This document discusses different types of pheromones in insects, including sex pheromones released by female insects to attract males for reproduction, alarm pheromones that alert others of danger, and aggregation pheromones that promote group behaviors. It also mentions how hormones in humans like insulin, thyroxin, gastrin, and prolactin are released by exocrine glands to regulate metabolic processes, whereas pheromones in insects are released by similar exocrine glands but function for communication between individuals.