Sponges and Cnidarians

Sponges and

Cnidarians

Sponges

Sponges Intro.

OriginEvolution: believed to have evolved from protists

Collar cells: are almost identical to many flagellated protist cells Uses of collar cells:▪ Move water, ingest

food and excrete waste

Sponges Intro, cont.Diversity

Species #: 8300

Variety: 3% live in

freshwater Variety of

shapes, sizes and colors

Live at a variety of sea depths

Characteristics of SpongesKingdom Animalia

Phylum PoriferaThey are mostly marine (live in salt water)

# of cells: multicellular (eukaryotic)

Body contains pores, canals and chambers that allow for water flow

Characteristics of Sponges

Symmetry: radial No definite head regionInterior surface: lined with collar cells (choanocyte) Choanocyte:

▪ a flagellated collar cell that lines the inner surface (mesophyll) of sponges

ChoanocyteBeating flagella

Create water current

Capture food and water particles

Carries away waste

ChoanocyteCollar is made of microvilli Why? To create a filtering device to collect food

ChoanocyteThe food particles then become trapped How? Taken in by the food vacuoles (where they are stored and digested)

Actual Choanocyte at work

Food and Oxygen ExchangeEfficient? Non-efficient?

Why?▪ Lots of collar cells working together

Structure of a SpongeMade of ?

Spicules – calcareous or siliceous, support structures

Spongin – fibrous proteins, made of collagen

Spicules

SponginFun fact:

When you wash with natural

sponges, this is the portion you wash/exfoliate

with!

Spicules & Spongin

Characteristics of SpongesReproduce asexually or

sexually By? Budding or gemmules (asexual),

sperm and egg (sexual)Larva: motile, moveAdults: sessile, don’t move

Budding

SexualSponge Love Scene

#2

Sponge Love Scene #1

Gemmule

Three Main Body Types

1. Asconoid Def: one large

body cavity Characteristics

:▪ Collar cells line

the main body cavity

▪ Contain many pores

Three Main Body Types

2. Syconoid Def: many

canals, water flows through each canal

Characteristics:▪ Collar cells line

canals▪ Can filter more

water

Three Main Body Types

3. Leuconoid Def: contains

chambers Characteristi

cs: collar cells line

chambers Often used for

shower sponges

Classification of Sponges

Kingdom: Animalia Phylum: Porifera Class CalcareaClass HexactinellidaClass Demospongiae

Class CalcareaSpicules

Made of calcium carbonate (like baking soda)

Shape: needle shaped, 3-4 sections/rays

Body types? All three types represented

Class HexactinellidaSpicules

Made of? Silica (glass-like) Description: Six sections/rays

Body types? Asconoid or leuconoid

Often called? Glass sponges

Class Hexactinellida

Class DemospongiaeSpicules

Made of: silica Description: don’t have 6 rays

Body types? Leuconoid onlyOther characteristics:

Make up 95% of all sponges Use this type in bath/shower

Class Demospongiae

Cnidarians

Characteristics of CnidariansKingdom Animalia

Phylum CnidariaExamples:

Hydra, sea anemone, jellyfish, Portuguese-man-o-war, moon jelly, sea pen, coral

Where do they live??? Aquatic (mostly marine/salt-water)

Characteristics of Cnidarians

Symmetry: Radial or biradial Head region? No definite head

region Two basic types:

1. Polyp: tentacles facing upwardsEx: sea anemone, coral

2. Medusa: tentacles facing downwardsEx: jellyfish, man-o-war

Polyp FormPolyp –

Lifestyle of polyps? Sessile (do not move)

Body shape? Tubular (tube-like) Mouth: Surrounded by tentacles

(facing up)

Medusa FormMedusa –

Lifestyle? Mobile/motile (move) Body shape? Umbrella shaped Mouth : surrounded by tentacles

that face downwards

Life CycleBody forms? Most cnidarians

exist as BOTH body forms at some point during their life cycle

POLYMORPHICReproduction

Polyp: reproduce asexually using budding

Medusa: reproduce sexually using sperm/egg

Life Cycle

Characteristics of CnidariansTwo layered body

Epidermis – ▪ Def: outer part of the body▪ Derived from? Ectoderm

Gastrodermis – ▪ Def: inner part of the body▪ Derived from? Endoderm▪ Lines the gut cavity▪ Main function: digestion

Characteristics of Cnidarians

Characteristics of Cnidarians

Tentacles contain cnidocytes Function: aid in capture of

prey/food Characteristics: armed with

nematocysts Nematocyst: stinging cell (contains

hook/barb used to catch)

NematocystStinging cellsContain filamentWhen do they uncoil? When they are touched by animals (in the environment)

Contain barb or spinePoisons can be injected

Nematocysts

Nematocyst

Firing

Nematocyst Firing

Four Classes of Cnidarians

Class Hydrozoa

Class Scyphozoa

Class Cubozoa

Class Anthozoa

Class HydrozoaSolitary (live as an individual)Colonial (live in groups)Reproduce? Asexually (Polyp

form) OR sexually (medusa form)Where do they live?

Freshwater OR marine/salt-waterExamples: Hydra, Tubularia

Hydra

Obilia

Polyp Medusa

Physalia

Class ScyphozoaMovement: Solitary (live by

themselves, but MOVE quiet a bit)Body form: Medusa form (most)Where do they live? All

marine/salt-waterOrgans? Sensory organs found on

the ridge of the umbrellaExamples: Cassiopeia, Aurelia

Aurelia

Cassiopeia

Class CubozoaMovement: Solitary (live by

themselves but MOVE quite a bit)Body form: Medusa form (most)Where do they live? All

marine/salt-waterCharacteristics? Umbrella is more

square in shapeExamples: Tripedalia, Carybdea

Carybdea

Chiropsalmus

Class AnthozoaMovement: Solitary (individual)or

colonial (group); tentacles move some (but animals are fixed to a spot, usually)

Body form: all polyps (no medusas!)

Where do they live? All marine/salt-water

Examples: Exist in three subclasses

▪ Subclass Hexacorallia▪ Subclass Ceriantipatharia▪ Subclass Octocoral

Hexacorallia

Ceriantipatharia

Octocorallia

Sponges and Cnidarians in BiosphereHuman Uses

Bioindicators: provide info about the environment/oceans/water bodies▪ Sponges

▪ Filter water ▪ Pollutants are concentrated in collar cells

▪ Corals: ▪ sensitive to water pollution (loose coloration)

Help protect shore line from erosion (decrease force of waves)

Sponges and Cnidarians in Biosphere Biomedical/Pharmaceutical industry1. New antibiotics2. Anticancer compound found

in small % of sponges

Consumer products1. Natural sponges (bathing)2. Spicules used in clay to

strengthen ceramic pots, etc

Sponges and Cnidarians in BiosphereIn the Environment

Form of food, camouflage and protection for other animals

Many symbiotic relationships Corals and Sponges

▪ The most abundant animal in most reefs▪ Base of most aquatic food chains▪ May be used as camouflage

▪ Ex: Crab species place sponges on their backs for protection

Sponges and Cnidarians in BiosphereOther relationships

Cnidarians with dinoflagellates(protists)—▪ Form reefs when this relationship occurs

Homes for other organisms ▪ Shrimp, clown fish and eels use sponges as

homes▪ Coral reefs provide protection