There are four basic categories of chemical signaling found in multicellular organisms: paracrine signaling, autocrine signaling, endocrine signaling, and signaling by direct contact.

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In this section, we’ll look at different types of receptors and ligands, seeing how they interact to turn information from outside the cell into a change inside the cell.

The many different ways cells can change their behavior in response to a signal.

Unit 9: Cell signaling About this unit This unit is part of the Biology archive. Browse videos and articles by topic. For our most up-to-date, mastery-enabled courses, check out High School …

How single-celled organisms use signals to communicate. Yeast mating types, bacterial quorum sensing, and biofilms.

Direct contact involves gap junctions or complementary surface proteins. Paracrine communication happens over short distances, while endocrine signaling involves hormones …

Learn how signals are relayed inside a cell starting from the cell membrane receptor. The chains of molecules that relay intracellular signals are known as intracellular signal transduction …

Despite these differences, signaling pathways share a common goal: to produce some kind of cellular response. That is, a signal is released by the sending cell in order to make the …

Cell communication is crucial for complex organisms. Cells can communicate directly through contact or indirectly via chemical signaling. This communication can occur over short …