Final answer:
Hormones are chemical messengers that are secreted into the bloodstream by endocrine glands and affect cells throughout the body.
Neurotransmitters, on the other hand, are chemical substances that transmit electrical signals across synapses between neurons.
Step-by-step explanation:
The correct answer is C. Hormones are chemical messengers, but neurotransmitters are electrical signals. Hormones and neurotransmitters are both involved in cell communication, but they differ in their mode of action.
Hormones are chemical messengers that are secreted into the bloodstream by endocrine glands and travel throughout the body to affect cells that have specific receptors for them.
On the other hand, neurotransmitters are chemical substances that diffuse across synapses between neurons to transmit electrical signals from one neuron to another. Therefore, the main difference between hormones and neurotransmitters is their signaling mechanism.