Nokea
An older adult has fallen and sprained his ankle in a local park. Which action should the responder perform first?
- A. Elevate the foot.
- B. Apply ice.
- C. Administer aspirin.
- D. Assist the patient with ambulation.
Correct Answer: A
Rationale: The correct action is to elevate the foot first. Elevating the foot helps reduce swelling and pain by promoting better circulation. This step is crucial in the initial management of a sprained ankle. Applying ice and administering aspirin can come after elevating the foot. Assisting with ambulation should only be considered after the initial measures are taken to address the sprained ankle.
You may also like to solve these questions
What is a granuloma?
- A. A type of antibody
- B. A collection of macrophages filled with antigens
- C. A cluster of mast cells
- D. An antibody-antigen complex
Correct Answer: B
Rationale: The correct answer is B: A collection of macrophages filled with antigens. Granulomas are tissue responses to chronic inflammation, where macrophages form a cluster to engulf and contain foreign substances like antigens. This leads to the formation of a granuloma, which can be seen in conditions like tuberculosis. Other choices are incorrect because: A) Antibodies are proteins produced by the immune system, not structures like granulomas; C) Mast cells are involved in allergic reactions and not typically associated with granulomas; D) An antibody-antigen complex is a different concept related to immune response but not specific to granulomas.
Which cells are responsible for antigen presentation to T cells?
- A. Plasma cells
- B. Antigen-presenting cells (APCs)
- C. NK cells
- D. Eosinophils
Correct Answer: B
Rationale: The correct answer is B: Antigen-presenting cells (APCs). APCs, such as dendritic cells, macrophages, and B cells, are specialized cells that capture, process, and present antigens to T cells to initiate an immune response. They express major histocompatibility complex (MHC) molecules for antigen presentation. Plasma cells (A) produce antibodies, NK cells (C) are involved in killing infected cells, and eosinophils (D) are primarily involved in parasitic infections and allergic responses, not antigen presentation to T cells.
Which molecule is essential for antigen presentation to T cells?
- A. Antibody
- B. Major Histocompatibility Complex (MHC)
- C. Complement protein C3
- D. Cytokines
Correct Answer: B
Rationale: The correct answer is B: Major Histocompatibility Complex (MHC). MHC molecules present antigens to T cells for immune response activation. They bind to antigenic peptides and present them on the cell surface for recognition by T cells. This is crucial for the immune system to distinguish between self and non-self antigens. Antibodies (A) are produced by B cells and do not directly present antigens to T cells. Complement protein C3 (C) is involved in the complement system for immune defense, not antigen presentation. Cytokines (D) are signaling molecules that regulate immune responses but do not directly present antigens to T cells.
Which of the following is NOT true? The meeting of naïve T cells and dendritic cells:
- A. Is facilitated by the presence of naïve B cells
- B. Occurs in the paracortex of lymph nodes
- C. Is facilitated by movement of the T cell along connective tissue networks
- D. May supply the T cell with activation Signal 1
Correct Answer: A
Rationale: The correct answer is A because the meeting of naïve T cells and dendritic cells is not facilitated by the presence of naïve B cells. Naïve T cells interact with dendritic cells in the paracortex of lymph nodes, not with naïve B cells. The movement of T cells along connective tissue networks aids in their interaction with dendritic cells, and this interaction may supply the T cell with activation Signal 1, which is essential for T cell activation. Overall, the incorrect choices (B, C, and D) are actually true statements regarding the meeting of naïve T cells and dendritic cells, making them incorrect options.
What are the characteristics of the carbonic acid–bicarbonate buffer system (select all that apply)?
- A. CO2 is eliminated by the lung
- B. Neutralizes HCl acid to yield carbonic acid and salt
- C. H2CO3 formed by neutralization dissociates into H2O and CO2
- D. Shifts H+ in and out of cell in exchange for other cations such as potassium and sodium
Correct Answer: A
Rationale: This buffer system eliminates CO2 via lungs, neutralizes acids/bases, shifts hydrogen ions across membranes, and maintains pH balance.