Hormones
A) cannot affect the cells secreting the hormones.
B) can be secreted by individual cells, such as those lining portions of the digestive tract.
C) are secreted by exocrine glands, such as the exocrine portion of the pancreas.
D) cannot pass through cell membranes after they have been secreted.
E) are released from hormone-producing cells by endocytosis.

Question

Quizplus · Accepted Answer

Hormones can be secreted by individual cells, such as those lining portions of the digestive tract. These cells are known as enteroendocrine cells and they secrete hormones such as gastrin and secretin.

Answer: D
 Most hormones cannot pass through cell membranes after they have been secreted because they are typically large, complex molecules. Instead, they must bind to receptors on the surface of target cells to initiate a response.