Which of the following DNA polymerases cleaves a DNA sequence at the direction of 5' → 3'?

Correct Answer: A

Rationale: The correct answer is A: DNA polymerase I. DNA polymerase I has both 5' to 3' polymerase activity and 5' to 3' exonuclease activity, allowing it to cleave DNA in the 5' to 3' direction. This enzyme can remove RNA primers during DNA replication by cleaving them in the 5' to 3' direction and replace them with DNA nucleotides. DNA polymerase II, III, and IV do not have the same exonuclease activity as DNA polymerase I, so they are not capable of cleaving DNA sequences in the 5' to 3' direction like DNA polymerase I.

Correct Answer: A

Rationale: The correct answer is A: Calf intestinal phosphatase. This enzyme removes 5' phosphate groups from DNA molecules, preventing self-ligation of restricted plasmid vectors. This step is crucial in generating linearized vectors for downstream applications. Pyrophosphatase (B) hydrolyzes pyrophosphate bonds, not 5' phosphate groups. Phosphohydrolase (C) is a general term for enzymes that hydrolyze phosphoester bonds, not specific to 5' phosphate removal. Phosphate exonuclease (D) degrades nucleic acids by removing nucleotides from the 3' end, not the 5' phosphate group.

Correct Answer: B

Rationale: The correct answer is B) Monitor client for infusion reactions. When caring for a client with an immune system disorder, it is crucial to monitor them for infusion reactions, as many medications used to treat immune disorders are administered via infusion and can trigger adverse reactions. Monitoring for signs of infusion reactions promptly can prevent serious complications and ensure the client's safety. Option A) Monitor client for depression is incorrect because while mental health is important in overall patient care, it is not directly related to managing immune system disorders. Option C) Review drug references is also incorrect as it is a general action that may be applicable in various nursing scenarios but is not specifically crucial for clients with immune system disorders. Option D) Advise the client on modifying the home environment is not the essential nursing action for immune system disorders. While creating a safe and supportive home environment is important for overall health, it is not as critical as monitoring for potential infusion reactions in this context. Educational Context: Understanding the priority nursing actions for clients with immune system disorders is vital for nurses to provide safe and effective care. By prioritizing monitoring for infusion reactions, nurses can intervene promptly and prevent potential complications, highlighting the importance of vigilant assessment and proactive care in managing these complex conditions.

Correct Answer: C

Rationale: In this scenario, the correct answer is option C: Being in crowds during the periods of immunosuppression. Clients with autoimmune disorders have overactive immune systems that mistakenly attack their own tissues. During periods of immunosuppression, where the immune system is intentionally suppressed to manage the autoimmune response, it is crucial for the client to avoid being in crowded places where they are at a higher risk of exposure to infectious agents. This is because their weakened immune system may not be able to effectively fight off infections, leading to serious complications. Option A, resting during severe exacerbation, is important for managing symptoms but does not directly relate to the client's risk of infection. Option B, regular exercise during remission, is generally encouraged as it can have benefits for overall health and immune function. Option D, a humid environment during remission, does not have a direct correlation with increased risk of infections in clients with autoimmune disorders. Educationally, understanding the importance of managing environmental exposure in clients with autoimmune disorders is crucial for nursing students. It emphasizes the need for preventive measures to protect these individuals from potential complications related to infections during periods of immunosuppression. This knowledge is vital in providing safe and effective care for clients with autoimmune disorders.

Correct Answer: A

Rationale: The correct answer is A) Complying with the timing of antiviral medications around meals. This instruction is crucial because certain antiviral medications need to be taken with or without food to optimize absorption, reduce side effects, and maintain consistent blood levels of the drug for effectiveness in managing HIV. Option B) Avoiding exposure to harsh sunlight for about two hours after taking the medication is incorrect. While sunlight exposure may be a concern for some medications due to photosensitivity reactions, it is not a general rule for antiviral drugs used in HIV treatment. Option C) Having the medications with plenty of fruit juice is incorrect. Fruit juice may interact with some medications, altering their absorption or effectiveness. It is important to follow specific instructions provided by healthcare providers. Option D) Having an increased dose of the medications if the symptoms worsen is incorrect. Adjusting medication dosages should only be done under the guidance of a healthcare provider. Increasing doses without medical advice can lead to adverse effects or drug resistance. In an educational context, understanding the correct administration of antiviral medications in HIV treatment is crucial for achieving therapeutic outcomes. Nurses play a vital role in educating patients on proper medication administration to ensure treatment success and minimize risks of complications. Adherence to medication schedules is essential in managing chronic conditions like HIV to maintain viral suppression and prevent disease progression.