all the answers

Which statement about memory lymphocytes is true?

<p>They remain in the body for a long time after an immune response. (A)</p> Signup and view all the answers

What is the primary function of macrophages in the immune response?

<p>They act as antigen-presenting cells and destroy invaders. (C)</p> Signup and view all the answers

What distinguishes major histocompatibility complex (MHC) proteins?

<p>They help the immune system differentiate between 'self' and foreign cells. (D)</p> Signup and view all the answers

Which type of T-cell interacts with MHC Class II molecules?

<p>CD4+ T-helper cells (A)</p> Signup and view all the answers

What is the role of cytokines in the immune response?

<p>Help to activate T- and B-lymphocytes. (B)</p> Signup and view all the answers

What characterizes Class I MHC molecules?

<p>They can be recognized by CD8+ T-cytotoxic cells. (C)</p> Signup and view all the answers

What is the main function of vasodilation during inflammation?

<p>To increase blood flow and cause redness (A)</p> Signup and view all the answers

Which substance is NOT a chemical mediator released during inflammation?

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

What does leukocytosis refer to?

<p>Increased number of white blood cells in the bloodstream (B)</p> Signup and view all the answers

What is chemotaxis?

<p>Movement of leukocytes towards the site of injury (B)</p> Signup and view all the answers

What results from increased capillary permeability during inflammation?

<p>Fluid leakage into tissue spaces (D)</p> Signup and view all the answers

What is diapedesis?

<p>The process of leukocytes exiting capillaries (A)</p> Signup and view all the answers

How does edema occur during inflammation?

<p>Fluid accumulation due to leaked plasma proteins (B)</p> Signup and view all the answers

Which of the following is a sign of inflammation?

<p>Swelling, redness, heat, and pain (C)</p> Signup and view all the answers

What role do neutrophils play in the inflammatory response?

<p>They phagocytize pathogens and dead cells (A)</p> Signup and view all the answers

What is the purpose of the fibrin patch formed during inflammation?

<p>To prevent further injury to surrounding tissue (B)</p> Signup and view all the answers

What is the primary cause of redness in inflamed tissues?

<p>Increased blood flow due to vasodilation (A)</p> Signup and view all the answers

Which process allows leukocytes to exit the bloodstream?

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

What contributes to the heat observed in an inflamed area?

<p>Vasodilation and increased metabolic activity (B)</p> Signup and view all the answers

What type of fluids accumulate in tissues during inflammation as a result of capillary permeability?

<p>Protein-rich exudate (D)</p> Signup and view all the answers

Flashcards

Innate Immunity

The body's first line of defense against pathogens. It consists of physical barriers like skin and mucous membranes.

Skin

The intact outer layer of skin, acting as a mechanical barrier against pathogens. Its keratin provides waterproofing and resistance to weak acids and bases.

Mucous Membranes

Protective linings found in internal body cavities, like the respiratory and digestive tracts. They produce mucus and other secretions to trap and remove pathogens.

Mucus

A sticky substance produced by mucous membranes that traps microorganisms and particles, preventing their entry into the body.

Signup and view all the flashcards

Cilia

Tiny hair-like structures found in the respiratory tract that beat rhythmically to move mucus and trapped debris out of the lungs.

Signup and view all the flashcards

Tears

Lacrimal secretions that constantly clean the eye and contain lysozyme, an antibacterial enzyme.

Signup and view all the flashcards

Saliva

Secretions from the salivary glands that help clean the oral cavity and contain lysozyme, an antibacterial enzyme.

Signup and view all the flashcards

Urine

The flow of urine through the urethra helps cleanse the lower urinary tract. The acidic pH of urine inhibits bacterial growth.

Signup and view all the flashcards

Phagocyte

A type of immune cell that engulfs and destroys harmful invaders like bacteria and debris.

Signup and view all the flashcards

Phagocytosis

A process where phagocytes engulf and digest pathogens or debris. It involves several steps: recognizing and adhering to the target, engulfing it into a phagosome, and fusing with lysosomes to form a phagolysosome for breakdown.

Signup and view all the flashcards

Inflammation

A non-specific immune response characterized by redness, swelling, heat, pain, and sometimes loss of function. It's triggered by various insults like injury, infection, or chemical irritation.

Signup and view all the flashcards

Lysozyme

Secretions like saliva, tears, and mucus contain this antibacterial enzyme that breaks down bacterial cell walls.

Signup and view all the flashcards

Acidity of Skin

The protective layer of skin, which is acidic, helps to inhibit bacterial growth.

Signup and view all the flashcards

Interferon

A type of protein released by virus-infected cells. It helps protect healthy cells from viral infection by signaling them to produce antiviral proteins.

Signup and view all the flashcards

Complement

A part of the innate immune system that works with the inflammatory response. It's a group of proteins that can directly destroy pathogens and help activate other immune cells.

Signup and view all the flashcards

Adaptive Immunity

A defense mechanism that targets very specific foreign invaders and can develop a memory of past infections, making it more effective in future encounters.

Signup and view all the flashcards

Lymphocytes

A type of white blood cell essential for adaptive immune response. They are responsible for recognizing specific antigens and mounting a targeted attack.

Signup and view all the flashcards

T lymphocytes

These cells are responsible for recognizing specific antigens and then triggering the production of antibodies or directly destroying infected cells.

Signup and view all the flashcards

B lymphocytes

A type of lymphocyte that produces antibodies, which are proteins that bind to specific antigens and neutralize them.

Signup and view all the flashcards

Antibodies

These proteins are produced by B lymphocytes and bind to specific antigens, neutralizing them and marking them for destruction by other immune cells.

Signup and view all the flashcards

Macrophages

Cells that engulf and digest pathogens and cellular debris, acting as a crucial part of both innate and adaptive immune responses.

Signup and view all the flashcards

Second Line of Defense

The innate immune system's second line of defense, activated when pathogens breach the first line, involving various mechanisms like phagocytic cells, antimicrobial proteins, inflammation, and fever.

Signup and view all the flashcards

Phagocytic Cells

White blood cells that engulf and destroy invading microorganisms, like bacteria and viruses. Examples include neutrophils, eosinophils, macrophages.

Signup and view all the flashcards

Eosinophils

A type of phagocyte that releases chemicals to kill parasites and bacteria, often seen in allergic reactions.

Signup and view all the flashcards

Natural Killer (NK) Cells

A type of phagocyte that patrols the blood and lymph, killing cancer cells, virus-infected cells, and identifying and destroying invaders without specific targeting.

Signup and view all the flashcards

Antimicrobial Proteins

Proteins that attack microorganisms directly or inhibit their reproduction, such as interferon and complement proteins.

Signup and view all the flashcards

Complement System

A group of more than 20 proteins that circulate in an inactive form, but when activated by foreign substances (like bacteria), trigger a cascade of events that leads to the destruction of the invader.

Signup and view all the flashcards

Innate defenses

The body's first line of defense against pathogens, such as skin and mucous membranes.

Signup and view all the flashcards

Internal defenses

Internal defenses are a second line of defense that act after pathogens penetrate the innate barriers. They include processes like inflammation and phagocytosis.

Signup and view all the flashcards

Vasodilation

The process of blood vessels widening, allowing for increased blood flow to the affected area, causing redness and heat.

Signup and view all the flashcards

Increased capillary permeability

The leaking of fluid from blood vessels into the surrounding tissue spaces, causing swelling.

Signup and view all the flashcards

Leukocyte migration

White blood cells migrating to the site of injury, attracted by chemical signals.

Signup and view all the flashcards

Leukocytosis

An increase in the number of white blood cells in the bloodstream, indicating an active immune response.

Signup and view all the flashcards

Margination

The process of immune cells sticking to the walls of blood vessels before exiting to the injured area.

Signup and view all the flashcards

Diapedesis

The process of white blood cells squeezing through the walls of blood vessels to reach the site of injury.

Signup and view all the flashcards

Healing

The process of healing and repair after inflammation, including tissue regeneration and scar formation.

Signup and view all the flashcards

Exudate

A protein-rich fluid leaking from blood vessels into tissue spaces, contributing to swelling and creating a scaffold for tissue repair.

Signup and view all the flashcards

Clotting proteins

A temporary fibrin patch formed at the site of injury, helping to wall off the area and prevent the spread of infection.

Signup and view all the flashcards

Chemical Mediators

Chemical messengers released from the body in response to injury or infection, playing a crucial role in inflammation and the immune response.

Signup and view all the flashcards

Area cleared of debris

The process of clearing debris and pathogens from the site of injury, crucial for successful healing.

Signup and view all the flashcards

Immunocompetent

Specialized cells that can recognize and respond to foreign invaders, while also tolerating the body's own cells. This ability is crucial for a healthy immune system.

Signup and view all the flashcards

Lymphocyte Activation

The process of lymphocytes becoming activated and ready to fight a specific antigen after encountering it for the first time. This involves cloning effector and memory cells.

Signup and view all the flashcards

Clusters of Differentiation (CD)

A group of surface molecules found on lymphocytes. These are like unique ID tags that help differentiate between different types of lymphocytes, each with its own specific role in immunity.

Signup and view all the flashcards

CD4+ T-Helper Cell (Regulatory Cell)

A type of T cell that releases cytokines to activate other immune cells like B cells and other T cells, playing a vital role in coordinating the immune response.

Signup and view all the flashcards

CD8+ T-Cytotoxic Cell (Effector Cell)

A type of T cell that destroys tumor cells and virus-infected cells. They serve as the body's assassins, targeting and eliminating infected or abnormal cells.

Signup and view all the flashcards

Memory Lymphocytes

Long-lived lymphocytes produced during an immune response that remain in the body. They provide a faster, more potent response upon re-encountering the same antigen, ensuring lasting protection without noticeable symptoms.

Signup and view all the flashcards

Major Histocompatibility Complex (MHC)

A complex set of cell surface molecules that help distinguish between normal 'self' cells and foreign invaders. Each person has a unique set of MHC proteins, making it a crucial factor in tissue compatibility for transplants.

Signup and view all the flashcards

MHC Class I

MHC molecules found on the surface of all nucleated cells. They bind to and display peptide fragments of antigens, alerting the immune system when a cell has been infected or cancerous.

Signup and view all the flashcards

MHC Class II

MHC molecules found on the surface of antigen-presenting cells (APCs). They present processed antigen fragments to T-helper cells, leading to their activation and initiation of an immune response.

Signup and view all the flashcards

Study Notes

Immunity Overview

  • Immunity is a defense mechanism
  • Key components include lymphocytes, cytokines, MHCs
  • Two main categories: humoral and cell-mediated immunity

Immune System Components

  • Lymphatic System:

    • Cervical lymph nodes
    • Thymus
    • Right lymphatic duct
    • Cisterna chyli
    • Axillary lymph nodes
    • Spleen
    • Palatine tonsil
    • Thoracic duct
    • Inguinal lymph nodes

  • Immune System (v.s Lymphatic system):

    • Mucous membranes
    • Lymphatic vessels
    • Thymus
    • Lymph Nodes
    • Spleen
    • Lymphatic Vessels

  • Bone Marrow:

    • Component of immune system
    • Involved in forming blood cells

Blood Cells

  • Formed elements:
    • Platelets
    • White blood cells (WBCs) - Leukocytes
    • Red blood cells (RBCs) - Erythrocytes
  • Differential WBC count: 4800-10800/mm^3
  • Granulocytes:
    • Neutrophils (50-70%)
    • Eosinophils (2-4%)
    • Basophils (0.5-1%)
  • Agranulocytes:
    • Lymphocytes (25-45%)
    • Monocytes (3-8%)
  • Mnemonic for WBCs: Never Let Monkeys Eat Bananas (most to least abundant)

Blood Components

  • Cells:
    • Leukocytes (45%)
    • Erythrocytes
  • Plasma (55%):
    • Proteins (albumin, fibrinogen, etc.)
    • Water
    • Other (carbohydrates, lipids, vitamins, enzymes, electrolytes)
  • Cellular components: Functions include phagocytosis (neutrophils), inflammation response, and phagocytosis of pathogens (etc.)

Innate Immunity

  • First Line of Defense:

    • Intact skin and mucous membranes
    • Protective chemicals of the skin and mucous membranes

  • Second Line of Defense:

    • Phagocytes (neutrophils, macrophages, etc.)
    • Natural killer (NK) cells
    • Antimicrobial proteins
    • Inflammation
    • Fever

Physical Barriers

  • Skin:

    • Mechanical barrier to pathogens
    • Keratin provides waterproofing and resistance.
    • Acidity (pH 3-5) inhibits bacterial growth.

  • Mucous Membranes:

    • Traps microorganisms and other particles.
    • Cilia move mucus and debris out of the respiratory tract.
    • Tears, saliva, and urine cleanse surfaces and contain antibacterial enzymes.

  • Second Line of Defense: Phagocytosis - process by which pathogens are engulfed and destroyed.

Inflammation

  • Part of the body's second line of defenses
  • Non-specific response
  • Often due to physical damage, chemical damage, ischemia, allergic reactions, infections, etc.
  • Rapid response
  • Regardless of cause
  • Cardinal signs: heat, redness, swelling, pain, loss of use
  • Series of chemical mediators released (histamine, kinins, prostaglandins)

Systemic Effects of Inflammation

  • May include malaise, fatigue, headache, loss of appetite.
  • Pyrexia (fever): abnormally high body temperature to kill invading organisms or increase metabolic rate.
  • Fever (over 42°C): can be life-threatening as it disrupts mitochondria function and cellular proteins, potentially triggering apoptosis

Fever

  • Occurs when WBCs encounter foreign substances (pyrogens).
  • Pyrogens (interleukins, etc.) circulate and affect hypothalamus.
  • Hypothalamus raises body temperature to fight infection.

Acute vs. Chronic Inflammation

  • Acute: Brief response, resolves quickly (e.g., minor injury) , local effects primary
  • Chronic: Persistent inflammation, long term, caused by persistent irritants. Can lead to tissue damage or disease.

Adaptive Immunity

  • Mechanism helps to clear specific foreign matter
  • Takes longer to mount but more effective.
  • Immune system, central and peripheral lymphoid tissues
  • Major players: T and B lymphocytes, antibodies, macrophages, dendritic cells

Immunity - Antigens

  • Antigens are foreign substances
  • Recognized by receptors on immune cells and antibodies
  • Examples: bacteria, viruses, fungi, pollen, toxins, transplanted organs etc.

Antigen Determinants

  • Small pieces of an antigen recognized by immune cells or antibodies.
  • Single antigen may have multiple epitopes

Immunity - Immune Cells

  • Major players: T and B lymphocytes
  • Other cells: macrophages, dendritic cells
  • Regulatory cells: coordinate immune response, activate other immune cells
  • Effector cells: destroy and clear antigens (eg., cytotoxic T lymphocyte)

Immunity Lymphocytes

  • Produced in bone marrow and educated, self-tolerant

Immunity - Cell-Surface Receptors

  • Activation of lymphocytes when antigens recognize specific receptors
  • B-cells – membrane-bound immunoglobulins (antibodies)
  • T-cells – recognize antigen associated with markers (MHC)

Immunity - MHC Class I

  • Cell-surface glycoproteins interact with antigen receptors on T cytotoxic cells.
  • Informs immune system of cellular infection

Immunity - MHC Class II

  • Interact with CD4 T-helper cells and presenting digested fragments.
  • Helps activate other lymphocytes in the immune response

Immunity - Macrophages

  • Develop from monocytes and migrate to tissues
  • Free: wander tissue spaces
  • Fixed: permanent residents in organs (e.g., Kupffer's cells in liver)
  • Functions include phagocytosis, antigen presentation

Immunity - Dendritic Cells

  • Star-shaped APCs located in lymphoid tissues
  • Capture antigens and migrate to lymph nodes to activate T cells
  • Presenting a digested antigen with MHC class II

Studying That Suits You

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

Quiz Team

Related Documents

Immunity In Class Part 1 W25 (1) PDF

Description

Test your knowledge on the innate immune system and its components. This quiz covers topics such as phagocytosis, lysozyme functions, and the role of skin and mucous membranes in bodily defenses. Dive into the key concepts and mechanisms that protect the body from pathogens.

More Like This

Immune Response Mechanisms
8 questions

Immune Response Mechanisms

ResoundingOrphism avatar
ResoundingOrphism
Nonspecific Innate Immune Mechanisms Quiz
11 questions

Nonspecific Innate Immune Mechanisms Quiz

MotivatedAlexandrite avatar
MotivatedAlexandrite
Innate Immunity Overview
29 questions

Innate Immunity Overview

HottestConflict avatar
HottestConflict
Immunité Innée et Phagocytose
45 questions

Immunité Innée et Phagocytose

LuckiestCitrine887 avatar
LuckiestCitrine887
Use Quizgecko on...
Browser
Open
Browser
Browser