Cell communication and cycle vocab

Ligand

Signaling molecule

Neurotransmitter

Ligand used in nerve cell communication

Autocrine

Chemical signaling of a cell by itself

Paracrine

Chemical signaling between two nearby cells

Endocrine

Chemical signaling of two distant cells through the bloodstream

Juxtacrine

Chemical signaling of two touching or connected cells

Plasmodesmata

Channels that connect plant cells

Gap junctions

Spaces that in some cells that connect them to other cells and let small signaling molecules diffuse through

Reception

Receptor protein of the target cell receives the ligand

Signal transduction

Signal is passed through relay molecules

Response

Cell responds to the signal

Signaling cascade

Activation of a series of target proteins by relay proteins

Amplification

Increase in strength of a signal

Kinase

Enzyme type that adds phosphates to relay proteins, activating or (less frequently) inactivating them

Second messengers

Molecules in the cell that relay and amplify the signal

Gene expression

Process in which DNA is used to make proteins

Phenotype

Physical traits

Growth factors

Ligands that promote cell growth and division

Apoptosis

Programmed cell death

Homeostasis

Stable internal environment

Negative feedback

Bringing a too high level down or a too low level up (countering the stimulus)

Positive feedback

Maintaining and possibly accelerating the direction of the stimulus

Metabolic response

Enzymes become more or less active