Concept of Immunity

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary function of T cells in the immune system?

To sense foreign substances
To destroy antigens and infected cells (correct)
To neutralize toxins
To produce antibodies

What is the role of B lymphocytes in the immune system?

To produce antibodies (correct)
To sense foreign substances
To destroy infected cells
To activate complement proteins

What is the result of immunisation?

The body produces more T cells
The body becomes immune to only bacterial infections
The body becomes immune to all diseases
The body produces antibodies that protect against future infections (correct)

What is the function of antibodies in the immune system?

To lock onto specific antigens (D) Signup and view all the answers

What type of immunity is present from birth?

Innate immunity (C) Signup and view all the answers

What is the term for the protection offered by the immune system?

Immunity (A) Signup and view all the answers

What is the primary function of the immune system?

To recognize and remove foreign material from the body (D) Signup and view all the answers

What is the primary function of neutrophils in the immune system?

To consume bacteria (B) Signup and view all the answers

What is the purpose of lysozyme in tears and saliva?

To breakdown foreign material (C) Signup and view all the answers

What happens if the first line of defense is breached?

The body releases antibodies against pathogens (C) Signup and view all the answers

What is the role of B lymphocytes in the immune system?

To produce antibodies specific to foreign particles (B) Signup and view all the answers

What is the purpose of mucus in the respiratory and alimentary tracts?

To trap microbes (A) Signup and view all the answers

Where do T cells mature in the body?

Thymus gland (C) Signup and view all the answers

What is the characteristic of intact skin that makes it difficult to penetrate?

It is impermeable and waterproof (A) Signup and view all the answers

What is the function of cytotoxic T-cells?

To kill cancer cells (A) Signup and view all the answers

What is the outcome of the body's ability to respond to pathogens?

The foreign material is removed quickly and effectively (A) Signup and view all the answers

When do T-cells first appear in the fetal development?

12 weeks postconception (A) Signup and view all the answers

What is the role of helper T-cells in the immune system?

To release cytokines to initiate immune responses (C) Signup and view all the answers

What is the primary function of phagocytes in the immune system?

To chew up invading organisms (D) Signup and view all the answers

When do B lymphocytes first appear in the fetal development?

8 weeks postconception (D) Signup and view all the answers

What is the function of regulatory T-cells?

To regulate immune reactions (B) Signup and view all the answers

What is the primary function of the skin in relation to the immune system?

To act as a barrier to block germs from entering the body (D) Signup and view all the answers

What type of immunity develops over time as we are exposed to diseases or immunized against them?

Adaptive immunity (B) Signup and view all the answers

What is the term for the development of immune defense mechanisms in the body?

Development of immunity (A) Signup and view all the answers

What is the primary source of temporary immunity for a newborn baby?

Antibodies in the mother's breast milk (B) Signup and view all the answers

What is an example of an immune disorder that is present at birth?

Severe combined immunodeficiency (SCID) (B) Signup and view all the answers

What can weaken the immune system for a brief time?

Infections like the flu virus (C) Signup and view all the answers

What is the result of HIV infection on the immune system?

It destroys important white blood cells and weakens the immune system (A) Signup and view all the answers

Flashcards are hidden until you start studying

Study Notes

Immunity and the Immune System

Immunity is the body's ability to recognize foreign material, respond to it, and remove it quickly and effectively.
The immune system is a part of the body's protective and defensive mechanism against pathogenic microorganisms.

Types of Immunity

Innate immunity: a type of general protection that everyone is born with, providing immediate defense against infection.
Adaptive immunity: develops throughout life, providing long-term protection against specific pathogens through immunization or infection.
Passive immunity: "borrowed" from another source, lasting for a short time, such as antibodies in a mother's breast milk.

The Immune System's Components

White blood cells (leukocytes): play an important role in the immune system.
Phagocytes: a type of white blood cell that engulfs and digests foreign particles and microorganisms.
Neutrophils: a type of phagocyte that consumes bacteria.
Lymphocytes: B cells and T cells, produced in the bone marrow and mature in the bone marrow and thymus gland, respectively.
B cells (humoral immunity): produce antibodies specific to foreign particles or antigens.
T cells (cellular immunity): differentiate into helper cells, cytotoxic cells, and regulatory cells.

Development of Immunity

The development of immune defense mechanisms begins early in fetal life but is not yet completed at birth.
T-cells are first detectable at 12 weeks and acquire functional capabilities at 16 weeks.
B-cells can be identified in the fetal liver at eight weeks and are functional at 12-13 weeks.

Immune Disorders

Severe combined immunodeficiency (SCID): a genetic disorder present at birth, characterized by the absence of important white blood cells.
Temporary acquired immune deficiencies: can be caused by certain medicines, infections, smoking, alcohol, and poor nutrition.
AIDS: an acquired viral infection that destroys important white blood cells and weakens the immune system.