Key Points
Key Points
- Cell signalling is vital for all cells to be able to interact with their environment. Cells are able to receive external stimuli, internalise the information and create change within the cell in response to the stimulus. Cell signalling allows coordinated functionality that is imperative for development of multicellular organisms.
- Cells can also coordinate their responses, allowing a community of cells to competitively survive. Some forms of bacteria can form communities known as biofilms. These biofilms are a complex microbial community composed of one or more types of bacteria that influence the actions of neighbouring cells and preventing growth of competing cells that could negatively affect the health or development of the microbiome. These communities are imperative for human health, such as the communities found within the gastrointestinal tract that aid in digestion but can also be harmful to health such as those found in the plaque on teeth (as the bacteria can produce metabolites that destroy teeth enamel).
- Cell signalling can target nearby cells (paracrine), target distant cells (endocrine), target the same cell that releases signalling molecules (autocrine) or target connected cells via gap junctions.
- There are three basic types of connections for epithelial cells. Gap junctions allow small molecules to move via channels connecting two neighbouring cells together. Tight junctions attach apical and basal cells together. Anchoring junctions stabilise epithelial tissues and include adherent junctions, desmosomes and hemidesmosomes that are responsible for attaching cells together at different points of the cell.
