Exam 4: Embryology

A 45-year-old woman is sent to the emergency room after having a widespread tonic-clonic seizure. She has no past history of seizures, but she has just developed right arm weakness. Her family history is noteworthy since her mother died of skin cancer. Physical examination reveals a 13-mm skin lesion on her back, as illustrated in the photograph below. This lesion most likely originated from which of the following embryologic derivatives?

A 24-year-old lady arrives for a normal prenatal scan. Her latest menstrual cycle put her at 19 weeks pregnant. This is the patient's third pregnancy, with no difficulties. Her family background is ordinary, and she has two healthy children. A male baby with bilaterally enlarged fetal kidneys and widespread tiny cysts is seen by ultrasonography. The amount of amniotic fluid is relatively little. There are no further oddities discovered. Which of the following is most likely to be found in the infant after birth?

A 4-year-old child is brought to the office by her parents after they see dark red blood on her toilet tissue following a bowel movement. She has experienced no stomach pain, dysuria, or bowel discomfort. The adolescent has no known medical issues and does not use any drugs. The temperature is 36.7 degrees Celsius (98.1 degrees Fahrenheit), the blood pressure is 100/40 mm Hg, and the pulse rate is 112/min. An examination reveals a soft, nontender abdomen with bowel noises. The hemoglobin concentration is 8 g/dL, and the platelet count is 215,000/mm³. Coagulation tests are common. Using ^99mTc-pertechnetate scintigraphy, sequential imaging reveals focused radiotracer accumulation in the right lower quadrant. Which of the following embryologic processes is most likely to have caused this patient's condition?

In the delivery room, a 1-hour-old baby girl is assessed. Following an easy pregnancy, the baby was delivered at term through spontaneous vaginal delivery. The woman is in her second trimester of pregnancy and has no significant medical history. At 1 and 5 minutes, the Apgar scores were 9 and 9. The patient has been skin-to-skin with her mother and has successfully nursed once. An inspection reveals a rosy, alert baby. Cardiac auscultation demonstrates normal S1 and S2 with no murmurs, as well as normal femoral pulses. Which of the following hemodynamic alterations are most likely to be observed in this infant than before birth?

The concentrations of 2 substances in the amniotic fluid of pregnant women are graphed below. The two curves most likely correspond to which of the following?

After experiencing significant stomach discomfort and vomiting, a 3-year-old kid is taken to the emergency department by his parents. Palpation demonstrates diffuse discomfort, and abdominal imaging reveals a foreign body stuck inside the gut, resulting in a minor intestinal blockage. A laparotomy is conducted to remove the foreign body; an accidental cyst is detected during the surgery. A fibrous ring connects the cyst to the ileum and the umbilicus. Which of the following is related with the embryologic abnormality that led to the creation of this patient's cyst?

A 6-year-old female is being evaluated for persistent hypertension that was discovered incidentally. A week ago, the patient was in her usual check-up, the physician found the blood pressure to be 150/100. During the evaluation, the patient was found to have high blood pressure in the upper arms, while the lower limbs had normal blood pressure. Cardiac examination shows continuous murmur on the back between the scapulae. The problem is in the structure derivative of which of the following embryologic structures?

A two-day-old baby is pale and fussy. He was born to a 22-year-old primigravida who had had only occasional prenatal care. The delivery went smoothly, with Apgar values of 7 and 8 at 1 and 5 minutes, respectively. His temperature is 36.7 degrees Celsius (98 degrees Fahrenheit), his blood pressure is 70/30 mm Hg, his pulse rate is 148 beats per minute, and his respiratory rate is 68 beats per minute. A cyanotic and irritable infant with mild-to-moderate respiratory distress is seen on physical examination. Auscultation indicates a constant, machine-like murmur heard between the scapulae. Serum lactate levels are high. The aorta is shown on an echocardiogram to be anterior, inferior, and to the right of the pulmonary artery. Which of the following embryologic processes is most likely to be at fault for this patient's condition?

A 23-year-old woman with type 1 diabetes and hypothyroidism arrives at the hospital with a preterm, premature rupture of membranes at 30 weeks' gestation. Prenatal vitamins and insulin are among her prescriptions. The vital signs are normal, and the examination reveals a clear vaginal discharge. The cervix of the woman is closed, and she is not having uterine contractions. The following are the laboratory results: Which of the following medications has the greatest positive impact on fetal survival?

A 13-year-old child is brought to the clinic because he is having increasing trouble breathing, hoarseness, and dysphagia. The symptoms began gradually six months ago but have drastically worsened in the last four weeks. There is no skin rash, pharyngeal discomfort, fever, weight loss, or lack of appetite. The patient's medical history is ordinary, and he or she is not on any drugs. He has received all of his planned vaccines. The patient's parents and siblings have no history of major health issues. He has normal vital signs and is in the 70th percentile for height and weight. A big, red lingual tumor is discovered during an oropharyngeal examination. The mass is then excised from the patient; histopathologic preparation of the retrieved tissue is shown in the figure below. Failure of which of the following embryologic processes is most likely responsible for this patient's lesion?

A 32-year-old lady, gravida 2 para 1, with an easy prenatal history, spontaneously delivered a 4.1-kg (9-lb) infant at 39 weeks gestation. At 1 and 5 minutes, Apgar values were 8 and 10, respectively. Additional testing in the neonatal nursery reveals improper sexual differentiation. A 46,XY genotype was discovered during karyotype research. A biopsy of gonadal tissue reveals the absence of Sertoli cells but the presence of adequately functioning Leydig cells. Which of the following traits is the most likely?

A baby girl is assessed in the neonatal intensive care unit for respiratory difficulties. The patient was born at full term by vaginal birth. She has struggled to breathe from infancy, with loud snoring and periodic oxygen deficiency. Because of her respiratory issues, she has been unable to breastfeed. When the patient is placed in a prone posture, his or her breathing improves dramatically. On inspection, there is a tiny mandible, a tongue that is posteriorly displaced, and a U-shaped cleft palate. Which of the following describes the anomalies described?

A 33-year-old man arrives at the clinic after experiencing episodic headaches for many months, which are accompanied by perspiration and anxiety and disappear spontaneously within 15-30 minutes. He has no other medical issues and does not use any medications. His sibling just underwent hyperparathyroidism surgery. The blood pressure is 180/110 mm Hg and the pulse rate is 102/min. The laboratory findings reveal that the serum electrolytes and renal function are normal. An abdominal CT scan indicates a tumor in the right adrenal gland. Which of the following cells shares an embryological origin with the tissue causing this patient's present condition?

A 22-year-old woman, 14 weeks pregnant, visits her doctor for a prenatal appointment. She claims to be in good health, with the exception of occasional moderate weariness. So far, her pregnancy has been trouble-free. The patient's abdomen seems bigger than would be expected at 14 weeks on physical examination. An obstetrical ultrasound reveals male and female twins. Which of the following best defines this patient's form of twin placentation?

A 64-year-old man passes out near the emergency room door. A doctor rushes over to the patient and feels a strong pulse along the inner side of the left sternocleidomastoid muscle. Which of the following aortic arches is the vessel palpated by the doctor a derivative of?

A term baby boy is assessed for respiratory distress in the neonatal intensive care unit. At 1 and 5 minutes, Apgar values are 2 and 5, respectively. Respirations are 84/min. The patient has a barrel chest, a scaphoid abdomen, and slight cyanosis of his limbs on examination. Auscultation reveals that the left lung has no breath sounds; the right lung has normal aeration. A chest x-ray shows several fluid-filled cystic regions on the left, as well as a mediastinal shift to the right. Which of the following embryologic events did not occur in this patient?

A 4-hour-old child with a cleft lip is successfully nursing. The baby was delivered vaginally following a straightforward pregnancy and delivery. At 20 weeks gestation, routine prenatal sonography revealed no abnormalities. Physical examination reveals a palate that is intact and a unilateral cleft lip on the left side. There are no additional abnormalities found. Which of the following intrauterine procedures failed to result in this child's cleft lip?

A 7-year-old child is brought to the clinic for a neck mass assessment. The patient was sent to an urgent care center a week ago for nasal congestion and a sore throat. The symptoms went away after a few days, but his parents noted a persistent bulge in his neck. The patient has no past medical issues and is fully immunized. Physical examination reveals that he is healthy and well-nourished. A somewhat sensitive 2-cm midline lump travels up as the patient swallows, according to a neck examination. Which of the following is the most likely source of the lesion in this patient?

A 32-year-old woman, gravida 1 para 0, at 35 weeks gestation, presents to the emergency room owing to a 24-hour period of no fetal activity. The patient did not get any prenatal treatment. Fetal ultrasound confirms fetal death intrauterine. The fetus' autopsy revealed incomplete separation of the cerebral hemispheres with a single ventricle, as depicted in the figure below: Which of the following is most closely associated with this fetal condition?

At the conclusion of each day, a 32-year-old lady complains of hand weakness and "heaviness" in her eyelids. An anterior mediastinal mass is seen on chest imaging. The organ from which this mass most likely arose has the same embryologic origin as: