Ultimate Quiz On Immunity Test

Mucus production is not a sign of inflammation. Inflammation is a response of the body's immune system to injury or infection, characterized by redness, pain, heat, and swelling. Mucus production, on the other hand, is a normal bodily function that helps to protect and lubricate the respiratory and digestive systems. While increased mucus production can occur during certain infections or allergies, it is not directly associated with inflammation.

Natural killer cells are a type of white blood cell that play a crucial role in the immune system's defense against infectious microbes and tumor cells. They are able to recognize and kill abnormal cells in the body, including virus-infected cells and cancer cells, without the need for prior activation. Natural killer cells release toxic substances called perforins, which create pores in the target cell's membrane, leading to cell death. Therefore, natural killer cells are an important component of the body's innate immune response against pathogens and abnormal cells.

Susceptibility refers to a lack of resistance or vulnerability to a particular disease or infection. It implies that an individual is more likely to contract the disease or be affected by it due to a weakened immune system or other factors. This term is commonly used in the context of public health and epidemiology to describe the susceptibility of a population or group to a specific disease.

The thymus produces the hormone that promotes maturation of T cells. T cells are a type of white blood cell that plays a crucial role in the immune response. The thymus is a specialized organ located in the chest, near the heart, and it is responsible for the development and maturation of T cells. The hormone produced by the thymus, called thymosin, helps in the maturation process of T cells, allowing them to become fully functional and capable of recognizing and fighting off pathogens.

An acute allergic response can lead to anaphylactic shock, which is a severe and potentially life-threatening allergic reaction. Anaphylactic shock occurs when the immune system overreacts to an allergen, such as certain foods, medications, or insect stings. This overreaction causes the release of large amounts of histamine and other chemicals, leading to a sudden drop in blood pressure, difficulty breathing, and other symptoms. Without prompt medical treatment, anaphylactic shock can be fatal.

The pancreas is not considered an organ of the immune system because its primary function is to produce digestive enzymes and regulate blood sugar levels, rather than directly participating in immune responses. The spleen, lymph nodes, red bone marrow, and thymus are all organs that play important roles in the immune system by producing and maturing immune cells, filtering out pathogens, and coordinating immune responses.

Immunodeficiency diseases refer to a group of disorders where the immune system is unable to effectively defend the body against pathogens. This can result in recurrent infections, as the immune system is weakened and unable to mount a proper response. Unlike allergies, which are an overreaction of the immune system to harmless substances, immunodeficiency diseases involve a compromised immune system. Autoimmune diseases, on the other hand, occur when the immune system mistakenly attacks the body's own cells and tissues. Transplantations involve the transfer of organs or tissues from one person to another, which is not directly related to the inability of the immune system to protect against pathogens.

The skeletal muscle and respiratory pumps are used in the lymphatic, immune, and cardiovascular systems. The skeletal muscles help to contract and squeeze the lymphatic vessels, assisting in the movement of lymph fluid throughout the body. This helps to remove waste products, toxins, and pathogens from tissues, and also aids in the transportation of immune cells. The respiratory pumps, which involve the movement of the diaphragm and rib muscles during breathing, help to create pressure changes in the thoracic cavity. This facilitates the flow of both lymph and blood through the cardiovascular system, ensuring efficient oxygenation and nutrient delivery to tissues.

The spleen is responsible for removing worn out blood cells from the body. It filters the blood and identifies and removes old or damaged red blood cells, helping to maintain the overall health and functionality of the blood.

An antigen is a foreign substance that enters the body and triggers an immune response. When an antigen enters the body, it stimulates the production of specific antibodies by the immune system. These antibodies are produced by B cells and are designed to recognize and bind to the antigen, marking it for destruction by other immune cells. Therefore, the presence of an antigen induces the production of a specific antibody to combat the foreign substance.

Nonspecific immunity, also known as innate immunity, is the type of immunity that defends against any type of invader. It is the first line of defense and includes physical barriers such as the skin, as well as cellular and chemical components that work to eliminate pathogens. This type of immunity is not specific to any particular invader and provides a general defense mechanism against a wide range of pathogens.

Lymphocytes are a type of white blood cell that plays a crucial role in the immune system. They are responsible for recognizing and attacking foreign cells, such as bacteria, viruses, and other pathogens, in order to protect the body from infection and disease. Lymphocytes have receptors on their surface that allow them to identify and bind to specific molecules on the surface of foreign cells, triggering an immune response. This recognition and response to foreign cells is essential for the body's defense against pathogens.

Opsonization is the process by which pathogens or other foreign particles are marked for destruction by immune cells. This process involves the coating of the pathogen with opsonins, such as antibodies or complement proteins, which enhances the recognition and engulfment of the pathogen by phagocytic cells. By coating the pathogen, opsonization makes it more susceptible to phagocytosis, leading to its destruction.

Helper T cells, also known as CD4+ T cells, display CD4 on their membrane and are associated with MHC class II molecules. They play a crucial role in the immune response by activating other immune cells, such as B cells and cytotoxic T cells, through the release of cytokines. Helper T cells are important for coordinating and regulating the immune response, making them an essential component of the adaptive immune system.

Macrophages are immune cells that play a crucial role in the body's defense against pathogens. They are responsible for engulfing and destroying foreign substances, including bacteria and viruses. Unlike the other options listed, macrophages do not provide a physical or chemical barrier. Instead, they actively participate in the immune response by identifying and eliminating pathogens. Therefore, macrophages are the correct answer as they do not function as a physical or chemical barrier.

Complement proteins are a group of proteins that play a crucial role in the immune response. They enhance the immune system's ability to fight off infections by promoting cytolysis (the destruction of cells), phagocytosis (the engulfment and digestion of pathogens by immune cells), and inflammation (a response that helps recruit immune cells to the site of infection). Therefore, complement proteins are able to effectively eliminate pathogens and protect the body from infections.

When B and T cells are fully developed and mature, they are considered to be immunocompetent. This means that they have acquired the ability to recognize and respond to specific antigens, thus playing a crucial role in the immune response against pathogens. Immunocompetent cells are capable of producing specific antibodies (B cells) or directly killing infected cells (T cells), thereby contributing to the overall immune defense of the body.

The lymphatic and immune system is responsible for several functions in the body, including draining excess interstitial fluid, transporting dietary lipids, and carrying out immune responses. However, maintaining water homeostasis in the body is not one of its functions. Water homeostasis is primarily regulated by the kidneys through processes such as filtration, reabsorption, and excretion. The lymphatic and immune system plays a crucial role in defending the body against pathogens and maintaining fluid balance, but it does not directly regulate water homeostasis.

Interferons are anti-viral substances produced by infected cells in response to viral infection. They have the ability to diffuse to uninfected cells and inhibit viral replication by reducing the production of viral proteins. This helps to limit the spread of the virus to other cells and control the infection. Therefore, interferons are the correct answer as they specifically target viral proteins and have a broad antiviral activity.

IgA antibodies are mainly found in sweat, tears, breast milk, and GI secretions. These antibodies play a crucial role in protecting the mucosal surfaces of the body, such as the respiratory and gastrointestinal tracts, from pathogens. They help prevent the attachment and invasion of bacteria and viruses, neutralize toxins, and promote the elimination of pathogens through the mucosal secretions. IgA antibodies are particularly important for the defense against infections in the mucosal areas, making them the correct answer in this case.

Active immunity refers to the immune response that occurs when the body is exposed to a pathogen naturally, such as through infection or exposure to the pathogen in the environment. This exposure triggers the production of antibodies and memory cells, which provide long-lasting protection against future infections from the same pathogen. Therefore, the correct answer is active immunity. Passive immunity, on the other hand, refers to the temporary immunity that is acquired from another source, such as through the transfer of antibodies from a mother to her baby during pregnancy.

The correct answer is "Antigen presenting cells". These cells, including macrophages, B cells, and dendritic cells, play a crucial role in the immune response by presenting antigens to T cells. This presentation allows T cells to recognize and respond to foreign substances, such as pathogens or cancer cells. Antigen presenting cells are essential for initiating and coordinating immune responses.

Cytokines are small hormone-like proteins that can either stimulate or inhibit various cell functions. They play a crucial role in cell signaling and immune responses. They are involved in regulating inflammation, immune cell development, and communication between cells. Cytokines can be produced by various cell types, including immune cells, and they act as messengers to coordinate the body's response to infection, injury, or disease. Therefore, cytokines are the correct answer as they fit the description of being small hormones that can stimulate or inhibit cell functions.

The major difference between lymph and interstitial fluid is their location. Lymph is found within the lymphatic vessels and lymph nodes, while interstitial fluid is found in the spaces between cells and tissues.

Lipids cause lymph from the small intestines to appear white. This is because lipids are insoluble in water and are transported in the lymphatic system in the form of chylomicrons. Chylomicrons are large lipid droplets that give the lymph a milky appearance, making it appear white.

Macrophages provide a non-specific cellular disease resistance mechanism. Macrophages are a type of white blood cell that play a crucial role in the immune system's response to infection. They engulf and destroy pathogens, foreign substances, and dead cells through a process called phagocytosis. Unlike T lymphocytes and B lymphocytes, which are specific immune cells that target specific pathogens, macrophages act as the first line of defense against a wide range of pathogens and provide a general defense mechanism against diseases. Memory B cells, on the other hand, are specific immune cells that provide long-term immunity to previously encountered pathogens. Stratified squamous epithelium is a type of tissue that acts as a physical barrier against pathogens but does not provide a cellular disease resistance mechanism.

The left subclavian vein receives lymph from the thoracic duct. The thoracic duct is the largest lymphatic vessel in the body and it drains lymph from the lower body, left upper body, and left side of the head and neck. It then empties into the left subclavian vein, where the lymph is returned to the bloodstream.

Lymphocytes are considered the body's second major defense because they play a crucial role in the immune system. These white blood cells are responsible for recognizing and attacking foreign substances, such as bacteria and viruses, in the body. They are also involved in the production of antibodies, which help to neutralize harmful pathogens. Lymphocytes are a key component of the adaptive immune response, which provides long-term protection against specific pathogens. Therefore, they are an important defense mechanism in the body's immune system.

Fever is the correct answer because it is known to intensify the effect of interferons and promote the rate of repair. When the body experiences an infection or inflammation, it raises its temperature to create an environment that is less favorable for the growth and reproduction of pathogens. This elevated temperature stimulates the production and activity of interferons, which are proteins that help to inhibit viral replication and enhance the immune response. Additionally, fever increases the metabolic rate, which can accelerate tissue repair and healing processes.

The major histocompatibility complex (MHC) and antigen receptors are responsible for diversity in the immune system. The MHC molecules present antigens to T cells, allowing them to recognize and respond to a wide range of pathogens. Antigen receptors, such as the B cell receptor and T cell receptor, are highly diverse and can recognize specific antigens. Together, the MHC and antigen receptors contribute to the diversity of the immune system by allowing it to recognize and respond to a wide variety of pathogens and antigens.

The correct answer is "Tips of the molecules." B cell receptors have variable regions located at the tips of their molecules. These variable regions are responsible for binding to specific antigens, allowing B cells to recognize and respond to different pathogens. The variable regions contain a diverse repertoire of antigen-binding sites, which enables B cells to produce a wide range of antibodies with different specificities. The transmembrane region is responsible for anchoring the receptor to the cell membrane, and there are also constant regions in B cell receptors that provide structural stability.

Perforin does not induce vasodilation and permeability to an infection site. Perforin is a protein that is released by cytotoxic T cells and natural killer cells to create pores in the cell membrane of target cells, leading to their destruction. It is not involved in the process of increasing fluid flow and promoting inflammation at an infection site.

The correct answer is Classical and Alternative complement systems. The given explanation suggests that the activation of both the classical and alternative complement systems will lead to inflammation, enhancement of phagocytosis, and bursting of microbes. These complement systems are part of the immune response and work together to eliminate pathogens and enhance immune defense.

IgM antibodies are produced after an initial exposure to antigens.

A hapten is a small molecule that can bind to an antibody but cannot stimulate an immune response on its own. However, when a hapten is attached to a large carrier molecule, it can elicit an immune response. This is because the immune system recognizes the hapten-carrier complex as foreign and mounts a response against it. Therefore, a hapten can only stimulate an immune response if it is attached to a large carrier molecule.

Hasall's corpuscles are speculated to be the site where T cells die in the thymus. These corpuscles are clusters of epithelial cells found in the medulla of the thymus. They are thought to play a role in the removal of dying T cells and the regulation of their development. Therefore, it is believed that T cells undergo cell death within Hasall's corpuscles in the thymus.

An anergy cell refers to a self-responsive cell that is inactive. It is a cell that should normally respond to a specific antigen, but fails to do so due to a state of immune tolerance or unresponsiveness. This can occur when the cell encounters the antigen repeatedly without appropriate co-stimulation, leading to a lack of immune response. Anergy cells are characterized by their inability to produce an immune response, making them different from other cell types listed in the options.

The thoracic duct is the largest lymphatic vessel in the body and is responsible for draining lymph from the lower limbs, abdomen, left side of the thorax, left upper limb, and left side of the head and neck. Therefore, it makes sense that the lymph from the right foot would empty into the thoracic duct, as it is responsible for draining lymph from the left side of the body.

Lymphotoxin is secreted by T cells and is known to have the ability to fragment DNA. It is a cytotoxic protein that plays a role in immune responses, particularly in the destruction of target cells. Lymphotoxin is a potent mediator of inflammation and can induce cell death in certain types of cells. Therefore, it is the most suitable option among the given choices for a toxin secreted by T cells that is used to fragment DNA.

The primary response will peak 10-17 days after an exposure. This means that the body's immune response to the exposure will reach its highest level during this time period. It is important to note that this is a general timeframe and can vary depending on the specific infection or disease.

B cells are a type of white blood cell that play a crucial role in the immune response. They are responsible for producing antibodies, which are proteins that can recognize and bind to specific foreign antigens. In order for a B cell to become activated and start producing antibodies, it needs to bind to a foreign antigen and receive a co-stimulatory signal. This co-stimulatory signal is usually provided by T cells, which interact with the B cell and help activate it. Therefore, the given statement accurately describes the activation process of B cells.

The inner cortex of the lymph node does not contain any lymphatic nodules. Lymphatic nodules are small, rounded structures that contain lymphocytes and are responsible for filtering and trapping foreign substances in the lymph. The inner cortex, on the other hand, is mainly composed of lymphocytes and reticular fibers. It functions as a site for the proliferation and maturation of lymphocytes. Therefore, it does not contain any lymphatic nodules.

MHC (Major Histocompatibility Complex) is the most polymorphic molecule in the immune system. It plays a crucial role in presenting antigens to T cells, which helps in initiating an immune response. MHC molecules are highly diverse and vary among individuals, allowing the immune system to recognize a wide range of antigens. This polymorphism is important for the immune system to effectively respond to various pathogens and adapt to different environmental challenges.

Reactivity refers to the ability of an antigen to specifically react with the antibodies or cells it has provoked. It indicates the antigen's ability to elicit a response from the immune system. This term describes the specific interaction between antigens and the immune system, highlighting the antigen's capacity to provoke a targeted immune response.