Nokea
Ribosomes associated with cells or organelles have a certain size, which is expressed in Svedberg units. Which associations are incorrect?
- A. cyanobacteria - 80s
- B. chloroplasts - 60s
- C. photosynthetic bacteria - 80s
- D. green algal cytoplasm - 80s
Correct Answer: A
Rationale: The correct answer is A because cyanobacteria have ribosomes measured in 70s, not 80s. Ribosomes in prokaryotes are either 70s (composed of 50s and 30s subunits) or 80s in eukaryotes (60s and 40s subunits). Choices B, C, and D are incorrect because chloroplasts, photosynthetic bacteria, and green algal cytoplasm all have ribosomes measured in 70s or 80s, consistent with their cell types.
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A client with AIDS is experiencing bouts of diarrhea,anorexia,nausea and vomiting. Cryptosporidiosis is diagnosed and the nurse goes to hang the first antibiotic. Which type of macrolide antibiotic is the nurse going to hang?
- A. Humatin
- B. Azithromycin
- C. Penicillin
- D. Ancef
Correct Answer: B
Rationale: Azithromycin is a macrolide antibiotic commonly used to treat cryptosporidiosis in AIDS patients.
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 represents a correct grouping with respect to the target of an immune response, immune response strength, and resulting health status?
- A. Self-antigen, weak response, autoimmune disease
- B. Pathogen, strong response, recurrent infection
- C. Tumour antigen, weak response, cancer
- D. Transplanted organ, strong response, graft acceptance
Correct Answer: C
Rationale: Rationale:
1. Tumor antigens are non-self antigens that trigger a weak immune response due to immune tolerance.
2. Weak immune response against tumor antigens may lead to uncontrolled cell growth, resulting in cancer.
3. Strong immune responses are typically mounted against pathogens to clear infections.
4. Self-antigens should not trigger immune responses to prevent autoimmune diseases.
5. Transplanted organs can elicit strong immune responses leading to rejection, not acceptance.
Summary:
A - Incorrect: Self-antigens should not elicit immune responses to prevent autoimmune diseases.
B - Incorrect: Pathogens typically trigger strong immune responses to clear infections, not recurrent ones.
D - Incorrect: Transplanted organs often lead to strong immune responses and rejection, not acceptance.
Cancer cells go through stages of development. What accurately describes the stage of promotion (select all that apply)?
- A. Obesity is an example of a promoting factor
- B. The stage is characterized by increased growth rate and metastasis
- C. Withdrawal of promoting factors will reduce the risk of cancer development
- D. Tobacco smoke is a complete carcinogen that is capable of both initiation and promotion
Correct Answer: C
Rationale: Promotion involves enhancing the growth of initiated cells. Obesity and tobacco smoke are examples of promoting factors, and withdrawal of such factors can reduce cancer risk.
Your patient with rheumatoid arthritis (RA) is taking prednisone (Deltasone) and naproxen (Alleve) to reduce inflammation and joint pain. Which of these symptoms is the strongest indicator that a change in therapy may be necessary?
- A. The patient states that the RA symptoms are worst in the morning.
- B. The patient complains about having dry eyes.
- C. The patient has round and moveable nodules just under the skin.
- D. The patient has stools that are very dark in color.
Correct Answer: D
Rationale: Dark stools can indicate gastrointestinal bleeding which is a serious side effect of NSAIDs like naproxen. This requires immediate attention and possibly a change in therapy. The other symptoms while related to RA do not indicate an urgent need for a change in treatment.