AP Bio. Cell Communication

Cell Communication

The process that enables cells to communicate with each other through various signaling methods.

Direct Communication

A type of cell communication where substances pass freely through cytoplasm to adjacent cells, example by immune cells

What type of direct communication is used in animals?

Gap junctions

What type of direct communication is used in plants?

Plasmodesmata

Local Signaling

Cell communication through secreted messages over a short distance, including examples like synaptic signaling (neurotransmitters) and paracrine signaling (local regulators).

Long Distance Signaling

A type of signaling where hormones are used to communicate over longer distances, as seen in insulin signaling in animals and hormone transport in plants through vascular tissues.

Stages of Cell Signaling

The three stages are reception, transduction, and response.

Reception

The initial stage of cell signaling where a ligand binds to a specific receptor, leading to transduction.

Transduction

The second stage of cell signaling, converting an extracellular signal to an intracellular signal to elicit a cellular response.

Response

The final stage of signaling where the influence of the signal leads to a change in cellular processes.

Kinase

An enzyme that adds a phosphate from ATP to relay the signal inside the cell.

Phosphatase

An enzyme that removes a phosphate to deactivate a signaling pathway.

Second Messengers

Small, non-protein molecules and ions like cyclic AMP that relay and amplify signaling responses during transduction.

G-Protein Coupled Receptors (GPCRs)

The largest category of cell surface receptors important in sensory systems, involving G proteins that activate upon ligand binding.

Ligand-Gated Ion Channels

Receptors that act as gates for ions in the plasma membrane, opening or closing upon ligand binding to allow ion diffusion.

Paracrine Signaling

A type of cell communication involving the secretion of substances to adjacent target cells.

Plasmodesmata

Structures that allow plant cells in direct contact to diffuse substances for communication.

Ligand

A macromolecule that binds to a specific signal molecule in reception.

Defective Protein Phosphatase

A malfunctioning enzyme that would prevent signal transduction pathways from shutting off, resulting in an overproduction of molecules.

What are some examples of responses a cell can do?

change in membrane permeability, change metabolic process, and proteins that turns genes on or off

What is an affect of mutations?

Change in phenotype or cell death

What happens to the GDP when the ligand binds to the GPCR?

It goes from GDP to GTP

What happens once the G protein binds to the GPCR?

Part of the G protein and the GTP binds to the inactive enzyme and amplifies signal and gets a cellular response.

What type of cell membrane receptor is important in the sensory systems?

GPCR’s

What type of cell membrane receptor is important in the nervous systems?

Ion Channels