After leaving the epididymis, seminal fluid enters which of the following areas?

A. The thyroid gland functions only as an endocrine gland. It secretes hormones like thyroxine (T4) and triiodothyronine (T3) into the bloodstream, but it does not have an exocrine function.

B. The pituitary gland is an endocrine gland that secretes hormones into the bloodstream but does not have exocrine functions.

C. The hypothalamus is involved in hormone production and regulation but is considered part of the brain rather than an endocrine or exocrine gland itself.

D. The pancreas functions as both an endocrine and exocrine gland. It produces insulin and glucagon (endocrine functions) and secretes digestive enzymes into the small intestine through ducts (exocrine function).

A. Calcium plays a critical role in blood clotting. It is involved in the coagulation cascade and is necessary for the activation of clotting factors that help stop bleeding.

B. Calcium is not involved in acid buffering. This function is primarily carried out by buffers such as bicarbonate in the blood.

C. While calcium does help regulate some functions of cells and tissues, it does not primarily contribute to extracellular osmotic pressure; this is more a function of proteins and other ions.

D. ATP production mainly occurs in mitochondria and is driven by the metabolism of glucose and fatty acids, not by calcium directly. Calcium does, however, play a role in cellular processes like muscle contraction.