Platyhelminthes

Question 1

While most of the platyhelminthes are free living or endoparasites, Give an example of a taxa that has an ectoparasitic life cycle

Answer 1

Monogenea

Question 2

Cells that secrete mucus in the epidermis of the Turbellaria are called

Answer 2

Rhabdites

Question 3

Protonephridia function in
A) 	waste disposal.
B) 	respiration.
C) 	osmoregulation.
D) 	digestion.

Answer 3

A) Waste disposal

Question 4

Which of the following groups includes ectoparasites of fish and amphibians?
 A) 	Monogenea
 B) 	Turbellaria
 C) 	Trematoda
 D) 	Cestoda

Answer 4

A) Monogenea

Question 5

Cestodes are monoecious and lack a digestive tract. The reproductive units of the cestodes are called

Answer 5

Proglottids

Question 6

In the digenetic trematodes, the first or invertebrate host is called the _________ and the second or final host, which is usually a vertebrate, is called the _________ host.

Answer 6

Intermediate, definitive

Question 7

What is the phylogentic tree of platyhelminths?

Answer 7

True tissue -> Bilaterally symmetrical -> Protostome -> Lophotrochozoa (Or trochopore larvae) -> absent unsegmented coelom

Question 8

What are the general Environment characteristics

Answer 8

Marine, Freshwater, Moist terrestrial, some times parasitic

Question 9

What are the general Development characteristics

Answer 9

Acoelomate, Triploblastic, Bilaterally symmetrical, Dorsoventrally flattened.

Question 10

What are the general Reproduction characteristics

Answer 10

Hermaphroditic, internal/cross fertilisation

Question 11

What are the general Digestion characteristics

Answer 11

Single opening to the gut, or no gut.
Lateral canals with flame cells - Excretory system.
Diffusion across the body surface

Question 12

What are the general Sensory characteristics

Answer 12

Paired anterior ganglia. Longitudinal nerve cord

Question 13

What are the general Respiratory characteristics

Answer 13

No specialised respiratory circulatory systems.

Question 14

What are the 4 major classes?

Answer 14

Turellaria (Free-living flatworms)
Cestoda (Tapeworms)
Monogenea (Ectoparasite)
Trematoda (Flukes)

Question 15

What are the general characteristics of the class Turbellaria

Answer 15

Aquatic (Some terrestrial)
Free-living (Some parasitic)
Moves via a mucous layer (Adhesive/releaser glands) also with a ventral cilia
Acoels(Poorly formed gut/Elaborately branched)
Sexual/asexual

Question 16

What are the general characteristics of the class Cestoda

Answer 16

Endoparasitic,
Has Scolex (Hooks/suckers for attachment)
Diffusion for nutrients.
No mouth or gut
Reproduction via Prolottid (Segment containing reproductive organs/fertilised eggs)

Question 17

What is the reproduction cycle of a Cestoda

Answer 17

Prolottid breaks of adult form -> Leaves host via fecal matter -> eggs consumed via intermediate host (May enter more than one intermediate host) -> Enters definitive host -> Sexually matures -> Repeat cycle.

Question 18

What is the Oncosphere stage of a Cestoda

Answer 18

A 3 paired hooked larvae stage

Question 19

What are the general characteristics of the class Monogenea

Answer 19

Ectoparasite on fish
Life-cycle Adult produces eggs -> eggs hatch into Oncomiracidium (Larvae stage) -> Attach to new host -> Sexually mature -> Repeat

Question 20

What are the main requirements of the parasitic life styles of this phyla

Answer 20

Reproduction (Getting the eggs out of host)
Locate (Detection of a host/entering the host)
Maintain position (Remaining in the ideal spot within a host)
Lack of O2 (The use of diffusion)
Defending from the host (Hiding in cells/Changing chemicals, ect)

Question 21

Briefly describe the life cycle of a Opisthorcis sinensis (Human liver fluke)

Answer 21

Infected raw fish eaten by human -> Sinensis enters, develops to sexually maturity -> Miracidium released via faeces -> snail intermediate host -> develop into rediae -> Multiple cercariae leave snail -> Free-swimming, find host fish gills -> fish muscles then metacercarial cysts -> Repeat