Mitochondrial DNA

Correct Answer: B

Rationale: In the context of pediatric nursing and cardiovascular disorders, understanding the role of mitochondrial DNA is crucial. The correct answer is B) Is responsible for some forms of myopathies. Mitochondrial DNA is unique as it has its own genome separate from the nuclear DNA. This genetic material is responsible for encoding essential proteins involved in energy production within the mitochondria. Mutations in mitochondrial DNA can lead to various disorders, including myopathies, which affect muscle function. Option A) Has its own genome is partially correct but does not directly address the specific role of mitochondrial DNA in myopathies. Option C) Can transmit diseases from parents to children is also true as mitochondrial DNA is inherited maternally and mutations can be passed on to offspring, but it does not specifically highlight its association with myopathies. Option D) Is present in neurons is incorrect as mitochondrial DNA is present in almost all cells of the body, not just neurons. Educationally, this question highlights the importance of understanding the unique characteristics and functions of mitochondrial DNA in the context of pediatric cardiovascular disorders. Nurses caring for pediatric patients with mitochondrial myopathies need to be aware of the genetic implications and how they can impact a child's health and development. This knowledge informs their assessment, care planning, and education for both the child and their family.

Correct Answer: B

Rationale: In pediatric nursing, understanding pharmacology is crucial in managing cardiovascular disorders effectively. Proximal renal tubular functions play a vital role in maintaining fluid and electrolyte balance in the body. The correct answer is B) Sodium reabsorption. The proximal renal tubule is responsible for reabsorbing approximately two-thirds of the filtered sodium load. This process is essential for regulating blood volume, blood pressure, and electrolyte balance in the body, especially in pediatric patients with cardiovascular disorders. Option A) HCO3 secretion is not a function of the proximal renal tubule. Hydrogen ions are secreted in exchange for reabsorption of bicarbonate in the proximal tubule to maintain acid-base balance. Option C) Ammonia production primarily occurs in the distal renal tubule to regulate acid-base balance, not in the proximal tubule. Option D) Urine concentration is mainly regulated in the distal nephron segments, not in the proximal tubule. Educationally, understanding the specific functions of different renal tubular segments is essential for nurses caring for pediatric patients with cardiovascular disorders. This knowledge helps in assessing renal function, managing electrolyte imbalances, and evaluating the effectiveness of pharmacological interventions targeted at the renal system.

Correct Answer: A

Rationale: In pediatric nursing, understanding pharmacology is crucial when managing cardiovascular disorders. The correct answer is A) Renin. Renin is a potent vasoconstrictor as it initiates the renin-angiotensin-aldosterone system (RAAS), leading to the production of angiotensin II, a powerful vasoconstrictor that increases blood pressure. Option B) Angiotensin I is incorrect as it is a precursor to angiotensin II and does not possess vasoconstrictive properties. Option C) Nitric oxide is a potent vasodilator, not a vasoconstrictor, playing a key role in regulating vascular tone. Option D) PGI2 (prostacyclin) is also a vasodilator and an inhibitor of platelet aggregation, exerting opposite effects to vasoconstriction. Educationally, grasping the mechanisms of vasoconstriction and vasodilation is vital for managing pediatric cardiovascular conditions. Knowing the actions of specific vasoactive substances helps in selecting appropriate pharmacological interventions to stabilize hemodynamics in pediatric patients with cardiovascular disorders.

Correct Answer: B

Rationale: In the context of pediatric nursing and cardiovascular disorders, understanding hemolytic anemia is crucial. The correct answer is B) Haemosiderinuria. Hemolytic anemia is characterized by the premature destruction of red blood cells, leading to the release of hemoglobin into the bloodstream. Haemosiderinuria, the presence of hemosiderin (a byproduct of hemoglobin breakdown) in the urine, is a key indicator of intravascular hemolysis, a common feature of hemolytic anemia. Option A) Increased haptoglobin is incorrect because in hemolytic anemia, haptoglobin levels are decreased due to the binding of free hemoglobin. Option C) Polychromasia is a feature seen in conditions like iron deficiency anemia, not specifically in hemolytic anemia. Option D) Megaloblastic bone marrow is associated with vitamin B12 or folate deficiencies, not hemolytic anemia. Educationally, understanding the pathophysiology and clinical manifestations of hemolytic anemia in pediatric patients is essential for nurses to provide effective care. Recognizing key laboratory findings like haemosiderinuria can aid in early diagnosis and intervention, ultimately improving patient outcomes.

Correct Answer: D

Rationale: In the most common type of Congenital Adrenal Hyperplasia (CAH), which is 21-hydroxylase deficiency, the correct answer is D) 17-OH progesterone is increased. This is because 21-hydroxylase is essential for cortisol production, and its deficiency leads to a build-up of precursors like 17-OH progesterone, resulting in the characteristic hormonal imbalances seen in CAH. Option A) Autosomal dominant transmission occurs is incorrect because CAH is an autosomal recessive disorder, meaning two copies of the defective gene are needed for the condition to manifest. Option B) II -Hydroxylase is deficient is incorrect as II-hydroxylase deficiency is a different subtype of CAH, not the most common type. Option C) Hypertension is seen is incorrect because although hypertension can be a complication of CAH due to mineralocorticoid deficiency, it is not a defining feature of the most common type of CAH. Understanding the specifics of CAH subtypes and their associated biochemical abnormalities is crucial in pediatric nursing, especially when managing patients with endocrine disorders. Recognizing the correct diagnostic markers like elevated 17-OH progesterone levels in 21-hydroxylase deficiency is vital for accurate diagnosis and appropriate treatment interventions in pediatric patients with CAH.