Parasitology. The Study of Parasites Morphology Classification Biology and physiology Parasite/Host interactions –Relationships –Reactions.

Presentation on theme: "Parasitology. The Study of Parasites Morphology Classification Biology and physiology Parasite/Host interactions –Relationships –Reactions."— Presentation transcript:

1 Parasitology

2 The Study of Parasites Morphology Classification Biology and physiology Parasite/Host interactions –Relationships –Reactions

3 What is a parasite? Type of symbiosis One species living at the expense of another species Host – both habitat and food Always does damage to host

4 Types of Symbiosis - Mutualism

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9 Giant Sequoia Seed Dispersal Mature cone producing plant ~100-150 years old Average cone is mature after 34 years Cones only release seeds when dry

10 Fire

11 Types of Symbiosis – Mutualism Long-horned wood-boring beetle

12 Types of Symbiosis - Mutualism Douglas squirrel

13 Types of Symbiosis - Commensalism

14 Terms to Describe Parasites Location on Host –Ectoparasite

15 Terms to Describe Parasites Location on Host –Endoparasite

16 Terms to Describe Parasites Time Spent on Host –Temporary – visit for food (tick) –Stationary Periodic – part of life cycle is parasitic (mermithid nematodes) Permanent – all stages are parasitic (cestodes)

17 Terms to Describe Parasites Incidental –Occasionally appear in unusual hosts –Example: Sheep liver fluke in dogs or cats Erratic or Aberrant –Occasionally found in unusual locations in the host –Example: Ascaris found in liver instead of intestine

18 Terms to Describe Parasites Obligate – must live as parasite Facultative – sometimes lives as parasite –Example: Blowfly

19 Adaptations Holding On! –Hooks, suckers, claws…

20 Adaptations Letting Go! –Natural outlets Alimentary canal, lungs, reproductive tract… –Example: Cestoda –Blood stream Blood sucking parasites –Example: Mosquitoes transmit plasmodium –Digestion by predators or scavengers

21 Taxonomic Tree of Animals

22 Parasitic Groups Viruses (not covered) Bacteria (not covered) Plants (not covered) Protozoans –flagellates –amoebae –sporozoans –ciliates Helminths –Flukes –Tapeworms –Roundworms –Spiny-headed worms Leeches Arthropods –crustaceans –lice –mites –ticks –mosquitoes –flies –fleas Vertebrates (not covered)

23 Microhabitats of Parasites Ectoparasites –hair/feathers –skin –mouth –gills

24 Microhabitats of Parasites Endoparasites (either intracellular or extracellular) –Intestine and liver –Heart, blood vessels and lymph nodes –lungs and air passages –kidney –muscles and connective tissue –central nervous system and sensory structures –reproductive structures

25 Adaptations to Microenvironments Ectoparasites Falling or being pulled off –Structures to hold on Example: tarsi of lice

26 Adaptations to Microenvironments Intestine Peristalsis –Structures to attach to intestinal lining Example: scolex of tapeworm

27 Adaptations to Microenvironments Intestine Digestive enzymes and acids –Resistant tegument Example: complex carbohydrate layer in tapeworms

28 Adaptations to Microenvironments Intestine Low oxygen environment –Anaerobic respiration –Unique biochemical pathways –Produces less ATP