Day 12: Tapeworm Morphology and Biology

Question 1

What general shape are tapeworms

Answer 1

Dorsoventrally flattened

Question 2

What are the two main parts of a tapeworm

Answer 2

Scolex
Strobila

Question 3

What is the scolex

Answer 3

Contains attachment apparatus (suckers, rostellum with hooks)

Question 4

What is the strobila

Answer 4

Contains immature, mature and gravid proglottids
Proglottids are more mature as you progress down the length of the worm

Question 5

What is the tapeworm’s reproduction

Answer 5

They are hermaphroditic
Made up of proglottids
Each proglottid has both sets of sex organs
Self-fertilize
Identify species based on characteristics of the proglottids

Question 6

How many gential pores does Diplylidium have

Answer 6

2

Question 7

how many genital pores does Taenia proglottid have

Answer 7

1

Question 8

Where do all tapeworms live

Answer 8

GI tract and associated ducts

Question 9

What do cestodes not have

Answer 9

GI tract
Mouth
Gut
Anus

Question 10

What is a microthrix

Answer 10

Surface is a syncytial epithelium with microthrix
nutrients absorbed across this and waste products are released
Has projections that hook onto the host epithelium to maintain the worm’s place in the gut

Question 11

What are the intermediate stages called

Answer 11

Cyclophyllidean

Question 12

How many intermediate stages are present

Answer 12

5

Question 13

Name the 5 intermedate stages

Answer 13

Cysticercoid
Cysticercus
Coenurus
Strobilocercus
Hydatid

Question 14

Describe Cysticercoid

Answer 14

Exists in arthropod vectors like fleas, contains an inverted scolex in a solid matrix

Question 15

Describe Cysticercus

Answer 15

Tiny fluid-filled bladder containing a single inverted scolex

Question 16

Describe Coenurus

Answer 16

Fluid-filled bladder containing many inverted protoscolices (each scolex can develop into an individual adult)

Question 17

Describe Strobilocercus

Answer 17

Scolex with segmented “neck” connected to a fluid-filled bladder
After ingestion by the definitive host, all but then scolex and some germinative tissue is digested

Question 18

Describe hydatid

Answer 18

Large fluid-filled structure similar to a coenurus that has “daughter” cysts that bud into the middle of the “mother” cyst to increase surface area