17/05/2018: Today in strucTEM microscopes: The tick and its tools

Ticks are bloodsucking mites. Many of them are carriers of disease.
We took a closer look at the tools ticks use to get our blood.

How does the tick find us? )
In the last leg segment of the first leg pair (4) there is a pit, the Hall organ (e). It contains chemoreceptors that enable the tick to find the host.

At the end of each leg (4,5) - it has 8 of them - are the claws with two claws each (d). With these claws the tick can hold on to itself

How does the tick get our blood? )
Next to the head there are 2 buttons, the palps (a). Once she has found the right place to prick, she uses 2 knives, the Cheliceren(c)to scratch our skin. It is then inserted into the wound with the dowel-like hypostome (b). The blood exuding from the wound then licks them up.

The tick from picture 1 crawled around on the microscopist. We had her in the microscope. Nice to see is the mouthpiece with an intact hypostome.
In the 2nd tick (picture 2) there are still remains of skin on the hypostome: it had stung the microscopist and came straight into the scanning electron microscope for punishment.
The same thing happened to the tick in Fig. 3, but the microscopist was unlucky: the hypostome broke off (b) and got stuck in the skin. The view is clear on the small knives/chelicers (c)

Ticks in scanning electron microscope © strucTEM 2018

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