Adhesins are cell-surface components or appendages of bacteria that facilitate adhesion or adherence to other cells or to surfaces, usually in the host they are infecting or living in. Adhesins are a type of virulence factor.
drae adhesin from escherichia coli
Adhesion is the tendency of dissimilar particles or surfaces to cling to one another.
Dew drops adhering to a spider web
Concave meniscus is caused due to adhesion.
Diagram of various cases of cleavage, with each unique species labeled. A: γ = (1/2)W11 B: W12 = γ1 + γ2 – γ12 C: γ12 = (1/2)W121 = (1/2)W212 D: W12 + W33 – W13 – W23 = W132.
Cohesion causes water to form drops, surface tension causes them to be nearly spherical, and adhesion keeps the drops in place.