Ch. 10,13,15

Question 1

Define degeneracy.

Answer 1

loss of original information

Question 2

Define metabolic dependency.

Answer 2

loss of metabolic capabilities

Question 3

________ parasitism may have ‘devolved’ by free-living, facultatively developing, arrested larvae becoming associated with animals, ultimately becoming parasites.

Answer 3

Trematode

Question 4

Define displacement.

Answer 4

no longer in original place and host association

Question 5

What is the life cycle of the black spot parasite?

Answer 5

1) Adult develops in the bird definitive host
2) Egg passes from kingfisher + hatches in water –> matures into miracidium
3) Miracidium penetrates snail
4) Sporocyst larval stage in snail
5) Sporocyst larval stage in snail develops into cercaria and emerges from snail
6) Cercaria penetrates fish + develops into metacercaria

Question 6

About how long is the trematode fluke cycle?

Answer 6

21 days

Question 7

What fluke life stages are found in snails?

Answer 7

Miracidium, Mother Sporocyst, Daughter Sporocyst, Cercaria

Question 8

What fluke life stages are found in fish?

Answer 8

Metacercaria

Question 9

what fluke life stages are found in the Kingfisher?

Answer 9

Adult Fluke

Question 10

What are the 4 major human organs in which trematode endoparasites can be found?

Answer 10

1) small intestine
2) liver
3) lungs
4) blood vessels

Question 11

What endoparasites are found in the small intestine?

Answer 11

1) Echinostoma spp.
2) Fasciolopsis buski

Question 12

What endoparasites are found in the liver?

Answer 12

1) Fasciola hepatica
2) Clonorchis & Opisthorchis spp.

Question 13

What endoparasites are found in the lungs?

Answer 13

Paragonimus spp.

Question 14

What endoparasites are found in the blood vessels?

Answer 14

Schistosoma spp.

Question 15

What is the reservoir host of trematodes?

Answer 15

bull looking animal

Question 16

what is the definitive host of trematodes (where sexual reproduction occurs)?

Answer 16

vertebrates (specifically humans)

Question 17

What is the first intermediate host of trematodes?

Answer 17

snail

Question 18

what is the second intermediate host of trematodes?

Answer 18

fish

Question 19

what is the infective stage of trematodes?

Answer 19

metacercaria

Question 20

Where does asexual reproduction of trematodes occur?

Answer 20

snails

Question 21

What are the characteristics of Class Cestoidea (tapeworms)?

Answer 21

1) segmented body
2) lack a digestive tract
3) heteroxenous life cycle

Question 22

What is the definitive host of tapeworms?

Answer 22

humans

Question 23

what stage and where in the human body are tapeworms found as the definitive host?

Answer 23

stage –> adult tapeworms
location –> small intestine

Question 24

what stage and where in the human body are tapeworms found as the intermediate/paratenic host?

Answer 24

stage –> larvae
location –> internal organs

Question 25

What is the intermediate/paratenic host of tapeworms?

Answer 25

humans

Question 26

What class of Platyhelminthes is mostly free living?

Answer 26

Class Turbellaria

Question 27

What are the general characteristics of Platyhelminthes?

Answer 27

1) flattened dorso-ventrally --> flatworms 2) acoelomates --> no body cavity + has parenchymal cells 3) Osmoregulation --> flame cell system 4) tegument (in parasitic) --> featureless 5) 2 types of reproductive systems --> monecious + dioecious 6) ovum (egg) --> contains first larva stage 7) miracidium --> develops within egg

Question 28

what are parenchymal cells?

Answer 28

packing tissue around organs

Question 29

What is the point of the flame cell system (osmoregulation)?

Answer 29

to remove water

Question 30

Describe monecious.

Answer 30

reproductive organs of male and female in one organism --> hermaphroditic

Question 31

Describe dioecious.

Answer 31

separate male and female worms

Question 32

What species is non-operculated?

Answer 32

schistosomes

Question 33

What are the characteristics of the miracidium life stage?

Answer 33

- hatches in water (or snail gut) - swims with ciliated - positive phototaxis (may have eyespots)

Question 34

How do you get swimmer's itch?

Answer 34

wading in infected waters

Question 35

About how many cases per year are there of swimmer's itch?

Answer 35

400,000

Question 36

What is the life cycle of the fluke in swimmer's itch?

Answer 36

1) eggs are passes in feces 2) eggs hatch + liberate miracidia 3) develops in a molluscan (snail) intermediate host 4) humans are exposed to the dermatitis-producing cercariae

Question 37

Who is the "father of tropical medicine" + discovered Schistosomes?

Answer 37

Manson

Question 38

what is the shape of most tapeworms?

Answer 38

leaf-like

Question 39

What are the drugs to treat flukes and tapeworms?

Answer 39

- Praziquantel - Oxamniquine, - Metrifonate - niclosamide

Question 40

what is protonephridia?

Answer 40

flame cell system

Question 41

what is an example of degeneration?

Answer 41

B12 deficiency from fish tapeworms

Question 42

Describe the differences between monogenea and digenea.

Answer 42

Digenea (flukes) : - complex life cycle involving multiple hosts - possess two suckers, one oral and one ventral, which they use to attach to their hosts Monogenea: - simpler parasites direct life cycle with only one host.

Question 43

Describe the differences between cestodes and trematodes?

Answer 43

Cestodes: - tapeworms - segmented plane - no digestive tract - hermaphrodites Trematodes: - flukes - unsegmented plane - incomplete digestive tract - hermaphrodites --> except schistosomas