Extracellular signaling molecules of plants that exert their effects on target cells at very low concentrations are called ____.

A) hormones
B) peptide
C) sugars
D) starches
E) lipids

Extracellular

Located or occurring outside a cell or cells, often referring to substances or fluids in the spaces between cells.

Signaling Molecules

Chemicals that are involved in transmitting information between cells, allowing for processes such as growth, immune response, and neurotransmission.

Hormones

Chemical substances produced in the body that regulate and control the activity of certain cells or organs.