Erythroblastosis fetalis may occur in:
A second Rh-negative fetus developing in an Rh-negative woman.
A second Rh-positive fetus developing in an Rh-negative woman.
A first Rh-positive fetus developing in an Rh-negative woman.
A first Rh-negative fetus developing in an Rh-negative woman.
The Correct Answer is B
This is because erythroblastosis fetalis, also known as hemolytic disease of the newborn, is caused by Rh incompatibility between the mother and the fetus.
Rh incompatibility occurs when a Rh-negative mother is impregnated by a Rh-positive father, resulting in a Rh-positive fetus.
The mother’s immune system can detect the Rh factor on the fetus’s red blood cells as foreign and produce antibodies against them.
These antibodies can cross the placenta and destroy the fetus’s red blood cells, causing anemia, jaundice, edema, and other complications.
Choice A is wrong because a second Rh-negative fetus developing in an Rh-negative woman will not cause erythroblastosis fetalis.
The mother and the fetus have the same Rh factor, so there is no immune reaction.
Choice C is wrong because a first Rh-positive fetus developing in an Rh-negative woman will not cause erythroblastosis fetalis.
The mother’s immune system will not produce antibodies against the Rh factor until after the first exposure to it, which usually happens during delivery.
Therefore, the first pregnancy is usually unaffected.
Choice D is wrong because a first Rh-negative fetus developing in an Rh-negative woman will not cause erythroblastosis fetalis.
The mother and the fetus have the same Rh factor, so there is no immune reaction.
The normal range of red blood cell count for newborns is 4.1 to 6.1 million cells per microliter of blood.
The normal range of bilirubin level for newborns is 0.3 to 1.9 milligrams per deciliter of blood.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is C
Explanation
Positive feedback mechanisms move conditions away from the normal state.
They amplify the original action and produce more of the same effect.
For example, blood clotting and childbirth are positive feedback mechanisms.
Choice A is wrong because positive feedback mechanisms usually produce unstable conditions.
They do not resist change but rather enhance it.
Choice B is wrong because positive feedback mechanisms do not cause long-term changes.
They are ultimately stopped by negative feedback loops once the process they were used for is complete.
Choice D is wrong because positive feedback mechanisms do not bring conditions back to the normal state.
That is the role of negative feedback mechanisms, which oppose the stimulus and restore homeostasis.
Correct Answer is A
Explanation
Calcitonin is a hormone that protects against excessive blood calcium levels by inhibiting bone turnover and decreasing reabsorption.
It is produced by the thyroid gland and acts on both osteoclasts and osteoblasts.
Choice B is wrong because parathyroid hormone (PTH) stimulates both resorption and formation of bone, and controls the level of calcium in the blood.
Choice C is wrong because thyroxine is a thyroid hormone that is required for skeletal maturation and influences adult bone maintenance but does not directly affect calcium deposition into bone.
Choice D is wrong because insulin is a hormone that regulates both bone formation and bone resorption but does not specifically stimulate calcium deposition into bone.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today