Chapter 31 Flashcards
(109 cards)
Animals share a common ___ ancestor
choanoflagellate
Sponges are assigned to a ___ group, ___ due to asymmetry and simple body plans
basal group, Parazoa
Animals with true tissues are classified as
Eumetazoa
Sponges are apart of phylum
Porifera
___ are aquatic feeders, primarily marine
Poriferans
Characteristics of Sponges
- Flagellated collar cells
- Larvae have flagella; adults are sessile
- Cells do not form true tissues
- Water circulates in three types of canal systems (Asconoid, Syconoid, Leuconoid)
- Fibrous part of the sponge skeleton consists of a form of spongin
- Gas exchange and excretion depend on diffusion
- Sponges do not have specialized nerve cells
Sponges reproduce by ___ and ___
Sponges reproduce by fragmentation and sexually
most sponges are ___
hermaphrodites
Three main groups of sponges
- Calcareous sponges
- Glass sponges
- Demosponges
Calcareous sponges
class: Calcarea
Skeleton either mesh or honeycomb structure
Glass sponges
class: Hexactinellidae
six ray
Demosponges
Class: Demospongiae
People sponge
Class Demospongiae
Freshwater: found in clean ponds and streams in eastern North America
Siliceous spicules with one to four rays and/or spongin fibers
Cnidarians are apart of phylum
Cnidaria
___ are mostly marine animals with radial symmetry
Cnidarians
Cnidarians have a ___ and ___ body shapes
Polyp and medusa
___ contain stinging nematocysts
Cnidocytes
Gastrovascular cavity has a single opening that serves as both ___ and ___
mouth and anus
Cnidarians are
diploblastic
Cnidarians Nerve cells form
nerve nets
Cnidarians have a ___ skeleton
hydrostatic skeleton
Cnidarian body plan: Nervous systes
Lack a Centralized nervous system
Nerve net
Medusa have more complex nervous system with sense organs
Nerve net Cnidarian Body Plan
one between the epidermis and the mesoglea and another between the gastrodermis and the mesoglea
Coral Reefs consist of
corals and red algae