Multicellular Eukaryotic Parasites Topic 5 Pre-Midterm Flashcards
Where do endoparasites live?
They live inside the body
What is an example of an endoparasite?
Tapeworms and Roundworms
What is the life cycle like for endoparasites?
Complex life cycles with several hosts
Where do enctoparasites live?
They live on the body (often only when feeding)
What is an example of ectoparasites?
Leeches, arthropods (mites, ticks, insects)
Ectoparasites and vectors
May serve as vectors for other pathogens
What are the three types of worms?
Flatworms, unsegmented round worms, and segmented round worms
What are the two types of anthropods?
Insects and (mites and ticks)
Ectoparasites may serve as what for other pathogens?
Vectors
Do leeches transfer diseases?
No
Give an example of an ectoparasite that can serve as a vector?
Mosquito
What are the two types of flatworms?
Tapeworms, Flukes
What is an example of a tapeworm?
Taenia
What is an example of a fluke?
Schitosoma
What is the one type of non-segmented round worm? and example
Nematode eg. Ascaris
What is the one type of segmented round worms?
Leeches
Simply describe the lifecycle of the flatworm and tapeworms?
Complex with multiple hosts
What host is the human in a flatworm and tapeworm?
Definitive host and/or intermediate host
Define the definitive host in a flatworm and tapeworm?
Where the parasite reaches maturity, and produces sexually
Define the intermediate host in a flatworm and tapeworm?
Houses the immature (larval) stage of the parasite
What host does sex always occur in (tapeworm and flatworms)
Definitive host
If reproductive happens in the intermediate host, what type of sex is it?
Asexual in the larval
What is the term for a tapeworm infection?
Taeniasis
What is the definitive host in the beef tapeworm?
Human
What is the intermediate host in the beef tapeworm?
Cow
Where does the larval stage happen in a beef tapeworm?
The larval stage encyts in cow muscle and is ingested by human (obtained from uncooked beef)
What host is the human in the pork tapeworm?
Definitive or intermediate host
Where does the final form live in the pork tapeworm?
In the intestine, intermediate for cause cysticercosis of muscle, nervous tissue, or eyes
How does a tapeworm complete their lifecycle?
They have to go through 2 or more different hosts (some need to go into specific hosts, if they are in the wrong host, they will die)
How do you get the beef tapeworm?
By consuming uncooked meat (the worm dies at 56 degrees)
Simply describe the steps of the beef tapeworm? (Cows –> Human)
- Human consumes meat that has cysts in the muscle
- Grows as adult in human small intestine
- Eggs released in feces
- Consumed by cow
What is the scolex of a beef tapeworm?
“Head”
- has suckers and hooks
What are the proglottids?
- Body segments
- Each contains ovaries and testis
- Fill with eggs and are shed with feces
- Don’t have internal organs
What are the sex organs of proglottids?
- Ovary
- Uterus
- Testes
What host is the human in a pork tapeworm?
The definitive or intermediate host
Definitive = Ate pork that had larva inside the meat
Intermediate = Ate the eggs
Describe the lifecycle of a pork tapeworm?
See slide 14
What happens in cysticercosis?
The human is the intermediate host due to ingestion of eggs
- Larvae are able to invade tissue (muscle, eye, brain, spinal cord, heart)
- Don’t grow into adult form or reproduce in intermediate host
How can cysticercosis happen?
May have ate vegetables that were raw
What is neurocysticercosis (NCC)?
Larval cysts travel to the brain
- The most common parasitic infection of CNS
How many hosts may tapeworms go through?
4 or 5
Tapeworms for pets
The larva lives inside the flea (flea is the intermediate host), the dog needs to eat the flea to complete the life cycle
