Chapter 33: Slide 124 Flashcards
Clade identified by molecular data, have the widest range of animal body forms
Lophotrochozoans
Lophotrochozoans have a ________ for feeding, others have a __________ larval stage, and few have _________
Lophophore; trochophore; neither
What are the 6 groups of Lophotrochozoans
Flatworms, Rotifers and Acanthocephalans, Ectoprocts, Brachiopods, Molluscs, and Annelids
Phylum Platyhelminthes includes
Flatworms
Where do flatworms live?
Marine, freshwater, and damp terrestrial habitats
Many are parasites, such as flukes and tapeworms
Flatworms
They are dorsoventrally flattened acoelomates
Flatworms
The gastrovascular cavity branches throughout the body
Flatworms
In Flatworms, the flat body increases _________ ________, placing all cells close to water, either in the surroundings or the gut
Surface area
Enables elimination of nitrogenous waste and gas exchange by diffusion across the body surface
Flat body surface area placing all cells close to water, either in the surroundings or the gut
When an organism grows without changing shape, ________ increases more rapidly than _________ _______
Volume; surface area
____________ organisms have proportionally less surface area over which exchange processes can occur
Larger
The surface area of structures is maximized by __________, flattening, folding, and ____________
Branching; projections
What in flatworms maintains osmotic balance with the surroundings
Excretory apparatus
The excretory apparatus consists of _____________
Protonephridia
Networks of tubules with ciliated structures called flame bulbs
Protonephridia
Networks of tubules with ciliated structures on Protonephridia
Flame bulbs
Pull fluid through branched ducts open to the external environment
Flame bulbs
What are the two lineages of Flatworms
Catenulida and Rhabditophora
Lineage of flatworms, AKA “chain worms”
Catenulida
Live in freshwater, and reproduce asexually by budding into chains of individuals
Catenulida
Lineage of Flatworms that are more diverse and can be found in both marine and freshwater habitats, and have free-living and parasitic species
Rhabditophora
Are Rhabditophorans that live in fresh water and prey on smaller or feed on dead animals
Planarians
They have light-sensitive eyespots as well as lateral flaps for the detection of chemicals
Planarians
The nervous system of __________ is centralized and more complex than that of Cnidarians
Planarians
Some __________ reproduce asexually by fission
Planarians