Cell Communication

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Cell Communication

The process by which a cell senses its environment and communicates with other cells.

Prokaryotes

Single-celled organisms that lack a membrane-bound nucleus.

Eukaryotes

Organisms whose cells have a nucleus enclosed within membranes.

Unicellular organisms

Organisms composed of a single cell.

Multicellular organisms

Organisms composed of multiple cells.

Contact-dependent signaling

A form of signaling where one cell directly contacts another cell.

Signaling molecules

Molecules such as hormones, ions, or small organic molecules used in intercellular communication.

Autocrine signaling

A type of signaling where a cell stimulates itself.

Paracrine signaling

Signaling between nearby cells.

Hormone signaling

Also known as endocrine signaling, involves molecules that travel long distances.

First messenger

The signaling cell or environment that initiates cell communication.

Ligand

The general name for signaling molecules.

Receptor protein

A protein that binds to a signaling molecule.

Transmembrane protein

Membrane proteins that interact with ligands on the extracellular surface of the cell membrane.

Cytoplasmic proteins

Proteins located inside the cell that may act as receptors for non-polar ligands.

Steroid hormone

A type of hormone that is lipid-soluble and can pass through cell membranes.

Target cell

A cell that has a receptor for a specific ligand.

Non-covalent interactions

Interactions such as hydrophobic, ionic, and van der Waals forces involved in receptor-ligand binding.

G protein-coupled receptor

A type of receptor that activates a G protein upon ligand binding.

Receptor kinase

A receptor that acts as an enzyme to phosphorylate itself upon activation.

Self-phosphorylation

A process where a receptor adds phosphate groups to itself using ATP.

Ligand-gated ion channel

A receptor that opens a channel in response to ligand binding.

Signal transduction

The process of transmitting receptor activation into the cell.

Phosphorylation

The addition of phosphate groups to proteins, often activating them.

Second messengers

Molecules such as cyclic AMP (cAMP) produced inside the cell that transmit signals.

Calcium ions (Ca2+)

Important signaling molecules involved in various cellular responses.

Apoptosis

Programmed cell death that is a regulated process.

Termination of response

The process by which a cell stops responding to a signal.

Receptor specificity

The concept that a cell’s response to a signal is determined by the presence of specific receptors.

Signal amplification

The enhancement of a signal through a chain reaction of events within the cell.

Gene expression change

Alterations in the transcription of genes leading to changes in protein synthesis.

Exocytosis

The process by which a cell secretes materials to the outside.

Metabolic pathway change

Alterations in the series of chemical reactions within a cell based on signaling.

Ion flow

The movement of ions across plasma membranes often mediated by channels.

Programmed cell death

A controlled process by which cells undergo death, also known as apoptosis.

Environmental signals

Signals from the environment that affect cellular function.

Long distance signaling

Signaling pathways that involve communication over greater distances, often hormonal.

Short distance signaling

Signaling pathways that occur via diffusion over a small range.

Membrane proteins

Proteins that are integral or peripheral to the cell membrane involved in signaling.

Cytosolic surface

The inner surface of a cell membrane where intracellular proteins may interact with receptors.

Hydrophobic interactions

Interactions that occur between non-polar parts of molecules, important in receptor-ligand binding.

Ionic interactions

Attractions between oppositely charged ions, contributing to molecular interactions in signaling.

Vascular tissue

Plant tissue that facilitates the transport of hormones within the plant.

Cellular diversity

The concept that different cell types respond differently to the same signaling molecules.