Exam 2: Physiology of Cells and Molecules

Two people have the same total body mass (70 kg) but one has a much higher percentage of body fat than the other. They both habitually ingest 2.5 L of water per day. The individual with the higher percentage of fat will have a:

A 1-day-old neonate with acute respiratory distress syndrome (ARDS) has moderately severe hypoxemia. Physical examination reveals, dry inspiratory crackles in the lungs and a continuous harsh murmur heard over the entire precordium. Which of the following sets of oxygen saturation (SaO₂) values in the cardiac chambers and vessels most likely match those of this patient? Right atrium (RA) Normal (\%) Right ventricle (RV) 75 Pulmonary artery (PA) 75 Pulmonary veir (PV) 75 Left ventricle (LV) 95 Aorta () 95 RA RV PA PV LV A (\%) (\%) (\%) (\%) (\%) (\%) A 75 80 80 95 95 95 B 80 80 80 95 95 95 C 75 75 80 95 95 95 D 75 75 75 95 80 80 E 75 75 75 95 95 95

A 30-year-old woman in her first trimester of pregnancy complains of easy fatigability, heat intolerance, and palpitations. Physical examination shows a slightly enlarged, nontender thyroid gland. Thyroid function studies show an increased total serum thyroxine (T₄) level, but normal serum thyroid-stimulating hormone (TSH) levels. Which of the following best explains the results of these studies?

Which of the following statements best describes ARDS (acute respiratory distress syndrome)?

Suppose the plasma membrane of a particular mammalian cell is much more permeable to water and urea than to any other solute. The water permeability is higher than the urea permeability. The cell is initially in a normal physiological saline solution and then is suddenly moved into a solution consisting of 600 mM urea as the only solute. The cell will:

A 56-year-old right-handed woman states that her right hand shakes when she tries to open a door. Her physician does not observe a tremor when the patient's hands are resting in her lap. She further states that she falls frequently, usually to the right side. The most likely cause of these findings is a lesion in the:

A 60-year-old man comes to your office complaining of dyspnea (difficult breathing). His laboratory values are as follows: Breathing Breathing 100 \% air for 7 minutes Arterial () 76 500 Arterial () 55 65 Arterial (/100) 18 18 Arterial saturation (\%) 85 100 Arterial 7.35 7.20 Which of the following diagnoses best explains the laboratory test findings?

A 50-year-old homeless man with a 30-year history of alcoholism complains of painful lesions on the mucous membranes of his mouth and tongue and has pigmented keratotic scaling lesions on his face and hands. In addition, he is weak, forgetful, and has burning sensations in various parts of the body and diarrhea. A deficiency of which of the following is most likely to account for these findings?

If a healthy 70 kg man loses 2 L of sweat while doing yard work and simultaneously drinks 2 L of pure water, which of the following body fluid changes would be expected?

Which of the following is correct for male sex differentiation?