Flatworm Basics
The name of this animal group literally means “flat worm.”
What is platyhelminthese?
These mostly free-living flatworms include organisms commonly studied in freshwater environments.
What are planarians?
These tiny structures on the underside of a planarian beat together to help move it forward.
What are cilia?
Most flatworms can reproduce through both of these two methods.
What is sexual and asexual reproduction?
In the life cycle described in the notes, this animal serves as the intermediate host for the blood flukes responsible for a major parasitic disease.
What are snails?
This type of symmetry allows an animal to be divided into matching left and right halves.
What is bilateral symmetry?
Members of this class commonly attach to host tissues (blood, liver, etc.) using two suckers.
What are flukes?
Because these animals lack a formal respiratory system, oxygen enters and carbon dioxide leaves primarily through this process.
What is diffusion?
An animal with both male and female reproductive structures is described by this term.
What is a hermaphrodite?
These two animals are often sources of human tapeworm infections.
What are cows and pigs?
Unlike sponges and cnidarians, these animals develop three embryonic tissue layers, including a middle layer.
What is a triploblast?
These segmented parasites absorb nutrients directly from the food being digested by their hosts.
What are cestodes?
In a planarian, this muscular tube extends toward food, releases digestive substances, and draws partially digested food into the digestive cavity.
What is the pharynx?
During this type of asexual reproduction, a planarian separates into two pieces, and each piece develops into a new worm.
What is fission?
This disease caused by blood flukes can produce abdominal pain, diarrhea, blood in the urine, and organ damage.
What is schistosomiasis?
This term describes animals that lack a body cavity
What are acoelomates?
This class includes parasites that usually live on the outside of a single host, commonly a fish.
What are monogeneans?
These paired cords run along the underside of the body and connect through crosswise nerves.
What are the ventral nerve cords
Many parasites exhibit this type of life cycle that involves multiple hosts
What is complex?
This disease can develop when immature pork tapeworms form cysts in human tissues, including the brain or muscles.
What is cysticercosis?
The concentration of nervous tissue at one end of an animal's body, forming a head region, is known by this term.
What is cephalization?
This class contains approximately 20,000 species according to the notes and includes organisms that may live in a host's blood or liver. They are commonly called flukes
What are trematodes?
This primitive waste-removal system contains specialized cells with internal flagella that help move excess water and waste.
What is the protonephredia system
Each of these contain both testes and ovaries in tape worms.
What are proglottids?
This disease occurs when adult parasitic worms live in a human's intestines after infection from contaminated meat.
What is taeniasis?