Chapter 31 Flashcards
Protostome Animals
What are protostomes?
Protostomes are the most diverse and abundant group of animals.
All arthropods are protostomes.
What is a muscular hydrostat?
A biological structure found in animals, primarily composed of muscle tissue with no supporting skeleton, which allows for complex movements by manipulating its shape through muscle contractions, essentially acting like a fluid-filled chamber despite not having a separate fluid cavity
A muscular hydrostat is a hydrostatic skeleton found in snails and chitons, characterized by a large muscular foot at the base.
What is the visceral mass in mollusks?
The visceral mass is the region in all mollusks where organs and surrounding fluids are located.
What is the radula?
The radula is a unique feeding structure in mollusks that functions as a file, moving back and forth over food sources.
What is the mantle in mollusks?
The mantle is an outgrowth of the body wall that covers the visceral mass, forming an enclosure called the mantle cavity.
What is the most important phylum within Ecdysozoa?
Arthropods are the most important and abundant phylum within Ecdysozoa.
What are the major groups of arthropods?
The major groups of arthropods are Myriapoda (e.g., centipedes), Crustacea (e.g., shrimp, lobsters), Insecta (e.g., insects), and Chelicerata (e.g., spiders).
What is significant about insect flight?
Insects were the first animals to achieve powered flight, with evidence suggesting that wings evolved only once before the adaptive radiation of insects on land.
What are the two types of metamorphosis in arthropods?
The two types of metamorphosis in arthropods are incomplete metamorphosis and complete metamorphosis.
What is incomplete metamorphosis?
Incomplete metamorphosis is a form of direct development where juveniles, called nymphs, look like smaller versions of the adult.
What is complete metamorphosis?
Complete metamorphosis is a form of indirect development that includes a distinct larval stage.
How common is complete metamorphosis compared to incomplete metamorphosis?
Complete metamorphosis is 10 times more common than incomplete metamorphosis.
What adaptation do flatworms have for gas exchange?
Flatworms have a high surface area that helps them with gas exchange and breathing.
What are segmented worms?
Segmented worms are coelomate worms that have an enclosed coelom completely lined with mesodermally derived tissue.
What are roundworms classified as?
Roundworms and other pseudocoelomates have an enclosed coelom partially lined with mesodermally derived tissue.
What is the classification of worms?
Worms are considered polyphyletic.
What are Arthropods
Arthropods are invertebrates in the phylum Arthropoda. They possess an exoskeleton with a cuticle made of chitin, often mineralised with calcium carbonate, a body with differentiated segments, and paired jointed appendages.
