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==Morphology==
==Morphology==
*Mouthparts
**Sensory organs for locating a feeding site called '''palps'''
**Chelicerae for puncturing the skin
**The '''hypostome''' pushes through the wound made by the chelicerae where backwards pointing teeth lock the mouthparts into the skin
***Dorsal groove in the hypostome permits the flow of tick saliva and host blood
===Hard Ticks===
*Hard, chitinous covering over dorsal surface called the '''scutum'''
**Unique to hard ticks
**Males have a scutum which covers the entire body surface
**Females have a scutum which only covers a small area behind the head
*Prominant biting mouthparts
*Festoons ('pie crust edging') around the posterior body margins
*Enamel coloured patches on scutum are present on '''ornate ticks'''
*Female hard ticks may swell up to three times their normal size when taking a blood meal
===Soft Ticks===
*No scutum
*Mouthparts are not visible from dorsal surface
*Feed little and often as cannot swell as much as hard ticks
==Feeding==
*Ticks stand upright
*Chelicerae cut through skin creating a pool of blood
*Hypostome is inserted deep into the skin
*Mouthparts are cemented into place
*Ticks feed continuously
*Tick saliva flows into host
**Histamine blocking agents to minismise the host inflammatory response
**Anticoagulents to ensure the free flow of blood
**Cytolysins to enlarge the feeding lesion
**Vasoactive mediators, enterases and carbohydrate splitting enzymes to increase the vascular permeability, facilitating feeding
**Paralytic toxins
*Host tissue is broken down leaving a zone of necrosis creating a '''feeding lesion'''
==Life Cycle==
==Life Cycle==