USMLE RX

Question 1

Wide spaced eyes and epicentral folds, with one fewer crease in palm that expected; eye examination shows white spots on the peripheral iris and extra autosomal chromosome. A/w with duodenal atresia

Answer 1

Down syndrome

Question 2

What autosomal trisomy is a/w holoprosencephaly?

Answer 2

patau syndrome; trisomy 13

Question 3

What autosomal trisomy is a/w ALL?

Answer 3

21

Question 4

_____ is associated with midline facial defects such as cleft lip/palate and with coloboma (missing tissue in the risk, retina, choroid, or optic nerve), and is most commonly seen with trisomy 21?

Answer 4

holoprosencephaly

Question 5

Malignant melanoma, characterized by irregular borders, ulceration, radial and vertical growth, and sun exposed location, originates from?

Answer 5

neural crest cells (melanocytes)

Question 6

elevated AFP levels in amniotic fluid and maternal serum can be a sign of what?

Answer 6

neural tube defects such as meningocele and meningomyelocele

Question 7

What are the 23 (1N, 1C) cells that are formed from secondary spermatocytes after meiosis 2 is completed. They undergo morphologic changes to become mature sperm that include acrosome, head, neck and tail.

Answer 7

spermatids

Question 8

The arytenoid cartilages arise as swellings form what embryological orgin at 32 days of gestation?

Answer 8

6th pharyngeal arch

Question 9

In the absence of mullerian inhibitory factor, the mullerian ducts develop into:

Answer 9

the Fallopian tubes, the uterus and the superior proximal portion of the vagina

Question 10

In the presence of MIF, which is produced and secreted by the Sertoli cells, the mullerian ducts degenerate but may remain as vestigial remnant called

Answer 10

the appendix testes

Question 11

The mesonephric ducts develop into the male internal genital structures, with the exception of the prostate from the urogenital sinus. Remember what structures?

Answer 11

BEEDS: bladder trigone, epididymis, ejaculatory duct, ductus deferens, seminal vesicles

Question 12

Mediastinal deviation can occur with a diaphragmatic hernia, with mediastinal deviation in what direction from of the herniation,almost always the left hemithorax

Answer 12

away from the side of the herniation

Question 13

Failure of the diaphragm to properly form and close leads to

Answer 13

congenital diaphragmatic hernia

Question 14

true/false: Herniation of the bowel into the thorax may cause a shift in mediastinal structures to the contralateral hemithorax, which can manifest as heart sounds best appreciated in the right hemithorax.

Answer 14

true

Question 15

developing diaphragm develops from

Answer 15

septum transversum, pleuroperitoneal folds, body wall, and dorsal mesentery of the esophagus

Question 16

Failure of _____ to form leads to diaphragmatic hernias, with bowel sounds in lung zones

Answer 16

pleuroperitoneal folds (membrane)

Question 17

Turner syndrome patients have coarctation of the aorta, a congenital narrowing of the descending aorta, usually just distal to the origin of the left subclavian artery and opposite to the dual arteriosus. what kind of coarctation is this?

Answer 17

juxtaductal coarctation

Question 18

what can result in a small left arm due to compromised blood flow if the left subclavian artery is involved

Answer 18

juxtaductal coarctation

Question 19

Beta hCG has a distinctive alpha subunit; which it shares with what other hormones?

Answer 19

TSH, LH, and FSH

Question 20

acute onset abdominal pain with/without rebound tenderness. what to include in your differential?

Answer 20

ectopic pregnancy

Question 21

What can result in deafness, PDA, pulmonary artery stenosis,cataracts and microcephaly?

Answer 21

congenital rubella infection

Question 22

Bone deformity of the nasal bridge or saddle nose, is seen in what?

Answer 22

congenitally acquired syphilis

Question 23

What condition can impinge on the crossing fibers of the spinothalamic tract, resulting in bilateral loss of pain and temperature sensation in the upper extremities?

Answer 23

syringomyelia

Question 24

Inability to pass meconium and the finding of an empty rectum?

Answer 24

hirschprung disease or congenital megacolon

Question 25

failure of neural crest cells to migrate into the bowel wall during embryogenesis and is characterized by the absence of ganglion cells in the large bowel , typically in the rectum and the adjacent segment of the distal colon that is immediately proximal to the rectum.

Answer 25

Hirschsprung disease or congenital megacolon

Question 26

Folic acid is a coenzyme for 1 carbon transfers, decreases what in the fetus when taken in adequate amounts by the mother ?

Answer 26

neural tube defects ( ; exerts influence on neural folds in developing embryo)

Question 27

elevating the palate and pharynx use what embryological structures?

Answer 27

branchial arches 1,3,4

Question 28

What embryologic origin gives rise to the superior parathyroid glands and ultimobranchial body, which forms the parafollicular C cells (adjacent to the thyroid follies)

Answer 28

4th pharyngeal pouch

Question 29

Meckel diverticulum is the MC congenital anomaly of the GI tract, it is a blind pouch protruding from the ileum, it is derived from ?

Answer 29

midgut

Question 30

What aortic arch gives rise to the common carotids as well as the proximal internal carotid arteries

Answer 30

third

Question 31

PDA is located in what arch?

Answer 31

sixth aortic arch

Question 32

Bell’s palsy is a lesion of CN 7, and affects the muscles of facial expression. What is the embryological origin of this nerve?

Answer 32

2nd branchial arch

Question 33

large cranium, small jaw, low set ears, and overlapping fingers

Answer 33

trisomy 18

Question 34

What teratogen is a/w fetal thrombocytopenia and jaundice?

Answer 34

chlorothiazide

Question 35

What teratogen is a/w permanent tooth staining, enamel hypoplasia, and diminished growth of long bones

Answer 35

doxycycline

Question 36

What teratogen is a/w fetal cardial abnromalities and malformations of the great vessels

Answer 36

lithium

Question 37

2 high risk consequences of coarctation of the aorta are?

Answer 37

bacterial endocarditis and cerebral hemorrhage