06 benthos
This presentation is the property of its rightful owner.
Sponsored Links
1 / 72

06 BENTHOS PowerPoint PPT Presentation


  • 47 Views
  • Uploaded on
  • Presentation posted in: General

06 BENTHOS. I.Sponges (Phylum Porifera) A.Evolutionary history 1.Fossil sponges are some of the oldest known multi-celled animals . Fossil Sponge Showing a Honey-combed Pore Pattern. Fort Scott Limestone in Bourbon County, Kansas. A.Evolutionary history (continued)

Download Presentation

06 BENTHOS

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


06 benthos

06 BENTHOS


06 benthos

  • I.Sponges (Phylum Porifera)

  • A.Evolutionary history

    • 1.Fossil sponges are some of the oldest known multi-celled animals


06 benthos

Fossil Sponge Showing a Honey-combed Pore Pattern

Fort Scott Limestone in Bourbon County, Kansas.


06 benthos

A.Evolutionary history (continued)

2.In phylogenic studies, sponges have been treated as a sister group to the other animal (= Metazoa) taxa.


06 benthos

  • Evolutionary history

  • 3.Recent genetic evidence, however, suggests that the ctenophores may have separated from the other animals before the sponges


06 benthos

Major events of loss and gain in the evolution of early animal tissue complexity are suggested by the analysis of the first representative genome from the ctenophore phylum

http://www.sciencemag.org/content/342/6164/1327/F1.large.jpg


06 benthos

  • I.Sponges (continued)

  • B.Body parts

    • Epithelial cells only (no muscle, connective, nor nervous tissue)

    • Structural protein SPONGIN

  • (1)Coarse collagen fibers

  • (2)Responsible for resilient and absorbent properties of sponge skeleton


06 benthos

Spongin Fibers

http://media.photobucket.com/user/Zoology1/media/kingdom%20Anamalia/Porifera/Spongefibers2.jpg.html?filters[term]=spongin&filters[primary]=images&filters[secondary]=videos&sort=1&o=0


06 benthos

B. Body Parts of Sponges (continued)

3.SPICULES

a.Deposits of…

(1)Calcium carbonate

(2)Silica

b.Function to…

(1)…provide structural strength especially in narrow passageways

(2)…inhibit predation


06 benthos

Spicules from an Hexactinellid Sponge

Figs. 5-9A & B, p. 84


06 benthos

Spicules from modern sponge

Magnification = 100X

http://media.photobucket.com/user/paulfuentebella/media/Lab%2012/IMAG0164.jpg.html?filters[term]=grantia%20spicules&filters[primary]=images&filters[secondary]=videos&sort=1&o=0


06 benthos

Spicules from a Fossil Sponge Stained Orange by Iron Oxide

Lower Ordovician, Idaho

http://www.fallsoftheohio.org/Fossil_Sponges.html


06 benthos

I.Sponges (continued)

C.Rely upon currents to filter-feed


06 benthos

C.Filter-feeding currents (continued)

1.Water flow

a.Enters through external pores into small passageways known as CHOANOCYTE CHAMBERS

(1)Lined by cells called CHOANOCYTES

(2)Food particles are captured

b.Processed water enters a CENTRAL CAVITY

c.Waste water leaves via openings called OSCULA [= little mouth; osculum = sing.]


06 benthos

Central Cavity

Central Cavity

Arrows show locations of oscula


06 benthos

Summary of Filter-feeding in Sponges


06 benthos

C.Filter-feeding currents (continued)

2.Control of feeding currents

a.Some sponges can pass their own weight in water every 5 seconds


06 benthos

Cheap Thoughts

By

Jack O’Brien

How does an organism with no muscles “pump” water through its body?


06 benthos

2.Control of feeding currents (continued)

b.BERNOULLI'S PRINCIPLE:

(1) A decrease in the X-sectional area of a pipe causes an increase in the velocity of a liquid flowing through that pipe (river moves slowly in wide portions of a canyon and rapidly in a narrows)

(2)The volume of a fluid passing by any point remains the same, so a decrease in the X-sectional area at a point results in an increase in flow


06 benthos

The relationship between the area of a tube and the velocity of a non-compressible fluid passing through that tube. (The lengths of the arrows labelled v represent relative velocities of the fluid.)

http://titans.s716.ips.k12.in.us/~blachlym/pol/ch-09/5/5.htm


06 benthos

b,BERNOULLI'S PRINCIPLE (continued)

(3) Since the X-sectional areas of all the choanocyte chambers is greater than the area of the osculum…

(a)…the speed of the water current leaving the sponge at the osculum is greater than the speed of the water currents entering pores and the choanocyte chambers

(b)…waste water is carried away from sponge


06 benthos

More Cheap Thoughts

By

Jack O’Brien

Why don’t algae, barnacles and other encrusting or fouling agents grow on sponges?


06 benthos

Biofouling

http://www.tvja.org/science/fouling_community_study.htm


06 benthos

Sponges apparently use

“chemical warfare”

Science 2008, 320: 1030


06 benthos

Science 2008, 320: 1028


06 benthos

Currently there are numerous pharmaceutical companies sponsoring research on chemicals produced by sponges and their symbionts looking for medicinal properties.

This includes Johnson & Johnson original support of the Harbor Branch Oceanographic Institute in Ft. Meyers, FL now affiliated with Florida Atlantic University


06 benthos

The deep-water submersible Johnson-Sea Link

http://en.wikipedia.org/wiki/File:Johnson_Sealink.png


06 benthos

Florida Keys

Photo: J. O’Brien, 2011


06 benthos

Poriferans

Photo: J. O’Brien, 2011


06 benthos

Large Barrel Sponge

Photo: J. O’Brien, 2011


06 benthos

  • II.Mollusks

    • A.Adults lack obvious segmentation

    • B. Specialized structures

      • 1.RADULA

  • a.Rasping tongue-like structure

  • b.Can bore holes in prey or scrape algae from rocks

  • cPossesses a hhardness value of 6 on the Mohs scale

  • (1)Diamond hardness is 10

  • (2)Harder than poor grades of steel


  • 06 benthos

    EM of

    Radula


    06 benthos

    • Specialized structures (continued)

    • 2. Muscular FOOT

      • a. Movement

      • b. Attachment (limpets & abalone)

      • 3. Calcareous SHELL

      • 4. MANTLE

      • a.Thin layer of tissue under shell

      • b.Lays down shell

      • c.Respiratory organ


    06 benthos

    Keyhole Limpet with Mantle Covering External Shell


    06 benthos

    • Specialized structures (continued)

    • 5. MANTLE CAVITY

      • a.Space between mantle & body organs

      • b.Location of GILLS

      • c.Inhalant and exhalant feeding currents

      • move through it


    06 benthos

    II. Mollusks (continued)

    C.Most marine mollusks have a TROCHOPHORE larva that develops into a VELIGER


    06 benthos

    Castro & Huber

    2003, p. 332

    TROCHOPHORE larva

    Found in Annelids and Mollusks


    06 benthos

    • D.Gastropoda

      • 1.Most diversified molluscan class (35,000 species)

      • 2.OPERCULUM

        • a.On coiled shelled gastropods

        • b.Hard plate that covers aperture when foot withdrawn

        • c.Functions

        • (1)Protection

        • (2)Prevents desiccation


    06 benthos

    Operculum of a Whelk

    http://barnegatshellfish.org/images/whelk/operculum_whelk_bb_01_l.PNG


    06 benthos

    • D.Gastropoda (continued)

    • 3.Neogastropods

      • a.Characteristics

        • (1)Extendible BUCCAL TUBE or PROBOSCIS (snout) with mouth at end

        • (2)Portion of mantle forms a SIPHON

        • (3)Shell has a SIPHONAL CANAL


    06 benthos

    • Neogastropods (continued)

    • Examples

    • (1) Whelks common in seagrass habitats


    06 benthos

    Siphonal Canal

    Siphon

    Buscyon, Lightening whelk feeding on a bivalve

    Lippson & Lippson, 1984, Life in the Chesapeake,p. 53


    06 benthos

    Whelk egg string

    Photo: J. O’Brien 2013

    Common whelklaying eggs

    Picture: Ron Offermans http://molluscs.at/gastropoda/index.html?/gastropoda/sea/common_whelk.html


    06 benthos

    Coral Reef Gastropods

    Photo: J. O’Brien, 2011


    06 benthos

    Conchs in a Boat

    Photo: J. O’Brien, 2011


    06 benthos

    Conchs on a Shelf

    Photo: J. O’Brien, 2011


    06 benthos

    Conchs in Space

    Photo: J. O’Brien, 2011


    06 benthos

    • Examples of neogastropods (continued)

    • Cone Shells

    • (a)Predators on tropical reefs

    • (b)Teeth of radula are harpoon-like

    • (c)Contain venom

    • (d)Stabbed into prey by proboscis


    06 benthos

    Cone Shells with Names Carved into Shell

    Photo: J. O’Brien, 2011


    06 benthos

    E.Bivalves

    1.Structures

    a.Shell formed of two valves

    b.LIGAMENT acts to spring open valves

    c.Large powerful ADDUCTOR MUSCLES close valves

    (good tasting)


    06 benthos

    Clam and Mussel

    Painting by Georgia O’Keefe, 1926


    06 benthos

    • Bivalves (continued)

    • Filter-feeders

    • a.Gills covered with mucus

    • b.Trap suspended particles (= plankton)

    • c.Cilia carry food to mouth

    • d.LABIAL PALPS

      • (1)Reject unsuitable food

      • (2)Form PSEUDOFECES


    06 benthos

    • Bivalves (continued)

    • Life-styles

    • a.Most bury in unstable substrates

    • b.Dig by contracting valves and moving foot

    • c.Siphon extends up into water column


    06 benthos

    siphons


    06 benthos

    • Bivalves (continued)

    • 4.Mussels

    • a.Attach to firm substrates with BYSSUS THREADS

    • b.Mytilus edulis

    • (1)Edible mussel

    • (2)Defend themselves by pinning predatory snails with byssus threads


    06 benthos

    Littorina, Marsh Periwinkle

    Geukensia Ribbed Mussel

    (Bivalve)

    Lippson & Lippson, 1984, Life in the Chesapeake,p. 162


    06 benthos

    • Bivalves (continued)

    • 4.Oysters

    • a.Attach with cement

    • b.Mantle secretes cement around attached valve

    • c.Smaller valve remains free


    06 benthos

    Oyster Drill

    Oyster, Crassostrea, and Associated Mollusks

    Lippson & Lippson, 1984, Life in the Chesapeake,p. 123


    06 benthos

    Mobile Press Register March 9, 2008


    06 benthos

    Mobile Press Register March 9, 2008


    06 benthos

    • Bivalves (continued)

    • 5.Shipworms

    • a.Bivalves that burrow into submerged wood

    • b.Repeated movement of rough valves erodes cavity

    • c.Destroy wharves


    06 benthos

    Inhalent & exhalent siphons

    Shell

    Shipworm removed from tunnel

    http://web.forestry.ubc.ca/fetch21/FRST308/lab8/bankia_setacea/bankia%20wormA1_1.JPG


    06 benthos

    Wood damaged by shipworms

    http://web.forestry.ubc.ca/fetch21/FRST308/lab8/bankia_setacea/Bankia%20in%20galB1_1.JPG


    06 benthos

    • Bivalves (continued)

    • 6.Tridacna

    • a.“Man-eating” clam

    • b.Harbor colorful zooxanthellae

    • (= symbiotic dinoflagellates)

    • c. Biggest bivalve on tropical reefs


    06 benthos

    Tridacna, the “Man-eating” Clam


    06 benthos

    Tridacna, with colorful Zooxanthellae


  • Login