Biology Chapter 21: The Immune System

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary function of the thymus?

Mature T cells (correct)

Produces antibodies

Stores blood

Filters lymph

Natural killer cells are part of adaptive immunity.

False

What are the two types of immunity recognized in the immune system?

Nonspecific (innate) and specific (adaptive) immunity

The __________ produce antibodies in response to antigens.

plasma cells Signup and view all the answers

Which type of phagocyte is the first responder to sites of infection?

Neutrophils Signup and view all the answers

Match the following immune cells with their primary role:

B cells = Produce antibodies T cells = Cell-mediated immunity Macrophages = Phagocytosis Natural Killer Cells = Destruction of infected cells Signup and view all the answers

Memory B cells are involved in the primary immune response.

False Signup and view all the answers

What are the two main types of lymphatic organs?

Primary lymphatic organs and secondary lymphatic organs Signup and view all the answers

The __________ response is characterized by increased body temperature as a defense mechanism.

fever Signup and view all the answers

Which of the following best describes the primary function of the lymphatic system?

Defending against infection and disease Signup and view all the answers

Lymphatic vessels have valves to prevent backflow of lymph.

True Signup and view all the answers

What are the primary lymphatic organs?

Red bone marrow and thymus Signup and view all the answers

The ______ is a secondary lymphatic organ that filters blood and helps in immune response.

spleen Signup and view all the answers

Match the following immune cells with their primary roles:

Neutrophils = Phagocytosis of pathogens B cells = Antibody production Cytotoxic T cells = Killing infected cells Helper T cells = Activating other immune cells Signup and view all the answers

Which of the following is NOT a component of the innate immune response?

Antigen-presenting cells Signup and view all the answers

Memory T cells are responsible for immediate responses to previously encountered antigens.

True Signup and view all the answers

What are the five classes of antibodies?

IgA, IgD, IgE, IgG, IgM Signup and view all the answers

The thoracic duct drains lymph from the ______ side of the body.

left Signup and view all the answers

Which of the following cells is primarily responsible for humoral immunity?

B cells Signup and view all the answers

Study Notes

Lymphatic System Overview

Lymphatic Cells:
- MALT includes Peyer's patches, tonsils, and appendix; essential for monitoring pathogens.
Lymphatic Organs:
- Primary: Red bone marrow (site of B cell maturation), thymus (site of T cell maturation).
- Secondary: Lymph nodes (filter lymph, activate immune response), spleen (filters blood, stores lymphocytes).

Functions of Immune System Cells

Neutrophils: First responders to infection, primarily phagocytic.
Monocytes: Differentiate into macrophages and dendritic cells that present antigens.
Macrophages: Phagocytosis and antigen presentation, crucial for activating T cells.
Eosinophils: Attack parasites and participate in allergic responses.
Natural Killer Cells: Identify and destroy infected or cancerous cells.
Basophils & Mast Cells: Release histamine during inflammation and allergic reactions.
B Cells: Develop into plasma cells that produce antibodies; also form memory B cells.
Plasma Cells: Produce large quantities of antibodies.
Cytotoxic T Cells: Target and destroy infected or abnormal cells.
Helper T Cells: Assist in the activation and functioning of B cells and other T cells.
Memory T Cells: Provide long-term immunity by remembering past infections.
Antigen-Presenting Cells: Present antigens to activate T cells, can be macrophages or dendritic cells.

Nonspecific Defenses (Innate Immunity)

Physical Barriers: Skin and mucous membranes prevent pathogen entry.
Phagocytes: Engage in phagocytosis to eliminate pathogens.
Non-Phagocytes: Includes cells like NK cells that destroy cells without engulfing.
Antimicrobial Proteins: Proteins that inhibit microbial growth, e.g., interferons and complement proteins.
Inflammatory Response: Localized response to injury/infection, characterized by redness, heat, swelling, and pain.
Fever: Elevated body temperature that enhances immune response.

Specific Defenses (Adaptive Immunity)

Cell-Mediated Immunity: T cells specifically target and destroy infected cells, cancerous cells, and regulate immune responses.
T Cell Development: Involves recognition of antigens via specific receptors; include Class I (on all nucleated cells) and Class II MHC (on professional APCs).
Activation of T Cells: Recognized by corresponding antigen, leading to proliferation and differentiation into various functional T cells.
Roles of T Cells:
- CD8 Cytotoxic T Cells: Directly attack infected or cancerous cells.
- CD4 Helper T Cells: Facilitate B cell and other T cell activation through signaling.
Humoral Immunity: B cells target pathogens in bodily fluids, crucial for antibody production.
Antibodies (Immunoglobulins): Five classes (IgG, IgA, IgM, IgE, IgD) with distinct roles and mechanisms of action against pathogens.
B Cell Development: Occurs in bone marrow, leading to the formation of antigen receptors; includes activation process involving clonal expansion and differentiation into plasma cells and memory B cells.
Responses:
- Primary Response: Initial antibody production upon first exposure to an antigen.
- Secondary Response: Faster, stronger response upon re-exposure due to memory B cells.
Passive vs. Active Humoral Immunity:
- Active: Body creates antibodies through response to infection or vaccination.
- Passive: Antibodies acquired from another source, e.g., mother to infant.

Studying That Suits You

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

Description

This quiz focuses on Chapter 21 of biology, which covers the immune system and lymphatic system cells and organs. Test your knowledge on the functions of lymphatic cells, including MALT and various lymphatic organs, as well as the roles of immune system cells like neutrophils and macrophages.