Module 6: Communication

Plasma Membrane Receptors

Proteins that interact with ligands to alter the activity of cell proteins, playing important roles in cell communication.

Contact Signaling

Cell communication involving physical touch and recognition, important for development and immune responses.

Chemical Signaling

Interactions between receptors and ligands that lead to alterations in cell protein activity.

Cytokines

Communicating proteins that can act on a broad spectrum of target cells, involved in both direct and indirect cell communication.

Autocrine Signaling

A form of signaling where the cell acts on itself after releasing a signal. (Local)

Paracrine Signaling

Cell signaling that acts on nearby and adjacent cells. (Local)

Tonic Control Systems

A control system where the signal is always present, and the response is determined by signal frequency.

Antagonistic Control Systems

A control system involving two opposing signals where neither is turned off, with the levels dictating the response.

Local Controls (Intrinsic)

Responses to changes detected by a cell or tissue in its immediate vicinity. The tissue itself adjusts its activity based on its immediate needs

Reflex Controls (Extrinsic)

Responses coordinated outside of the stimulus area, involving afferent and efferent pathways. When organs are controlled by an outside system

Amplification of Signals

The process where a relative weak signal can result in a stronger intracellular message due to enzymatic activity.

Alpha Receptor

A receptor type that, when associated with epinephrine, causes vasoconstriction.

Beta Receptor

A receptor type that, when associated with epinephrine, causes vasodilation.

Efferent Pathway

Carries the response from an integrating center to target cells or tissues.

Integrating Center

The part of the nervous or endocrine system that receives information and initiates an appropriate response.

Reflux Steps

Stimulus→ Sensor→ Input Signal→ Integrating Center→ Output Signal→ Target→ Response→ Feedback Loop

Negative feedback loop

Counteracts a change, bringing a system back to stable equilibrium

Positive feedback loop

Amplifies a change in a system, pushing it further in the same direction

Hormone

(Endo) Chemical signal secreted into the blood and distributed all over the body by circulation

Neurohormone

(Nervous) Neurocrine molecule diffuses into the blood from body-wide distribution

Neurotransmitter

(Nervous) a neurocrine molecule defuses from the neuron across a narrow extracellular space to a target cell and rapid-onset effect

What are the types of chemical messengers(cytokines)?

Paracrine, autocrine, neurotransmitter, hormone, and Neurohormone