Holdfast (biology), Holdfast
Holdfast most often refers to: *Holdfast (biology), a root-like structure that anchors aquatic sessile organisms to their substrate *Holdfast (tool), a tool used to secure a workpiece to a workbench or anvil Holdfast or hold fast may also refer to: Places * Holdfast, Worcestershire, a village in the Malvern Hills District in England * Holdfast, Saskatchewan, a village in Canada Arts and entertainment Music * Hold Fast (album), ''Hold Fast'' (album), a 2012 album, or the title song, by the Crookes * ''Hold Fast: Acoustic Sessions'', a 2018 album by Face to Face * ''Hold Fast'', a 2020 album by Stick in the Wheel * Hold Fast (song), "Hold Fast" (song), a 2006 song by MercyMe * "Hold Fast", a 2010 song by Honor Bright from ''Action! Drama! Suspense!'' Other media * ''Hold Fast'', a travel documentary film by Moxie Marlinspike * ''Holdfast: Nations at War'', a video game set during the Napoleonic Wars; see Napoleonic Wars in fiction Other uses * Hold Fast, the motto of the Clan Ma ...
[...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  

Holdfast (biology)
A holdfast is a root-like structure that anchors aquatic sessile organisms, such as seaweed, other sessile algae, stalked crinoids, benthic cnidarians, and sponges, to the substrate. Holdfasts vary in shape and form depending on both the species and the substrate type. The holdfasts of organisms that live in muddy substrates often have complex tangles of root-like growths. These projections are called haptera and similar structures of the same name are found on lichens. The holdfasts of organisms that live in sandy substrates are bulb-like and very flexible, such as those of sea pens, thus permitting the organism to pull the entire body into the substrate when the holdfast is contracted. The holdfasts of organisms that live on smooth surfaces (such as the surface of a boulder) have flattened bases which adhere to the surface. The organism derives no nutrition from this intimate contact with the substrate, as the process of liberating nutrients from the substrate requires ...
[...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]