Question

1. When fusion of the left and right mandibular prominences is incomplete, ____________ may result.

   		cleft philtrum
   		cleft palate
   		cleft chin
   		cleft lip

2 points   

QUESTION 21

1. You are a physician for a 15-year-old boy. The patient has a history of tonsil infections and is visiting your office today because he noticed mucus-like drainage collecting from a dimple-like spot on the left side of his neck. Remembering your embryology training, you examine the patient for a possible _______________ .

   		cervical vestige
   		cervical sinus
   		cervical fistula
   		cervical cyst

2 points   

QUESTION 22

1. Which of the following statements about circulation in a newborn baby is FALSE?

   		The foramen ovale closes because pressure is greater on the right side of the heart
   		Anatomical closure of the shunts takes longer than functional closure
   		The ductus venosus closes due to lack of blood flow from the placenta
   		The ductus arteriosus closes quickly after birth

2 points   

QUESTION 23

1. Which of the following migration movements must be disrupted to produce a pelvic kidney?

   		cranial migration
   		lateral migration
   		caudal migration
   		medial migration

2 points   

QUESTION 24

1. An infant is born two weeks premature.  The infant has trouble breathing normally immediately after birth. She takes short, shallow breaths, gasps for air and her fingertips appear blue. After 1 week of intensive care, corticosteroid treatment, and providing supplemental oxygen, she appears to have recovered completely. She is breathing normally. These symptoms were most likely caused by ___________________ .

   		tracheoesophageal fistula
   		alveolar capillary dysplasia
   		pulmonary hypoplasia
   		respiratory distress syndrome

2 points   

QUESTION 25

1. An individual carries XY chromosomes, but cannot respond to testosterone due to a mutation in the testosterone receptor. This individual will have ______________ .

   		normal testes
   		a normal uterus
   		normal ovaries
   		a normal p3nis

Answer 1

20- b

21- b

22- c

The ductus venosus is open at the time of birth and is the reason why umbilical vein catheterization works. The ductus venosus naturally closes during the first week of life in most full-term neonates; however, it may take much longer to close in pre-term neonates. Functional closure occurs within minutes of birth. Structural closure in term babies occurs within 3 to 7 days.After it closes, the remnant is known as ligamentum venosum.

23- a

After inducing the metanephric mesenchyme the lower portions of the nephric duct will migrate caudally (downward) and connect with the bladder, thereby forming the ureters. The ureters will carry urine from the kidneys to the bladder for excretion from the fetus into the amniotic sac. As the fetus develops, the torso elongates and the kidneys rotate and migrate upwards within the abdomen which causes the length of the ureters to increase

24- d .

it is a syndrome in premature infants caused by developmental insufficiency of pulmonary surfactant production and structural immaturity in the lungs

25- a

In this condition Physical examination revealed a 171 cm height, 55 kg weight patient with normal female external genitalia, normal breast development, but absence of pubic hair, and 4 cm deep blind-ending vagina. B-ultrasound showed one testicle located at right inguinal area accompanying right inguinal hernia, another testicle located in the left side of pelvic cavity, and without internal female genital organs (uterus and ovaries).