Biology Immune System Flashcards

Questions and Answers

Identify three types of barriers in the body's first line of defense. Give an example of each type of barrier.

Mechanical - mucus, 2. Chemical - Low pH, 3. Biological - bacteria on human skin.

What is the body's second line of defense? When does it take effect?

The body's second line of defense includes the inflammatory response and phagocytosis by nonspecific leukocytes, taking effect after the first part fails.

Identify the roles of nonspecific leukocytes in the body's second line of defense.

Nonspecific leukocytes fight infections and remove debris.

State how phagocytosis helps defend the body from pathogens.

Phagocytes eat up pathogens. Signup and view all the answers

What is nonspecific defense?

Nonspecific defense is the response of leukocytes that is the same regardless of the type of pathogen involved. An example is phagocytosis. Signup and view all the answers

List three parts of the lymphatic system and their functions.

<ol> <li>Organs: bone marrow, produces lymphocytes; 2. Lymph vessels: circulate lymph; 3. Lymph nodes: filter out small structures.</li> </ol> Signup and view all the answers

What are antigens, and how do lymphocytes 'recognize' them?

Antigens are molecules recognized as foreign by the immune system. Lymphocytes recognize them through receptor molecules that bind to specific antigens. Signup and view all the answers

How do plasma cells form, and how do they help fight pathogens?

B cells are activated by antigens, attracting a helper T-cell that instructs the B cell to develop into a plasma cell. Signup and view all the answers

Describe one way that cytotoxic T cells destroy cells infected with viruses.

The T cell releases proteins that form pores in the membrane of the infected cell. Signup and view all the answers

What is immunity? What role do memory cells play in immunity?

Immunity is the ability to resist a pathogen. Memory cells are long-living plasma cells that remember the shape and form of viruses. Signup and view all the answers

What's the difference between an autoimmune disorder and an immunodeficiency disorder?

Immunodeficiency occurs when the immune system cannot fight off pathogens, while autoimmune diseases arise when the immune system mistakenly attacks the body's own molecules. Signup and view all the answers

Study Notes

First Line of Defense

Three types of barriers protect the body:
- Mechanical barriers such as mucus
- Chemical barriers like low pH environments
- Biological barriers, exemplified by beneficial bacteria on skin

Second Line of Defense

Involves the inflammatory response and phagocytosis by nonspecific leukocytes
Activated when the first line of defense fails
Chemical signals are released when tissues are damaged, prompting responses

Nonspecific Leukocytes

Their primary role includes combating infections and clearing away cellular debris
Not specialized against specific pathogens

Phagocytosis

Process where phagocytes ingest and eliminate pathogens
Essential for ongoing immune defense

Nonspecific Defense

Characterized by a universal response from leukocytes regardless of the pathogen type
Phagocytosis serves as a prime example of this response

Lymphatic System Components

Comprises organs, lymph vessels, and lymph nodes:
- Bone marrow is a key organ producing lymphocytes
- Lymph vessels circulate lymph fluid containing immune cells
- Lymph nodes act as filters, removing small pathogens and debris

Antigens and Lymphocyte Recognition

Antigens are foreign molecules that trigger immune responses
Lymphocytes recognize these antigens through specific receptor molecules on their surfaces

Plasma Cells and Pathogen Response

Formed when B cells are activated by the binding of antigens and helper T cell stimulation
Plasma cells produce antibodies to target and neutralize pathogens

Cytotoxic T Cells

Destroy virus-infected cells by releasing proteins that create pores in the target cell’s membrane
This mechanism promotes cell death in infected cells

Immunity and Memory Cells

Immunity refers to the body's capability to resist pathogens
Memory cells, derived from long-lived plasma cells, retain information about specific pathogens for quicker responses upon re-exposure

Autoimmune vs. Immunodeficiency Disorders

Autoimmune disorders occur when the immune system mistakenly attacks its own cells, viewing them as threats
Immunodeficiency disorders arise when the immune system fails to function adequately, leading to heightened susceptibility to infections

Description

Test your knowledge on the immune system through a set of flashcards focused on the body's defenses. This quiz covers key concepts such as barriers, inflammatory responses, and leukocytes. Ideal for biology students or anyone looking to understand how our immune system functions.