Animal Phyla Flashcards
(158 cards)
Porifera
Animals without tissues
Sponges
What type of body symmetry do sponges have?
Assymetrical or radial symmetric
How does a sponge gather food from their environment?
Filter feeding
How do the feeding mechanisms limit the kinds of food sponges can consume?
water drawn in through pores, contains bacteria and tiny particals, food in limited to smaller than the individual cells.
Eumetozoans and body symmetry
have true tissues which develop from distinct layers in the embryo.
Increase in complexity of functioning.
Radiata and bilatera
Radial symmetry
sense stimuli in all directions
life in open water
Cnidiria and ctenophora
Tissues but no organs or coelom
Diploblastic
Single opening - gastrovascular cavity with digestive and circulatory functions
gelatinous mesoglea btwn 2 layers
gas exhange and excretion via diffusion
cells cloase to body surface
Phyla Cnidiria
Mainly marine
Specialised cells for prey capture = cnidocytes with nematocysts
Polyps or medusa with tenticles tha surround the mouth
mesoglea and gatrovascular cavity differ in size
Simplest animals with specailsied tissues
Cnidirian digestion
Phagocytosis and intracellular digestion - vacuole
Digestive enzymes and extracellular digestion - gland cells
Cnidarian locomotion and hydrostatic skeleton
Skeleton = gastrovasular cavity in polyps and mesoglea in medusa’s
Locomotion = circular fibrils and longitudinal fibrils
Cnidiria lifecycle
Lifecycle can alter btwn polyp and medusa
polyp reporduces asexually
medusa reproduce sexually
4 cnidiria lineages/classes
Hydrozoa - polyp and medusa stages, polyps form sessile colonies
Scyphozoa - Jellyfish, bell shaped medusa
Cubozoa - box jellies, cube shaped medusa, poisonous toxin
Anthozoa - coral and anemones, sessile polyps
Bilateral Symmetry
Triploblastic
coelom or pseudocoelom
have organ systems
sensory organs = cephilisation
sister clades - Protosomia and deutersomia
Protosomes
Lophophorates = have a lophophore
circular or U shaped tentacles around mouth
gas exchange, feeding and excretion
sessile filter-feeders
coelomate and have complete digestive system
Marine animals
How do cnidirians capture, comsume and digest their prey?
Why is feeding more efficeint in cnidirians than protozoa even though there is still no digestive system?
which group of cnidirians only have a polyp stage?
Anthozoa
In which groups does the medusa stage predominate?
Hydrozoa, Cubozoa and Scyphozoa
How can cnidiarians and sponges complete bolily functions without organs?
Through diffusion
Phyla Plathelminthes
Aquatic environments
Acoelomate = no cloelom
No ciruclatory or respiratory organs = via diffusion
Plathelminthes ectoderm layer
Epidermis with ladder like nervous system,longitudinal ventral nerve chords and fibres
primitive brain=ganglioin
Eye spots in free living species
Flame cell system for excretory system.
Plathelminthes mesoderm layer
Forms the reproductive system and muscles
Plathelminthes endoderm layer
forms highly branched digestive system
One opening
Plathelminthes lineages/classes
Turbellaria - free living, with eyespots, food ingested and excreted through mouth, Hermaphroditic sexual reproduction, mostly asexual.
Trematoda - fluke, internal parasites in gut, liver, lungs, blood vessles of vertabrates. Complex life stages + multiple hosts
Monogenoidea - flukes, external parasites, gills or skin of aquatic vertabrates, single hosts, have suckers and hooks.
Cestoda - tapeworms, endoparasites, no digestive system, hooks and suckers, proglottids= repeating segements, contains reporductive systems.
why is it important that flatworms are only a few cm thick?
Body processes occur through diffusion