1.
Macrophages and Neutrophils play a role in the Innate Immune Reaction
Correct Answer
A. True
Explanation
Macrophages and neutrophils are both types of white blood cells that are part of the innate immune system. They play a crucial role in the initial response to pathogens and foreign substances in the body. Macrophages are responsible for engulfing and destroying pathogens, while neutrophils are the first responders to infection and inflammation. Together, these cells help to initiate and coordinate the innate immune response, which is the body's first line of defense against infections. Therefore, it is true that macrophages and neutrophils play a role in the innate immune reaction.
2.
Vasoactive and Chemotactic factors do what?
Correct Answer
A. Trigger an Increase in blood flow and capillary permeability
Explanation
Vasoactive and chemotactic factors are substances that can trigger an increase in blood flow and capillary permeability. This means that they can cause blood vessels to dilate, allowing more blood to flow through them, and also make the capillary walls more permeable, allowing fluids and immune cells to move more easily between the blood vessels and surrounding tissues. This response is part of the body's immune and inflammatory processes, helping to bring more immune cells to the site of infection or injury and facilitate their movement into the affected tissues.
3.
Phagocytes migrate to sites of inflammation via what process?
Correct Answer
A. Chemotaxis
Explanation
Phagocytes migrate to sites of inflammation via chemotaxis, which is the process of moving towards a chemical signal. Inflammation releases chemical signals called chemotactic factors, which attract phagocytes to the site of injury or infection. This directional movement allows phagocytes to reach the site quickly and efficiently, aiding in the immune response and the removal of pathogens or damaged cells.
4.
Which of the following is NOT a phagocyte?
Correct Answer
D. Natural Killer Cell
Explanation
Natural Killer Cells are not phagocytes. Phagocytes are a type of immune cell that can engulf and destroy pathogens, while Natural Killer Cells are a type of lymphocyte that primarily target and kill virus-infected cells and tumor cells through the release of toxic substances.
5.
The innate immune reaction is more specific than the adaptive immune reaction
Correct Answer
B. False
Explanation
The statement is false because the adaptive immune reaction is actually more specific than the innate immune reaction. The adaptive immune system is able to recognize and target specific pathogens or antigens by producing highly specialized immune cells called lymphocytes. These lymphocytes undergo a process of maturation and selection, resulting in the production of specific antibodies or T cells that can recognize and destroy specific pathogens. In contrast, the innate immune system relies on general mechanisms such as inflammation and phagocytosis to respond to a wide range of pathogens, but it lacks the ability to specifically target individual pathogens.
6.
A virus infects a cell's cytoplasm which of the following immune response components could deal with this problem?
Correct Answer
D. NK Cells
Explanation
NK cells, also known as natural killer cells, are a type of lymphocyte that play a crucial role in the immune response against viral infections. They are capable of recognizing and destroying virus-infected cells directly, without the need for prior activation or antigen presentation. NK cells recognize infected cells by detecting changes in the surface markers of the infected cells, such as the downregulation of MHC class I molecules. Once identified, NK cells release cytotoxic granules containing perforin and granzymes, which induce apoptosis in the infected cells. Therefore, NK cells are an important component of the immune response that can effectively deal with a virus infecting a cell's cytoplasm.
7.
Which of the following is an indirect mechanism of tissue damage by pathogens
Correct Answer
D. Immune complexes
Explanation
Immune complexes can lead to tissue damage indirectly by triggering an immune response that causes inflammation. When pathogens enter the body, the immune system produces antibodies to neutralize them. However, in some cases, the antibodies can form complexes with the pathogens, leading to the activation of immune cells and the release of inflammatory mediators. This immune response can cause damage to surrounding tissues, leading to inflammation and tissue destruction. Therefore, immune complexes can be considered an indirect mechanism of tissue damage by pathogens.
8.
Innate Immune receptors are clonally distributed
Correct Answer
B. False
Explanation
Innate immune receptors are not clonally distributed. Clonal distribution refers to the distribution of receptors in a specific pattern or arrangement, which is not the case for innate immune receptors. Innate immune receptors are instead expressed on a wide range of cells and are not restricted to specific clones. Therefore, the correct answer is false.
9.
Most Microorganisms express repeating patterns of molecular structures termed:
Correct Answer
A. Pathogen Associated Molecular Patterns (PAMPs)
Explanation
Microorganisms express repeating patterns of molecular structures called Pathogen Associated Molecular Patterns (PAMPs). These patterns are recognized by the immune system through specific receptors called Pattern Recognition Receptors (PRRs). PAMPs help the immune system identify and respond to potential pathogens, triggering an immune response to eliminate the invading microorganisms. The other options, Patterned Histocompatibility Series (PHS) and Nannose Effected Linking Sections (NELS), are not valid terms or concepts related to the recognition of molecular patterns by microorganisms.
10.
Cells have cytopolasmic receptors to help sense viral nucleic acid
Correct Answer
A. True
Explanation
Cells have cytoplasmic receptors to help sense viral nucleic acid. This statement is true. Cytoplasmic receptors play a crucial role in the innate immune response by recognizing viral nucleic acids, such as viral RNA or DNA, that are present in the cytoplasm of infected cells. These receptors can detect the presence of viral nucleic acids and initiate a signaling cascade that leads to the activation of antiviral defense mechanisms, including the production of interferons and the induction of an inflammatory response. This helps the cell to recognize and respond to viral infections, aiding in the elimination of the virus and the protection of the host organism.
11.
Interleukin 1 does which of the following?
Correct Answer
A. Stimulates inflammation and fever
Explanation
Interleukin 1 is a cytokine that is released by immune cells in response to infection or injury. It plays a crucial role in initiating the inflammatory response by promoting the recruitment of immune cells to the site of infection or injury. Additionally, interleukin 1 also stimulates the production of other inflammatory molecules, such as prostaglandins and cytokines, which further contribute to the inflammatory process. Fever is another response triggered by interleukin 1, as it acts on the hypothalamus to increase body temperature. Therefore, the correct answer is that interleukin 1 stimulates inflammation and fever.
12.
Which of the following is NOT a mechanism in phagocytosis?
Correct Answer
D. Toxic chelation
Explanation
Toxic chelation is not a mechanism in phagocytosis. Phagocytosis is the process by which cells engulf and ingest foreign particles or pathogens. Acidification occurs when the phagosome, the vesicle formed during phagocytosis, becomes more acidic, which helps in killing the engulfed microorganism. Toxic nitrogen oxides and antimicrobial peptides are both involved in the destruction of the engulfed microorganism. However, toxic chelation, which refers to the binding of metal ions to prevent their use by the microorganism, is not a mechanism in phagocytosis.
13.
Chronic Granulomatous Diseas is caused by:
Correct Answer
A. Mutation in NADpH oxidase complex
Explanation
Chronic Granulomatous Disease is caused by a mutation in the NADPH oxidase complex. This complex is responsible for producing reactive oxygen species (ROS) that help to kill bacteria and fungi in the body. When there is a mutation in this complex, it impairs the ability of immune cells to produce ROS, leading to an increased susceptibility to infections. This genetic defect affects the function of phagocytes, which are a type of white blood cell involved in the body's immune response.
14.
Cytokines can function in an autocrine or paracrine manner
Correct Answer
A. True
Explanation
Cytokines are small proteins that play a crucial role in cell signaling and communication within the immune system. They can act in an autocrine manner, meaning they can bind to receptors on the same cell that produced them, influencing their own activity. Additionally, cytokines can function in a paracrine manner, where they can travel to nearby cells and bind to their receptors, affecting their behavior. Therefore, the statement that cytokines can function in an autocrine or paracrine manner is true.
15.
Chemokines are specific in receptor usage
Correct Answer
B. False
Explanation
Chemokines are not specific in receptor usage. Chemokines are a family of small proteins that play a key role in immune responses by attracting immune cells to sites of infection or inflammation. They bind to specific receptors on the surface of immune cells, triggering a signaling cascade that leads to cell migration. However, chemokines can also bind to multiple receptors, and different chemokines can bind to the same receptor. This versatility in receptor usage allows for a complex and dynamic regulation of immune cell movement and function. Therefore, the statement that chemokines are specific in receptor usage is false.