Which of the following cranial nerves plays an important role in regulating the heartbeat?

Which of the following secretions causes a decrease in blood pressure?

Which of the following hormones is secreted by the kidney?

Identify the wrong statements:
$A.$ Erythropoietin is produced by juxtaglomerular cells of the kidney.
$B.$ Leydig cells produce Androgens.
$C.$ Atrial Natriuretic factor,a peptide hormone,is secreted by the seminiferous tubules of the testes.
$D.$ Cholecystokinin is produced by the gastro-intestinal tract.
$E.$ Gastrin acts on the gastric glands and stimulates the secretion of hydrochloric acid and pepsinogen.
Choose the most appropriate answer from the options given below:

Select the correct set of hormones of the gastrointestinal tract:

Which of the following structures does not contribute to the secretion of hormones?