Thesis-PDF - IAP/TU Wien

Figure 4.17: (Image reproduced from chapter 6, Results) Pellicular strips
of an E. gracilis cell showing ridges, mucilage (arrows) excreted at canal
openings between the strips and a bundle of three microtubuli (arrowheads)
presumably stemming from a disrupted cell. Image size 1 µm 2 , Intermittent
contact mode AFM image, Amplitude trace.
thus forming a weak gel. 13 . Some organisms such as limpets are also known to
further crosslink and modify this network of proteins, raising its viscosity or giving
it adhesive properties. ([106], [107])
In conclusion, a number of essential parts make up the pellicle and provide
it with the ability to actively alter its shape. The pellicle strips are allowed a
certain amount of relative sideways movement, accomplished by the ridge sliding
in the groove together with compression and stretching of the pellicular material.
Microtubuli, arranged parallel to each pellicular strip and varying in numbers and
distributions in different species, motor these movements. Additionally, mucilage
producing bodies reduce friction and protect the articulations of the pellicle from
wear.
13 In mammals, lubricating mucous gels line and protect the digestive, reproductive, and respiratory
tracts. In marine invertebrates, mucus typically forms a slippery coating that prevents
bacteria and debris from accumulating on the body surface and keeps other organisms from
adhering to it.
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