Biological Information Processing
Cells receive molecular signals, distinguish among them, integrate information, and produce coordinated responses.
The Investigative Question
In what sense do living systems process information?
What We Observe
Cells respond differently to nutrients, hormones, environmental signals, developmental cues, damage, and signals from neighboring cells.
Scientific Background
Signal-transduction networks use receptors, molecular switches, phosphorylation, second messengers, transcription factors, and other mechanisms to transmit and transform biological signals.
Why It Matters
Information-processing language can provide useful quantitative and conceptual tools for understanding how cells distinguish signals and coordinate responses.
What Is Known
Specific signaling pathways and regulatory networks have been characterized experimentally, and mathematical methods can measure aspects of signal transmission and cellular decision-making.
What Is Proposed
Systems biology models cellular signaling as interacting networks capable of filtering, amplification, integration, switching, and other forms of signal processing.
What Remains Uncertain
The word "information" is used in several different ways in biology. Care is needed when moving from measurable information in signaling or genetics to philosophical claims about information and design.
Design Relevance
Information processing is central to many Intelligent Design arguments. The investigation should distinguish measurable biological information processing from broader claims about the ultimate origin of biological information.
Assessment
Cells demonstrably transmit and process signals. Whether those processes provide evidence for design requires an additional argument concerning their origin and organization.