Cestodes (generalities + characs) Flashcards
The cestodes, or tapeworms, constitute the class ____ of the phylum ____.
Cestoda; Platyhelminthes
All adult tapeworms have a white body and a ____-like appearance.
eong kalaban ng Goldilocks!
ribbon-like
All cestodes are hermaphroditic, otherwise known as ____.
monoecious
What do you call the attachment organ in the anterior portion of a tapeworm?
scolex
What do you call the portion immediately posterior to the scolex where new segments continuously grow?
neck
What do you call the segments of a tapeworm that grows from the neck?
proglottids
also known as strobila
The new segments are referred to as ____ because they do not yet contain fully developed internal structures.
immature
The ____ segments are larger and are found near the middle of the chain, and may contain set/s of reproductive organs.
mature
The terminal portion of the strobila contains the ____ segments, usually filled with eggs.
gravid
or ripe
In the adult worm of cestodes, the eggs are enclosed in the ____, a structure that varies in shape and size and serves as an important diagnostic feature.
uterus
Terminal proglottids may become detached in the intestine and pass out with the stool in a process called ____.
apolysis
All tapeworms inhabit the ____, where they live attached to the mucosa.
small intestine
Tapeworms do not have a digestive system. Instead, nutrients are absorbed from the host’s intestine through the ____.
tegument
The tapeworms are classified into two orders, order ____ and order ____.
- Order Pseudophyllidea
- Order Cyclophyllidea
False & True tapeworm
All cestodes have four muscular, cuplike suckers on the scolex except the tapeworms from what order?
order Pseudophyllidea
Cestodes under the order Pseudophyllidea possess a scolex bearing grooves called ____ instead of suckers.
bothria
The scolex may have an elongate and protrusible structure called ____ that is situated in the center of the scolex.
rostellum
Depending on whether hooks are present or not, the crown of scolex may be ____ or ____.
armed or unarmed
In general, cestodes’ extraintestinal infection with the ____ forms is a much more serious matter than infection with the adult worm.
larval
What are the three shapes (kinds) a scolex may have?
- Quadrate
- Globular
- Spoon-like
Identify the order of tapeworm being described
Dibothriocephalus latus is a member
Order Pseudophyllidea
Identify the order of tapeworm being described
Scolex is/has:
- Spoonlike, almond-shaped, spatulate
- 2 slitlike grooves called bothria
- No rostellum and no hooks
Order Pseudophyllidea
Identify the order of tapeworm being described
Scolex is/may:
- Quadrate
- possess rostellum
- possess 4 cuplike suckers
Order Cyclophyllidea
Identify the order of tapeworm being described
Its strobila is Anapolytic
Order Pseudophyllidea
Identify the order of tapeworm being described
Its strobila is Apolytic
Order Cyclophyllidea
Identify the order of tapeworm being described
The gravid proglottid has:
- all reproductive organs still present
- a rosette uterus
Order Pseudophyllidea
Identify the order of tapeworm being described
The gravid proglottid has:
- degenerate reproductive organs
- only the uterus and its lateral branches are seen
Order Cyclophyllidea
Identify the order of tapeworm being described
The uterine pore is present and located on the median ventral surface
Order Pseudophyllidea
Identify the order of tapeworm being described
The uterine pore is absent
Order Cyclophyllidea
Identify the order of tapeworm being described
The ova may be described as:
- Oval
- Operculated
- Unembryonated
Order Pseudophyllidea
Identify the order of tapeworm being described
The ova may be described as:
- Spherical
- Non-operculated
- Embryonated
Order Cyclophyllidea
Identify the order of tapeworm being described
The larval stages present are:
- Coracidium
- Procercoid
- Plerocercoid
Order Pseudophyllidea
Identify the order of tapeworm being described
The larval stages present are:
- Cysticercus
- Cysticercoid
- Hydatid cyst
Order Cyclophyllidea
Identify the order of tapeworm being described
Has 2 intermediate hosts namely:
- crustaceans/copepods
- freshwater fishes
Order Pseudophyllidea
Identify the order of tapeworm being described
Has 1 intermediate host: lower animal forms, man
some do not require intermediate hosts
Order Cyclophyllidea
What is the former name of Dibothriocephalus latus?
Diphyllobothrium latum
Although infection of Dibothriocephalus latus is relatively harmless, it may produce a condition called ____ due to the selective absorption of vitamin B12 from the intestines.
pernicious anemia
which leads to erythropoiesis impairment then macrocyte production
What do you call the embryo that the membranes of a tapeworm egg protect?
oncosphere
usually described as hexacanth embryo
hexacanth = hexa = 6 small hooks (hooklets) r present (3 pairs)
largest tapeworm of man?
Dibothriocephalus latus
Some cestode species utilize humans only as definitive hosts, growing to adulthood in the intestine after the ingestion of infective larva. What are these spp.?
- Dibothriocephalus latus
- Taenia saginata
- Hymenolepis diminuta
Some cestode species utilize humans as both the definitive or intermediate hosts. What are these spp.?
- Taenia solium
- Hymenolepis nana
Other cestode spp, such as ____, utilize humans as one of their possible intermediate host but never as the definitive host.
Echinococcus
Which of the cestodes consider man as an accidental host?
- Dipylidium caninum
- Hymenolepis spp.
- Echinococcus spp.
Which of the cestodes have their gravid segments wider than longer?
Dibothriocephalus latus
Which of the cestodes have their mature segments wider than longer?
- Dibothriocephalus latus
- Taenia solium
- Taenia saginata
Which of the cestodes have all segments wider than longer?
- Hymenolepis nana
- Hymenolepis diminuta
Which of the cestodes have its mature and gravid proglottid longer than wide?
Dipylidium caninum
True or False
The embryonated egg of beef tapeworm is the infective stage to humans
False
IS is larva: Cysticercus bovis
True or False
The eggs of Taenia solium and Taenia saginata is indistinguishable from each other.
True
True or False
Taenia solium adult is longer than Dibothriocephalus latus adult
False
longest tapeworm si D. latus
What is the infective stage of rat tapeworm?
Cysticercoid larva
rat tapeworm = Hymenolepis diminuta
What is the scientific name of the only tapeworm that may or may not require an intermediate host?
Hymenolepis nana
True or False
Taenia solium egg is the infective stage to humans?
True
but book said na egg is an infective stage
but ma’am said na false daw (but buk)
What do you call the intradermal test to diagnose Hydatid disease?
Casoni Intradermal Test
Polar filaments is diagnostic to what tapeworm?
Hymenolepis nana
Presence of two genital pores in a proglottid is a diagnostic feature of what tapeworm?
Dipylidium caninum
What is the scientific name of the only tapeworm with operculated eggs?
Dibothriocephalus latus
True or False
Hydatid disease is seen in Hymenolepis diminuta
False