AP Biology Chapter 5: Cell Communications - Majoros

signal transduction pathway

process where surface cellular responses cause responses within the cell

local regulator

a released, short-distance signaling molecule which travels between the secreting and target cell

hormone

a released, long-distance signaling molecule which travels between the secreting cell (endocrine) and the target cell

ligand

a signaling molecule

G protein-coupled receptors

uses a signaling molecule/ligand, a G protein/GTPase and GTP to activate an inactive enzyme; located in a membrane

G proteins

relays signals from a plasma membrane signal receptor, known as a G protein-coupled receptor, to other signal transduction proteins in the cell

receptor tyrosine kinases

molecules activated by ligands and phosphates to activate a response

ligand gated ion channel receptors

block and allow ions in and out of the cell

protein kinase

general name for an enzyme that transfers phosphate groups from ATP to a protein

protein phosphatases

(PP) enzymes that rapidly remove phosphate groups from proteins during signal transduction

second messengers

small, non-protein, water-soluble molecules/ions that act as the signaling molecule/ligand

cyclic AMP (cAMP)

an important second messenger that helps make protein kinase A (PKA); made with help of the signaling molecule epinephrine

adenylyl cyclase

an enzyme that converts ATP to cAMP

apoptosis

cellular suicide

growth factors

compounds that stimulate nearby target cells to grow and divide

paracrine signaling

a type of local signaling where the target cell is close to the signal-releasing cell

synaptic signaling

a type of local signaling specific to neurotransmitters in nerve cells

hormonal signaling

a type of long-distance signaling where an endocrine excretes hormones in a blood vessel to travel to a target cell

reception

when a signaling molecule binds to a receptor protein

Biomily

The people you can depend on and the people that depend on you.

response

when an enzyme is activated to do an activity in a cell

transcription factors

control which genes are written (transcribed) onto mRNA at a certain place and at a certain time

GTP

moves proteins around for cellular response, (like rage)

phosphorylation cascade

a chain reaction of chemical reactions where an enzyme adds a phosphate group to a series of proteins, activating each one in sequence.