ANIMAL KINGDOM Flashcards
general features of animals
- mutlicellular eukaryotes
- diverse in form
- no cell wall
- sexual reproduction
- embryonic development
- heterotrophs
phylum Porifera
sponges: lack symmetry not organized into tissues, perforated by tiny holes, flagellated cells that draw water and any food particles will be trapped and ingested
phylum Cnidaria
- jellyfish, sea anemones, sea coral, and hydroids
- symmetry and tissues
- undergo extracellular digestion (digestion takes place in a body cavity)
- 2 tissue layers: ectoderm and endoderm
- radial symmetry and a nerve net
Phylum Platyhelminthes
- bilateral symmetry so they have cephalization (sense organ and nervous control)
- have 3 embryonic layers
- acoelomates (no seperation of body wall from digestive tract)
flat worms
- simple body design with definite head and organs
- parasitic
- incomplete gut with only one opening
(can’t feed, digest, and eliminate waste simultaneously) - lack a circulatory system (undergo oxygen diffusion)
- hermaphroditic (male and female parts, which makes reproduction easier)
Evolutionary transition: body cavity
- all bilaterally symmetrical animals have a cavity in their bodies
- circulation: fluids move to allow the movement of material
- movement: fluid makes muscle contraction difficult
- body organs: organs can function without being deformed by muscles
What kinds of body cavities in Animalia?
acoelomate: lack body cavity
psuedocoelomates: body cavity between meso and endoderm
coelomates: fluid-filled body cavity (gut is suspended alongside other organ systems)
Phylum Nematoda
- pseudocoelomates: first evolutionary phylum to have an internal body cavity
- nematodes, ellworms, and rotifers
- nematodes mouth- piercing organ, food will pass through the mouth through the sucking chamber of the muscles (pharynx), it continues until being eliminated by the anus
Phylum Mollusca
- coelom (body cavity) more functional than animals without coeloms
- only coelom without a segmented body
- radula: tongue-like rasping organ used to scrape algae off rocks
What are the 3 different classes of Mollusca
1) gastropods: snails, slugs: use a muscular foot to crawl, mantle secretes a small, hard protective shell
2) bivalves: include clams, oysters, and scallops, secrete a two part shell with a hinge
3) cephalopods: include octopuses and squids with a modified mantle cavity to create a jet propulsion system to propel them through water
Phylum Annelida
- key evolutionary trait: segmentation
- earthworms, brittle worms
- advantage of segmentation is that segments have different functions: reproduction, feeding
Phylum Anthropoda
- insects, crabs, shrimp, lobsters, crayfish, water fleas
- evolutionary trait: jointed appendages and exoskeleton (Made of chitin and provides placement for muscle attachment)
- helps protect against predator and slow water loss
What are Anthropodas that lack jaws called?
Chelicerates: spiders, mites, scorpions
What are Anthropodas that have mandibles called?
Mandibulates: insects, centipedes (1 pair of legs on each segment, milli-2) crustaceans (diverse aquatic animals- two pairs of antennae, 3 pairs of appendages, and various number of legs)
- compound eyes
Phylum Echinodermata
- sea stars, sea urchins, sea cucumbers, sand dollars, etc
- EVOLUTIONARY: dueterostome (anus forming before the mouth) and endoskeleton (hard calcium plate beneath sensitive skin)
- pentamourous symmetry
- water vascular system as feet to suction water for movement
