Immune System Chapter 21

Redness, heat, swelling, and pain are classic signs of inflammation. Inflammation is a natural response of the body to injury or infection. It is characterized by increased blood flow to the affected area, resulting in redness and heat. Swelling occurs due to the accumulation of fluid and immune cells. Pain is caused by the release of chemicals that sensitize nerve endings. These symptoms are not specific to hypersensitivity reactions, anaphylaxis, or autoimmune diseases, making inflammation the most appropriate answer.

When the bee venom allergen binds to antibodies on mast cells, it triggers a reaction known as degranulation. This leads to the release of histamine, a substance that plays a crucial role in allergic reactions. Histamine causes blood vessels to dilate, leading to increased blood flow, and also increases the permeability of blood vessels, allowing immune cells to reach the affected area. It is responsible for many of the symptoms associated with allergies, such as itching, swelling, and inflammation. Therefore, the correct answer is histamine.

B and T cells are lymphocytes. Lymphocytes are a type of white blood cell that play a crucial role in the immune system. B cells are responsible for producing antibodies, while T cells are involved in cell-mediated immunity. Both B and T cells are derived from stem cells in the bone marrow and are important in defending the body against infections and diseases.

T cells are classified as killer, helper, suppressor, and memory cells. Killer T cells are responsible for eliminating infected cells, helper T cells assist in activating other immune cells, suppressor T cells regulate the immune response, and memory T cells remember past infections and provide long-term immunity.

A severe anaphylactic reaction can cause death by respiratory obstruction. During an anaphylactic reaction, the body releases large amounts of histamine and other chemicals, leading to swelling and constriction of the airways. This constriction can cause difficulty in breathing and ultimately lead to respiratory failure if not treated promptly.

Memory T cells are a type of T cells that do not directly participate in the destruction of pathogens. Instead, they are responsible for "remembering" specific antigens that they have encountered before. When the same antigen is presented at a later time, memory T cells can mount a more rapid and efficient immune response, leading to a faster clearance of the pathogen. This is why memory T cells play a crucial role in the body's ability to develop long-lasting immunity against specific pathogens.

Macrophages are immune cells that play a crucial role in antigen presentation. They engulf pathogens through a process called phagocytosis, breaking them down into smaller pieces called antigens. These antigens are then presented on the surface of the macrophage, allowing other immune cells to recognize and mount an immune response against the pathogen. Red blood cells do not have the ability to engulf pathogens, antibodies are molecules produced by the immune system to neutralize pathogens, and vaccines are substances that stimulate the immune system to produce an immune response.

Plasma cells are most related to antibody-mediated immunity because they are the cells responsible for producing and secreting antibodies. Antibodies are proteins that are produced by plasma cells in response to the presence of foreign substances (antigens) in the body. These antibodies then bind to the antigens, marking them for destruction by other immune cells. This process is a key component of the adaptive immune response and helps to protect the body against infections and other diseases.

Anaphylaxis is the correct answer because it refers to a severe hypersensitivity reaction. Anaphylaxis is a potentially life-threatening allergic reaction that occurs rapidly after exposure to an allergen. It can cause symptoms such as difficulty breathing, low blood pressure, hives, and swelling. Immediate medical attention is required to treat anaphylaxis. Cyanosis refers to a bluish discoloration of the skin due to lack of oxygen, immunocompetence refers to the ability of the immune system to respond to antigens, and autoimmunity refers to a condition where the immune system mistakenly attacks the body's own tissues.

Naturally acquired passive immunity is the most related to the placental transfer of antibodies from mother to fetus. During pregnancy, the mother's antibodies are transferred across the placenta to provide temporary protection to the developing fetus. This transfer occurs naturally and passively, meaning that the fetus does not actively produce the antibodies itself. This type of immunity is important for the newborn's protection against various infections in the early months of life until its own immune system develops fully.

An allergen is an antigen. Antigens are substances that can trigger an immune response in the body, leading to the production of antibodies. In the case of allergies, the immune system mistakenly identifies certain harmless substances, such as pollen or pet dander, as harmful antigens. This triggers an allergic reaction, causing symptoms like sneezing, itching, and swelling. Therefore, the correct answer is antigen.

A massive release of histamine can lead to wheezing and hypotension. Histamine is a chemical released by the immune system during an allergic reaction. It causes blood vessels to dilate, resulting in a drop in blood pressure. This can lead to symptoms such as wheezing, which is caused by the narrowing of the airways, and hypotension, which is low blood pressure. Jaundice, anemia, and thrombosis are not directly associated with a massive release of histamine.

Killer T cells destroy pathogens by punching holes in their cell membrane and secreting lymphokines. This allows them to directly kill infected cells and release chemicals that attract other immune cells to the site of infection. Helper T cells, on the other hand, assist in coordinating the immune response. Suppressor T cells regulate the immune response and prevent it from becoming too strong. Memory T cells are responsible for remembering specific pathogens and mounting a faster and stronger response upon re-infection.

Vaccination is a method of introducing a weakened or dead form of a pathogen into the body to stimulate the immune system. This exposure triggers the production of memory cells, which are specialized immune cells that "remember" the specific pathogen and can mount a rapid and effective response if the individual is exposed to the actual pathogen in the future. These memory cells allow for a quicker and stronger immune response, leading to the prevention or reduction of symptoms and the development of immunity against the pathogen.

A booster is a substance or vaccine that increases the production of antibodies in response to a specific antigen. This means that when a booster is administered, it enhances the immune response and helps the body produce more antibodies against a particular antigen. This can be beneficial in providing long-lasting immunity and improving the effectiveness of vaccines or immune responses against specific pathogens.

Plasma cells are derived from B cells. B cells are a type of white blood cell that plays a crucial role in the immune response by producing antibodies. Antibodies are proteins that are produced by plasma cells and are responsible for recognizing and neutralizing foreign substances in the body. Neutrophils and eosinophils are types of granulocytes that are involved in the innate immune response, while T cells are a type of lymphocyte that play a role in cell-mediated immunity. Therefore, B cells are most associated with plasma cells and antibodies.

The group "nonspecific immunity: inflammation, NK cells, fever, T cells" is incorrect because T cells are part of the specific immune response, not the nonspecific immune response. Nonspecific immunity refers to the general defense mechanisms that act against a wide range of pathogens, while specific immunity involves a targeted response to specific pathogens. T cells are a type of white blood cell that play a key role in specific immune responses by recognizing and targeting specific antigens.

A breastfed infant receives antibodies from their mother through breast milk, which provides them with temporary immunity to the same diseases their mother has been exposed to. This type of immunity is known as naturally acquired passive immunity because it is acquired naturally through the transfer of antibodies from the mother to the infant.

B and T cells represent specific immunity because they are both types of white blood cells that play a crucial role in the immune response. B cells are responsible for producing antibodies, which target specific pathogens and help to neutralize them. T cells, on the other hand, directly attack infected cells and regulate the immune response. Both B and T cells are part of the adaptive immune system, which is able to recognize and remember specific pathogens, providing long-term immunity. In contrast, inflammation, interferons, and natural killer cells are components of the innate immune system, which provides immediate, non-specific defense against a wide range of pathogens.

Naturally acquired active immunity is the correct answer because when a person is infected with chickenpox as a child, their immune system produces antibodies to fight off the virus. These antibodies remain in the body and provide long-term protection against future infections. As a result, if the person is exposed to the chickenpox virus again as an adult, their immune system recognizes it and quickly mounts a response, preventing them from getting sick.

T cells are a type of white blood cell that play a crucial role in the immune response. They are responsible for cell-to-cell combat, as they directly attack and destroy infected or abnormal cells in the body. T cells recognize foreign antigens on the surface of infected cells or pathogens, and then release chemical signals or directly kill the target cells. This process helps to eliminate pathogens and prevent the spread of infection. Therefore, T cells are the most appropriate answer for the given statement.

IgE, IgA, and IgG are types of immunoglobulins, also known as antibodies. These antibodies are produced by the immune system in response to the presence of foreign substances, such as bacteria or viruses, in the body. IgE is involved in allergic reactions, IgA is found in mucosal areas like the respiratory and gastrointestinal tracts, and IgG is the most common antibody in the bloodstream. These antibodies play a crucial role in defending the body against infections and other harmful invaders.

Epinephrine is the treatment of choice for an anaphylactic reaction because it acts as a bronchodilator, reduces swelling, and increases blood pressure. It works by stimulating the body's alpha and beta adrenergic receptors, which helps to counteract the severe symptoms of an anaphylactic reaction such as difficulty breathing, low blood pressure, and hives. Epinephrine is a fast-acting medication that can quickly reverse the potentially life-threatening effects of anaphylaxis.

Naturally acquired active immunity is the best description for the immunity to measles if you had measles as a child. This type of immunity occurs when the body's immune system is exposed to the actual disease-causing agent, in this case, the measles virus, and develops a response to it. As a result, the body produces memory cells that recognize and respond to the virus if encountered again in the future, providing long-lasting protection against measles. This is different from passive immunity, which involves receiving pre-formed antibodies from another source, and artificial immunity, which is acquired through vaccination.

HIV attacks and impairs the immune system by targeting helper T cells. These cells play a crucial role in coordinating the immune response by activating other immune cells and producing cytokines. When helper T cells are destroyed by HIV, the immune system becomes weakened and unable to effectively fight off infections and diseases. This ultimately leads to the development of acquired immunodeficiency syndrome (AIDS).

Helper T cells secrete a lymphokine that stimulates both T and B cells. Lymphokines are signaling molecules that are released by immune cells to regulate the immune response. Helper T cells play a crucial role in coordinating the immune response by activating and stimulating other immune cells, including T cells and B cells. They release lymphokines such as interleukins that enhance the proliferation and activation of T and B cells, promoting an effective immune response against pathogens. Therefore, helper T cells are responsible for secreting the lymphokine that stimulates both T and B cells.

Humoral immunity is the correct answer because it refers to the type of immunity that involves the production of antibodies by B cells. These antibodies are carried by the blood and are responsible for neutralizing pathogens and toxins that are present in the body fluids. This type of immunity is distinct from cell-mediated immunity, which involves the activation of T cells to directly attack infected cells. Immunotolerance refers to a state of unresponsiveness to certain antigens, while autoimmunity refers to the immune system attacking the body's own cells and tissues.

Activation of mast cells causes the release of histamine. Mast cells are a type of white blood cell that play a crucial role in the immune response. When mast cells are activated by an allergen or an immune response, they release histamine, which is a chemical mediator. Histamine then triggers various allergic responses, such as inflammation, itching, and vasodilation. This release of histamine is responsible for the symptoms experienced during an allergic reaction, such as sneezing, runny nose, and hives.

The group that is incorrect is "chemical barriers: tears, saliva, stomach acid, B cells, T cells." This is because B cells and T cells are part of the specific immunity response, not the chemical barriers. Chemical barriers refer to substances like tears, saliva, and stomach acid that act as a defense mechanism against pathogens. B cells and T cells, on the other hand, are involved in the specific immune response, where they recognize and attack specific pathogens.

A vaccine conveys active immunity because it stimulates the immune system to produce an immune response against a specific pathogen. This immune response includes the production of antibodies and memory cells that provide long-term protection against future infections by the same pathogen. Unlike gamma globulin or antitoxin, which provide temporary passive immunity through the introduction of pre-formed antibodies, a vaccine activates the body's own immune system to actively fight off infections.

The term that refers to the level of antibodies in your blood is titer. Titer is a measurement of the concentration or amount of antibodies present in the blood sample. It is often used to determine the strength of an immune response or to diagnose certain infections or diseases. T cell count, white blood cell count, and hematocrit are not specifically related to the level of antibodies in the blood.

Phagocytosis is a process where cells engulf and destroy foreign particles or pathogens. It is a function of various cells, including macrophages and neutrophils, not just T cells. Therefore, the statement "Phagocytosis does not require a specific antigen" is correct because phagocytosis can occur without the presence of a specific antigen.

A toxoid is a toxin that has been modified to be harmless while still retaining its ability to stimulate an immune response. This is achieved by treating the toxin with chemicals or heat to denature it, rendering it non-toxic. The resulting toxoid can be used in vaccines to stimulate the production of antibodies against the original toxin, providing immunity without causing illness. Therefore, toxoid is the correct answer to the question.

Contact dermatitis is characterized by a local tissue response to T cell activity. T cells play a crucial role in the immune response and can become activated in response to certain allergens or irritants. In the case of contact dermatitis, T cells are activated by contact with a specific substance, leading to an inflammatory response in the skin. This response can manifest as redness, itching, swelling, and the formation of blisters or rash in the area of contact. Therefore, contact dermatitis is the correct answer as it aligns with the given characteristic of a local tissue response to T cell activity.

The primary response is most associated with a low plasma level of antibodies. During the primary response, the immune system is encountering a specific antigen for the first time. It takes time for the immune system to recognize and respond to the antigen by producing antibodies. Therefore, initially, the plasma level of antibodies is low. As the immune system continues to encounter the antigen, it mounts a stronger and more rapid response, known as the booster response, leading to higher levels of antibodies.