Which type of chemical signal is secreted from one cell and has effects on itself or its own type?

The correct choice, which identifies the type of chemical signal that is secreted from one cell and influences itself or its own kind, is autocrine signaling. In this type of signaling, a cell produces signaling molecules that bind to receptors on its own surface or on cells of the same type, leading to effects such as growth, differentiation, or other cellular responses. Autocrine signals enable cells to regulate their own functions and behaviors, making them crucial for processes like immune responses and the regulation of cell growth.

Neurotransmitters, while crucial for communication between neurons, act specifically on neighboring (post-synaptic) cells and do not typically function in the autocrine manner. Pheromones are chemical signals released into the environment that affect other individuals of the same species, playing a key role in communication and behavior, rather than self-communication. Paracrine signals refer to substances that are secreted by cells and act on nearby target cells, rather than the originating cell itself, distinguishing them from autocrine signals which have localized effects on the secreting cell.