Biologists Schleiden and Schwann would state that

The nervous system interacts with the endocrine system by a. using hormones as connections b. sending nerve impulses directly to glands c. using neuroendocrine cells as connections d. sending neurotransmitters directly to neurons

Which best describes the scientific method? a. a path of clearly defined steps that must be followed in a particular order b. a possible answer to a scientific question based on knowledge or research c. the recipe for how to conduct an experiment that must be followed precisely d. the process of hypothesis and testing through which scientific inquiry occurs

What type of appendages do sponges cnidarians roundworms annelids mollusks arthropods echinoderms and vertebrate have? jointed, not jointed, absent