Nokea
A hybridoma:
- A. Secretes both polyclonal and monoclonal antibodies
- B. Is generated from the fusion of two antigen-activated B cells
- C. Can live in tissue culture indefinitely
- D. All of these options describe a hybridoma
Correct Answer: C
Rationale: Step-by-step rationale:
1. Hybridoma is a cell line formed by the fusion of a B cell (producing a specific antibody) and a myeloma cell.
2. Choice C is correct because hybridomas can be immortalized and cultured indefinitely.
3. Choice A is incorrect because hybridomas produce monoclonal antibodies, not polyclonal antibodies.
4. Choice B is incorrect because hybridomas are formed from a single B cell and a myeloma cell, not two antigen-activated B cells.
5. Choice D is incorrect as only option C accurately describes a hybridoma's characteristic of indefinite tissue culture survival.
You may also like to solve these questions
Select the correct number of statements that are true.
- A. Only 1 and 3 are correct.
- B. Only 2 and 4 are correct.
- C. Only 3 and 4 are correct.
- D. All of the above are correct.
Correct Answer: A
Rationale: The correct answer is A. Statement 1 and 3 are true because selecting them would result in a correct answer. Statement 2 is incorrect as it claims that only 2 and 4 are correct, which contradicts the correct answer. Statement 4 is also incorrect as it claims that only 3 and 4 are correct, which is not consistent with the correct answer. The option "All of the above are correct" (D) is false because it includes statement 2, which is incorrect. Therefore, A is the correct choice because it accurately identifies the true statements.
Acquired immunity is a result of previous exposure
- A. serious illness
- B. to vaccination
- C. repeated exposure to the same factor
- D. treatment with penicillin
Correct Answer: B
Rationale: The correct answer is B: to vaccination. Acquired immunity is the immune response developed after exposure to a vaccine, which stimulates the immune system to recognize and remember specific pathogens. Vaccination helps the body build immunity without causing serious illness like choice A, without requiring repeated exposure like choice C, and without being related to treatment with penicillin like choice D. Vaccination mimics natural infection, prompting the body to produce memory cells that can respond more effectively when encountering the actual pathogen in the future.
Alumn is an adjuvant that triggers
- A. TLR4
- B. DAMPs formation
- C. NOD1
- D. TLR9
Correct Answer: B
Rationale: The correct answer is B: DAMPs formation. Alum is known to trigger the release of damage-associated molecular patterns (DAMPs), which are endogenous molecules released by damaged cells. This activation of DAMPs plays a crucial role in initiating and enhancing the immune response. The other choices, TLR4, NOD1, and TLR9, are receptors involved in recognizing specific pathogen-associated molecular patterns (PAMPs) rather than DAMPs. Therefore, they are not directly triggered by alum. This makes choice B the correct answer based on the known mechanism of action of alum as an adjuvant.
Which of the following is not an outcome of phagocytosis in macrophages
- A. Respiratory burst
- B. Nitric oxide production
- C. Antigen presentation
- D. Complement activation
Correct Answer: D
Rationale: The correct answer is D: Complement activation. Phagocytosis by macrophages involves engulfing and digesting pathogens. Complement activation occurs through a separate pathway involving a series of proteins that enhance the immune response. Phagocytosis does not directly lead to complement activation. Choices A, B, and C are outcomes of phagocytosis in macrophages: Respiratory burst involves production of reactive oxygen species, nitric oxide production helps destroy pathogens, and antigen presentation is important for activating other immune cells.
Which immune system function is most relevant to cancer?
- A. Suppressing cytokine release
- B. Promoting adaptive immunity only
- C. Identifying and eliminating abnormal cells
- D. Limiting the effectiveness of phagocytes
Correct Answer: C
Rationale: The correct answer is C: Identifying and eliminating abnormal cells. This function is most relevant to cancer because the immune system's ability to recognize and destroy abnormal cells is crucial in preventing the development and spread of cancer. The immune system constantly surveys the body for cells that have mutated or become cancerous, and when identified, it initiates an immune response to eliminate them. This process is essential for maintaining the body's health and preventing cancerous cells from proliferating.
Choice A (Suppressing cytokine release) is incorrect because cytokines play a role in regulating the immune response, which can be important in cancer immunity. Choice B (Promoting adaptive immunity only) is incorrect as both innate and adaptive immune responses are involved in combating cancer. Choice D (Limiting the effectiveness of phagocytes) is incorrect as phagocytes are important in recognizing and destroying cancer cells.