A 49-year-old woman visits her physician because of vision problems. She works the night
shift as a security guard at an oil mining outpost. Recently she says the day seems to get
darker faster and everything seems a lot more dim around her at work. Her past medical
history is significant for hyperthyroidism treated with radioactive iodine. Physical examination
shows yellow skin. Pupils are equal, round, and reactive to light. What is the most likely
cause of her symptoms?
- A. Liver cirrhosis
- B. Pancreatic tumor of the head
- C. Excessive breakdown of heme
- D. Decreased absorption of β-carotene
- E. Decreased conversion of β-carotene to vitamin A
0 voters
A young healthy couple arrives at the clinic for genetic counseling because the man has a
family history of miscarriages. A cytogenetic analysis of the man’s karyotype shows a
translocation between chromosome 4 and 6 [46,XY,t(4;6)(q21;q14)]. He does not have any
physical or mental abnormalities. Karyotype analysis of the woman shows no abnormalities.
If the couple were to have a child, what are the chances the baby will be phenotypically
normal?
- A. 20%
- B. 25%
- C. 33%
- D. 50%
- E. 75%
0 voters
A 15-week-old boy was brought to the physician by his mother because of cough, fever,
chills, and shortness of breath. Physical examination shows white plaques on the tongue that
can be scraped away. A chest x-ray shows pneumonitis. Lab testing reveals low serum IgG.
An inquiry into family history uncovers the following pedigree.
The physician tells the mother that the incidence of this disease is 1/50,000. How many
people in the general population are carriers of this disease?
- A. 1/1,000
- B. 1/20,000
- C. 1/25,000
- D. 1/50,000
- E. 1/100,000
0 voters