B-Cellular Events Overview
45 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

What are chemical mediators responsible for in the body?

  • Storing nutrients
  • Regulating body temperature
  • Assisting in inflammatory processes (correct)
  • Facilitating oxygen transport

Which of the following is an example of an exogenous chemical mediator?

  • Histamine
  • Leukocytes
  • E. coli (correct)
  • Fibroblasts

Which cell type is primarily responsible for producing endogenous chemical mediators at the site of inflammation?

  • Adipocytes
  • Hepatocytes
  • Endothelial cells (correct)
  • Myocytes

What type of chemical mediators are synthesized by the liver?

<p>Circulating plasma proteins (B)</p> Signup and view all the answers

What is the role of the complement system in inflammation?

<p>To enhance the inflammatory response (D)</p> Signup and view all the answers

Which of the following statements about chemical mediators is correct?

<p>They are responsible for both vascular and cellular events. (B)</p> Signup and view all the answers

The release of exogenous chemical mediators leads to what effect at the venule site?

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

What is the primary function of phagocytotic cells?

<p>To ingest and destroy solid particles (C)</p> Signup and view all the answers

Which type of phagocytic cell is primarily associated with early acute inflammation?

<p>Polymorphonuclear neutrophils (PMNs) (A)</p> Signup and view all the answers

What is Opsonization?

<p>The coating of particles for recognition by phagocytic cells (A)</p> Signup and view all the answers

What role do IgG and C3b play in phagocytosis?

<p>They coat particles for opsonization (A)</p> Signup and view all the answers

Which step in phagocytosis involves the formation of a phagosome?

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

What happens during the degradation and killing step of phagocytosis?

<p>Fusion of phagosomes and lysosomes (B)</p> Signup and view all the answers

Which cells are known as macrophages?

<p>Cells associated with late acute and chronic inflammation (D)</p> Signup and view all the answers

How long are PMNs typically present during inflammation?

<p>1-2 days (C)</p> Signup and view all the answers

What is the role of phagolysosomes?

<p>Degradation and killing of particles (A)</p> Signup and view all the answers

Which of the following correctly describes macrophages?

<p>They can engulf both small and large particles. (D)</p> Signup and view all the answers

What is the primary mechanism of phagocytosis that significantly increases oxygen consumption?

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

Which enzyme is responsible for producing oxygen metabolites during the oxygen-dependent mechanism?

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

Which of the following contributes to the oxygen-independent mechanism?

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

What is the role of myeloperoxidase in phagocytosis?

<p>To oxidize microbial proteins (B)</p> Signup and view all the answers

The low pH within the phagolysosome primarily affects microbial growth how?

<p>Inhibits their replication (B)</p> Signup and view all the answers

Which protein is NOT associated with the oxygen-independent mechanism?

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

During phagocytosis, what is formed when a phagosome fuses with a lysosome?

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

Which of the following is a product of the oxygen-dependent mechanism?

<p>Hydrogen peroxide (Hâ‚‚Oâ‚‚) (B)</p> Signup and view all the answers

What is the primary role of PECAM-1 in leukocyte transmigration?

<p>To mediate adhesion between leukocytes and endothelium (D)</p> Signup and view all the answers

Which process describes the release of digested material from the phagocyte after phagocytosis?

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

Which mechanism of phagocytosis is considered more effective?

<p>Oxygen-dependent mechanism (D)</p> Signup and view all the answers

Which of the following represents a step involved in the process of leukocyte transmigration?

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

What type of factors are primarily responsible for directing leukocyte movement towards an inflammation site?

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

Which of the following is NOT considered an endogenous chemotactic factor?

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

What is the main function of leukotriene B4 (LTB4) in the context of leukocyte behavior?

<p>It acts as a chemotactic agent for leukocytes (B)</p> Signup and view all the answers

What describes the process of margination in leukocyte behavior?

<p>Leukocytes sticking to the vessel wall (A)</p> Signup and view all the answers

Which of the following correctly describes chemotaxis?

<p>Movement of leukocytes towards a chemical gradient (A)</p> Signup and view all the answers

What role do selectins play in leukocyte physiology?

<p>They initiate the rolling process (C)</p> Signup and view all the answers

Which complement component is especially known for its chemotactic properties for leukocytes?

<p>C5a (C)</p> Signup and view all the answers

What is the sequence of steps in leukocyte movement across the endothelium?

<p>Margination, rolling, firm adhesion, transmigration (A)</p> Signup and view all the answers

What physiological change initiates the process of margination during inflammation?

<p>Increased plasma viscosity (C)</p> Signup and view all the answers

Which process follows the margination of leukocytes in the emigration steps?

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

What role do E-selectins play in the rolling phase of leukocyte emigration?

<p>They mediate the rolling movement of leukocytes (A)</p> Signup and view all the answers

What is the final step in the emigration process of leukocytes through the endothelial barrier?

<p>Trans-migration (D)</p> Signup and view all the answers

During inflammation, what effect does stasis have on the flow of leukocytes?

<p>It facilitates leukocyte accumulation at the vessel periphery (A)</p> Signup and view all the answers

What characterizes normal blood flow within blood vessels?

<p>Laminar flow allows plasma to flow alongside leukocytes (A)</p> Signup and view all the answers

What is the primary consequence of increased plasma viscosity during an inflammatory response?

<p>Decreased blood flow (C)</p> Signup and view all the answers

Which of the following best defines diapedesis in leukocyte emigration?

<p>The movement of leukocytes into adjacent tissues (A)</p> Signup and view all the answers

Flashcards

Margination

Leukocytes accumulating along blood vessel endothelium during inflammation.

Rolling leukocytes

Leukocytes loosely attach to endothelium, following margination, before adhesion, mediated by E-selectins.

Adhesion

Leukocytes firmly attaching to endothelial cells.

Diapedesis

Leukocytes migrating across the endothelium into tissue.

Signup and view all the flashcards

E-selectins

Molecules on endothelium that mediate leukocyte rolling.

Signup and view all the flashcards

Inflammation

The body's response to an injury or infection characterized by a series of steps to destroy the injurious agent.

Signup and view all the flashcards

Laminar flow

Normal blood flow in vessels, with cells in the center and plasma at edges.

Signup and view all the flashcards

Leukocytes

White blood cells that fight infection and injury.

Signup and view all the flashcards

Leukocyte Transmigration

Movement of leukocytes across the endothelium of blood vessels.

Signup and view all the flashcards

Chemotaxis

Leukocyte movement towards an inflammatory site along a chemical gradient.

Signup and view all the flashcards

Chemotactic Agent (Exogenous)

Chemical signal from outside the body (e.g., bacteria products, toxins).

Signup and view all the flashcards

Chemotactic Agent (Endogenous)

Chemical signal from within the body (e.g., cytokines, complement).

Signup and view all the flashcards

Cytokines (Chemokines)

Endogenous proteins triggering chemotaxis, a type of signaling molecule.

Signup and view all the flashcards

PECAM-1

Protein allowing leukocytes to cross the endothelium.

Signup and view all the flashcards

Leukotriene B4 (LTB4)

Endogenous chemical signaling molecule involved in chemotaxis.

Signup and view all the flashcards

Complement C5a

Complement component that is a chemotactic agent.

Signup and view all the flashcards

Diapedesis

Leukocyte migration across the endothelium into the tissues.

Signup and view all the flashcards

Inflammatory Site

Location within the tissue with an immune response.

Signup and view all the flashcards

Phagocytosis Definition

Ingestion and destruction of solid particles by phagocytic cells, like neutrophils and macrophages.

Signup and view all the flashcards

Phagocytic Cells Type 1

Polymorphonuclear neutrophils (PMNs), also called microphages, involved in early acute inflammation.

Signup and view all the flashcards

Phagocytic Cells Type 2

Macrophages, involved in late acute and chronic inflammation, good at both big and small particles.

Signup and view all the flashcards

Opsonization

Coating particles to make them easier for phagocytes to recognize & attach. Important for engulfment.

Signup and view all the flashcards

Opsonins (IgG & C3b)

Molecules (IgG & C3b) that coat particles to prepare them for phagocytosis.

Signup and view all the flashcards

Phagosome Formation

Engulfment of a particle by phagocyte extensions, creating a membrane-bound vesicle.

Signup and view all the flashcards

Phagolysosome

Fusion of phagosome with lysosome, leading to particle degradation & killing.

Signup and view all the flashcards

Phagocytosis Step 1

Recognition and attachment of particles to phagocytic cells mediated by opsonins.

Signup and view all the flashcards

Phagocytosis Step 2

Engulfment of the bound particle by the phagocytic cell, creating an enclosed vesicle called phagosome.

Signup and view all the flashcards

Phagocytosis Step 3

The degradation and destruction of the enclosed particle by the fusion of the phagosome and lysosome creating an area called phagolysosome.

Signup and view all the flashcards

Chemical Mediators

Substances that help inflammatory processes, acting on blood vessels, inflammatory cells, or other cells, causing vascular and cellular events.

Signup and view all the flashcards

Exogenous Mediators

Chemical mediators originating from outside the body (e.g., bacteria or toxins).

Signup and view all the flashcards

Endogenous Mediators

Chemical mediators produced within the body, at the site of inflammation, by cells.

Signup and view all the flashcards

Cell-Derived Mediators

Chemical mediators made by cells (leukocytes, endothelial cells, fibroblasts) at the site of inflammation.

Signup and view all the flashcards

Circulating Plasma Proteins

Inactive proteins produced by the liver, part of the inflammatory response, which become active later.

Signup and view all the flashcards

Vascular Phenomena

Changes in blood vessels during inflammation, caused by mediators.

Signup and view all the flashcards

Inflammatory Response

The body's reaction to injury or infection characterized by a series of events to eliminate the harmful agent.

Signup and view all the flashcards

Phagocytosis

The process where a cell engulfs and digests foreign material.

Signup and view all the flashcards

Oxygen-dependent Mechanism

The main phagocytosis method, creating reactive oxygen species to kill microbes.

Signup and view all the flashcards

Phagolysosome

Structure formed by combining a phagosome and lysosome for digestion.

Signup and view all the flashcards

NADPH oxidase

Enzyme producing oxygen metabolites (important for killing pathogens).

Signup and view all the flashcards

Oxygen metabolites

Reactive chemicals within phagosomes, killing microbes.

Signup and view all the flashcards

Myeloperoxidase

Enzyme oxidizing microbial proteins to disrupt their membranes.

Signup and view all the flashcards

Oxygen-independent Mechanism

Less effective phagocytosis method using enzymes like lysozyme.

Signup and view all the flashcards

Lysozyme

Enzyme breaking down bacterial cell walls.

Signup and view all the flashcards

Phagosome

Membrane-bound vesicle containing engulfed material.

Signup and view all the flashcards

Lysosome

Cell compartment containing digestive enzymes.

Signup and view all the flashcards

Study Notes

B-Cellular Events

  • A group of sequential processes results in formation of cellular exudation & destroy the injurious agent.
  • Normal blood flow in lumen of blood vessels, the cellular elements → flow in the center of the vessel → laminar flow, plasma is flowing adjacent to endothelium, with stasis during inflammation Leukocytes accumulate at the periphery of vessel along the endothelium (process called Margination)

I. Emigration of Leukocytes

  • Divided into 4 steps
    • 1. Margination: Increased plasma viscosity due to loss of intravascular fluid → Decreased blood flow → White blood cells fall out of axial stream into plasmatic zone
    • 2. Rolling: Is mediated by the action of E-selectins which bind endothelial cells loosely to leukocytes producing a characteristic rolling movement of leukocytes along the endothelial surface.
    • 3. Adhesion: Leukocytes adhere to the endothelial surface through the
    • 4. Diapedesis (trans-migration across the endothelium):

Studying That Suits You

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

Quiz Team

Description

This quiz covers the key processes involved in the emigration of leukocytes during inflammation, including margination, rolling, adhesion, and diapedesis. Understand the significance of each step and their roles in cellular exudation as the body responds to injury.

More Like This

Leukocyte Migration Quiz
14 questions

Leukocyte Migration Quiz

StupendousNovaculite avatar
StupendousNovaculite
Leukocyte Migration and Trafficking
24 questions

Leukocyte Migration and Trafficking

TopQualityWhite avatar
TopQualityWhite
Biología: Reclutamiento de leucocitos en inflamación
10 questions

Biología: Reclutamiento de leucocitos en inflamación

StrongerCalcium avatar
StrongerCalcium
Inflamasi Akut
31 questions

Inflamasi Akut

EasierUnakite2043 avatar
EasierUnakite2043
Use Quizgecko on...
Browser
Open
Browser
Browser