Vertebrates and Invertebrates Flashcards
What do annelids include?
-Leeches
-Earthworms
Segmentation
the subdivision of the body along its length into a series of repeated part, a nervous system, and a closed circulatory system
Closed circulatory system
blood remains enclosed in vessels throughout the body.
Open circulatory system
Blood is pumped through vessels into open body parts
Arthropods include:
crayfish
lobsters
crabs
barnacles
spiders
ticks
insects
Arthropod features
-segmentation
-exoskeleton
-jointed appendages
-sheds exoskeleton
Molting/ecdysis
shedding exoskeleton
How do arthropods have such success?
-body segmentation
-exoskeleton
-jointed appendages
-flight
-waterproof cuticle
-complex life cycle with short generations and large numbers of offspring
What species to Echinoderms include?
-sea star
-sand dollar
-sea urchins
Qualities of Echinoderms
– slow-moving or sessile,
– all marine,
– radially symmetrical as adults, and
– deuterostomes
Deuterostomes
the first opening (the blastopore) becomes the anus, whereas in protostomes, it becomes the mouth; same for chordates)
Features of Chordates
– a dorsal, hollow nerve cord,
– a flexible, supportive, longitudinal rod, the notochord,
– pharyngeal slits, and
– a muscular post-anal tail.
What phylum do humans belong to?
Chordata
Hagfish and Lamprey features:
-have rudimentary vertebrae,
-have a notochord for the body’s main support, and
-lack hinged jaws.
What animals are included in jawed vertebrates with paired gills and fins?
SHARKS, Ray-Finned Fishes,
and Lobe-Finned Fishes
When did jawed vertebrates appear?
440 MYA
How did jaws evolve?
Jaws may have evolved by
modifications of skeletal supports of
the anterior pharyngeal (gill) slits.
What is the purpose of gills?
The remaining gill slits remained as sites of gas exchange(extracting oxygen from water)