Invertebrate Zoology Flashcards

Flashcards based on lecture notes about animal biology, focusing on invertebrate phyla.

Radial Symmetry

Symmetry where body parts radiate from a central point.

Cnidaria

Phylum containing jellyfish, corals, and hydra.

Habitat of Cnidaria

Aquatic, mostly marine.

Body layers of Cnidaria

Two layers: epidermis & gastrodermis.

Key Structures of Cnidaria

Tentacles, mouth, gastrovascular cavity, cnidocytes (sting cells), nematocysts.

Reproduction in Cnidaria

Alternation of polyp (sessile) and medusa (swimming) stages.

Evolutionary Traits of Cnidaria

True tissues & nerves.

Homeostasis in Cnidaria

Diffusion for waste, nerve net for coordination.

Diversity of Cnidaria

Hydrozoa (hydra), Scyphozoa (jellyfish), Anthozoa (corals/anemones).

Ocelli

Eyespots that detect light.

Platyhelminthes

Phylum containing flatworms.

Classes of Platyhelminthes

Turbellaria (Planaria), Trematoda (Flukes), Cestoda (Tapeworms).

Habitat of Turbellaria

Fresh water, moist environments.

Key Structures of Turbellaria

Eyespots (ocelli), pharynx, cilia, gastrovascular cavity.

Reproduction in Turbellaria

Asexual (binary fission), Sexual (hermaphrodites exchange sperm).

Traits of Turbellaria

Cephalization (no brain), bilateral symmetry.

Diversity of Turbellaria

Mostly non-parasitic.

Life cycle of Turbellaria

Direct development, no larva.

Porifera

Phylum containing sponges.

Habitat of Porifera

Marine, sessile.

Body Plan of Porifera

Asymmetrical, porous, no tissue or organs.

Key Structures of Porifera

Osculum, pores (ostia), spongecoel, choanocytes (collar cells), spicules.

Reproduction in Porifera

Asexual (budding or fragmentation), Sexual (hermaphroditic).

Evolutionary Traits of Porifera

Simplest animals, multicellular.

Diversity of Porifera

Glass sponges, calcareous sponges, demosponges.

Homeostasis in Porifera

Circulates water to filter food, oxygen, and remove waste.

Ecological Role of Porifera

Filter feeders, shelter for marine organisms.

Appearance of Porifera

Porous, irregular shapes, soft or rigid.

Habitat of Trematoda (Flukes)

Internal parasites of vertebrates.

Key Structures of Trematoda

Oral sucker, ventral sucker.

Reproduction in Trematoda

Hermaphroditic or separate sexes.

Life cycle of Trematoda

Eggs -> miracidium -> snail -> sporocysts -> redia -> cercaria -> infect next host.

Traits of Trematoda

Adaptations for parasitism.

Diversity of Trematoda

Liver fluke & blood fluke.

Habitat of Cestoda (Tapeworms)

Intestines of vertebrates.

Key Structures of Cestoda

Scolex (hooks/suckers), proglottids (segments).

Reproduction in Cestoda

Hermaphroditic proglottids make eggs.

Life cycle of Cestoda

Eggs in feces -> ingested by animal -> cyst in tissue -> human eats uncooked meat -> adult worm.

Traits of Cestoda

No digestive tract, absorbs nutrients from host.

Diversity of Cestoda

Pork/beef tapeworms.