duterotomes Flashcards
(18 cards)
What are deuterostomes?
A group that includes the largest-bodied and some of the most morphologically complex of all animals
Deuterostomes share important features of embryonic development, such as the gut developing from posterior to anterior.
What is the embryonic development pattern of deuterostomes?
The gut develops from posterior to anterior
The coelom develops from outpocketings of mesoderm.
What are the main lineages of echinoderms?
- Crinoidea
- Asteroidea
- Ophiuroidea
- Echinoidea
- Holothuroidea
Echinoderms are marine animals with about 7,000 described species.
What are the synapomorphies of echinoderms?
- Radial symmetry in adults
- An endoskeleton of calcium carbonate
- A water vascular system with tube feet
Echinoderm larvae are bilaterally symmetric, but adults exhibit pentaradial symmetry.
What is the function of the water vascular system in echinoderms?
It forms a hydrostatic skeleton and plays a key role in feeding
The system consists of branching, fluid-filled tubes and chambers.
What is a hemichordate?
Mostly acorn worms, burrow-dwelling marine animals that are sessile deposit/filter feeders
Their larvae are pelagic plankton eaters.
What is a chordate?
An animal that has four morphological features at some stage in its life cycle
These features include pharyngeal gill slits, a dorsal hollow nerve cord, a notochord, and a muscular post-anal tail.
What are the three subphyla of Chordata?
- Cephalochordates
- Urochordates
- Vertebrates
Not all chordates are vertebrates, but all vertebrates are chordates.
What are cephalochordates also known as?
Lancelets or amphioxus
They are small, mobile suspension feeders that resemble fish.
What features do urochordates have?
- Pharyngeal gill slits
- Dorsal hollow nerve cord
- Notochord
- Muscular, post-anal tail
These features occur only in larvae or in sexually mature forms of motile species.
True or False: Echinoderms are all freshwater animals.
False
All echinoderms are marine animals.
What is the role of tube feet in echinoderms?
They are elongated, fluid-filled appendages that help in feeding and locomotion
Tube feet consist of an ampulla on the inside of the body and a tube-like podium projecting outside.
Fill in the blank: All chordates have openings into the throat called _______.
pharyngeal gill slits
What is the endoskeleton of echinoderms made of?
Calcium carbonate
The endoskeleton forms during development through the secretion of calcium carbonate plates.
What feeding methods do echinoderms utilize?
- Mass feeding
- Suspension feeding
- Deposit feeding
Tube feet play a key role in obtaining food.
What is unique about the body plan of echinoderms?
They have radial symmetry in adults and bilateral symmetry in larvae
Adults exhibit pentaradial symmetry.
What is the significance of echinoderms as consumers?
They are important consumers in marine ecosystems
Their role as keystone predators impacts community diversity.
What is the primary characteristic of the body plan of chordates?
Presence of a notochord
This rod provides support and is present at some stage in their life cycle.
