What is the primary function of the macula densa?
1) Filtration of blood
2) Regulation of glomerular filtration rate
3) Secretion of renin
4) Reabsorption of glucose

In which brain regions are Broca's and Wernicke's areas located?
1) Inferior temporal gyrus and superior parietal gyrus
2) Inferior frontal gyrus and superior temporal gyrus
3) Superior frontal gyrus and middle temporal gyrus
4) Inferior parietal lobule and superior occipital gyrus

What is the main difference between endopeptidases and exopeptidases?
1) Endopeptidases cleave internal peptide bonds, while exopeptidases act on the terminal peptide bonds.
2) Endopeptidases are inactive in the stomach, whereas exopeptidases are active in the stomach.
3) Endopeptidases are exclusively found in the pancreas, whereas exopeptidases are exclusively found in the intestinal mucosa.
4) Endopeptidases are exclusively activated by enterokinase, whereas exopeptidases are activated by other enzymes.
E) Endopeptidases are inhibited by acidic pH, while exopeptidases function best at acidic pH.

Which of the following structures is associated with the control of voluntary eye movement?
1) Occipital lobe
2) Temporal lobe
3) Frontal eye field
4) Parietal lobe

What is the role of gastrin in the gastric phase of gastric acid secretion?
1) It directly stimulates the release of HCl from parietal cells.
2) It inhibits the release of HCl from parietal cells.
3) It activates the myenteric plexus to enhance intestinal motility.
4) It promotes the release of bicarbonate into the stomach lumen.
E) It is not involved in the gastric phase of acid secretion.