Hedera helix: Difference between revisions

''Hedera helix'' is able to climb relatively smooth vertical surfaces, creating a strong, long lasting adhesion with a force of around 300&nbsp;nN.<ref>{{Cite journal|last1=Xia|first1=Lijin|last2=Lenaghan|first2=Scott C.|last3=Zhang|first3=Mingjun|last4=Wu|first4=Yu|last5=Zhao|first5=Xiaopeng|last6=Burris|first6=Jason N.|last7=Stewart|first7=C. Neal|date=2011-03-01|title=Characterization of English ivy (Hedera helix) adhesion force and imaging using atomic force microscopy|journal=Journal of Nanoparticle Research|language=en|volume=13|issue=3|pages=1029–1037|doi=10.1007/s11051-010-0091-3|issn=1388-0764|citeseerx=10.1.1.495.3698|bibcode=2011JNR....13.1029X|s2cid=18080100}}</ref> This is accomplished through a complex method of attachment starting as [[adventitious root]]s growing along the stem make contact with the surface and extend root hairs that range from 20 to 400 μm in length. These tiny hairs grow into any small crevices available, secrete glue-like [[nanoparticle]]s, and [[lignification|lignify]]. As they dry out, the hairs shrink and curl, effectively pulling the root closer to the surface.<ref name="Melzer-2010">{{Cite journal|last1=Melzer|first1=Bjorn|first2=Tina |last2=Steinbrecher |first3=Robin |last3=Seidel |first4=Oliver |last4=Kraft |first5=Ruth |last5=Schwaiger |first6=Thomas |last6=Speck |date=12 May 2010|title=The attachment strategy of English Ivy: a complex mechanism acting on several hierarchical levels|journal=The Journal of the Royal Society Interface |volume=7 |issue=50 |pages=1383–1389 |language=en|doi=10.1098/rsif.2010.0140 |pmc=2894893 |pmid=20462880}}</ref>

The glue-like substance is a nano composite adhesive that consists of uniform spherical nanoparticles 50–80&nbsp;nm in diameter in a liquid polymer matrix. Chemical analyses of the nanoparticles detected only trace amounts of metals, once thought to be responsible for their high strength, indicating that they are largely organic. Recent work has shown that the nanoparticles are likely composed in large part of [[arabinogalactan]] proteins (AGPs), which exist in other plant adhesives as well.<ref name="Lenaghan-2013">{{Cite journal|last=Lenaghan|first=Scott|date=October 2013|title=Isolation and chemical analysis of nanoparticles from English ivy|journal=The Journal of the Royal Society Interface }}</ref>