Q- A patient presents with end-stage chronic renal disease. Which of the following substances is most likely increased in blood value in this patient?
A- Calcium
B- Erythropoietin
C- Hematocrit
D- Phosphate
D- Phosphate- Phosphate excretion is reduced in chronic renal failure leading to its accumulation in the blood which results in low blood calcium. Erythropoietin will decrease due to kidney failure to produce it and hematocrit will be reduced as a result of it.
Q- Calcitonin acts on which one of the following cell types to decrease serum calcium and bone resorbing activity?
A- Osteoblast
B- Osteoclast
C- Osteocyte
D- Osteon
B- Osteoclast- Calcitonin reduces the activity of osteoclasts by reduction of their surface ruffling. Osteoblast and osteocyte are bone-forming cells. Osteon is the chief structural unit of compact bone.
Q- A college student complains of a recent yellow discoloration of her eyes. She has no change in her stool and she does not drink any alcohols. Her liver enzymes and direct bilirubin are normal while total bilirubin is high. Which of the following is the most likely cause of her jaundice?
A- Alcoholic liver
B- Hemolysis
C- Hepatoma
D- Liver congestion
B- Hemolysis- Destruction of RBCs can lead to high level of indirect bilirubin and jaundice. Liver will not be able to conjugate this large amount of bilirubin leading to accumulation of indirect (unconjugated) bilirubin in the blood. Liver pathology will result in high level of direct (conjugated) bilirubin.
