ch 11 pseudocoelomates soo doe see low mates l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Ch 11 Pseudocoelomates “soo-doe-see-low-mates” PowerPoint Presentation
Download Presentation
Ch 11 Pseudocoelomates “soo-doe-see-low-mates”

Loading in 2 Seconds...

play fullscreen
1 / 31

Ch 11 Pseudocoelomates “soo-doe-see-low-mates” - PowerPoint PPT Presentation


  • 185 Views
  • Uploaded on

Acrobeles complexus. Ch 11 Pseudocoelomates “soo-doe-see-low-mates”. Pseudocoelomates. 9 phyla: Rotifera- do not molt (Lophotrochozoan) Acanthocephala Nematoda molt (Ecdysozoan) Nematomorpha Kinoryncha Loricifera Priapulida Gastrotrichia Entoprocta. Plant ectoparasite.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Ch 11 Pseudocoelomates “soo-doe-see-low-mates”' - hayden


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
pseudocoelomates
Pseudocoelomates
  • 9 phyla:
    • Rotifera- do not molt (Lophotrochozoan)
    • Acanthocephala
    • Nematoda molt (Ecdysozoan)
    • Nematomorpha
    • Kinoryncha
    • Loricifera
    • Priapulida
    • Gastrotrichia
    • Entoprocta
pseudocoelomates5

Plant ectoparasite

A. lumbricoides

Pseudocoelomates
  • A heterogeneous group:
    • Size: microscopic  several meters
    • some are exclusively marine; some (e.g., nematodes) live in a variety of habitats, esp. soil); and some are exclusively parasitic

pinworms

pseudocoelomates6
Pseudocoelomates
  • Common characteristics:
    • Pseudocoelom
    • Eutely
    • complete digestive tract (mouth and anus)

Acanthocephalans and nematomorphs do not have a complete digestive tract

slide7
Common characteristics:
  • Pseudocoelom
    • body cavity (pseudocoelom/ pseudocoel)
    • a space b/w gut and mesodermal components of body wall
    • Body cavity is not lined with a mesodermal sheet
      • Does not cover inner surface of body wall
slide8
Common characteristics:
  • Pseudocoelom
    • No muscular tissue associated with gut tract
    • No membranes suspend organs in body cavity
slide9
Pseudocoelom is spacious, fluid-filled
    • Contains visceral organs
    • Forms hydrostatic skeleton
slide10
Evolutionary advantages of pseudocoel:
  • Greater freedom of movement
  • Space for development and differentiation of organ systems (ie. digestive, excretory)
    • differentiation: process by which cells become different, specialized
  • Simple means of circulation/distribution of materials throughout body
  • Storage place for waste products to be discharged to outside
  • Hydrostatic skeleton
    • Fluid enclosed by muscular wall  support
slide11
Common characteristics:
  • Eutely
    • Body composed of constant number of somatic cells (or nuclei) in adults
slide12

http://www.wormatlas.org/handbook/alimentary/alimentary2.htm

Common characteristics:

  • complete digestive tract (mouth and anus)
    • Most other higher animals
do these questions now
Do these questions now…
  • What type of germ layer lines the pseudocoelom in nematode embryos?
  • What organ systems are present/absent in pseudocoelomates
  • What are the advantages of having a pseudocoelom vs. no coelom?
pseudocoelomates14
Pseudocoelomates
  • Organ systems present:
    • Digestive system
    • Excretory system
    • Nervous system
    • Reproductive system
  • Organ systems absent:
    • Circulatory system
    • Respiratory system
phylum nematoda

Phylum Nematoda

The roundworms

phylum nematoda16
Phylum Nematoda
  • 12,000 species
    • 500,000 possible
  • Cylindrical body
  • Mostly dioecious
  • Only longitudinal muscles
    • Undulate/thrash around (don’t crawl) movie
phylum nematoda17
Phylum Nematoda
  • Noncellular cuticle with several layers
    • Maintains internal hydrostatic pressure
    • Provides mechanical protection
    • Resists digestion by host (in parasitic nematodes)
phylum nematoda cont d
Phylum Nematoda (cont’d)
  • Found everywhere
    • Oceans
    • Polar ice
    • Hot springs
    • soil
phylum nematoda cont d20
Phylum Nematoda (cont’d)
  • Eat just about every type of organic material
    • Rotting substance
    • Living tissue
  • Parasites of nearly all plant and animal species!
ascaris lumbricoides
Ascaris lumbricoides
  • Human parasite
    • Up to 30cm long
  • 1.2 billion people
    • Many in southeast US
  • Females lay 200,000 eggs a day
  • Unsanitary habits contaminate ground
    • Ingest eggs
    • Hatch  bury into veins  lungs  pharynx
    • Swallowed  intestine
pinworms
Pinworms
  • Most common parasite in US
  • 30% children; 16% adults
  • Large intestine
  • Lay eggs in anus at night
  • Spread
    • Fecal oral route
filarial worms

Microfilaria of Wuchereria bancrofti

Filarial Worms
  • “Elephantiatis”
  • 250 million people (tropics)
  • Lives in lymphatic system
  • Obstruct lymph to cause swelling
other parasitic nematodes
Other parasitic nematodes
  • Hookworms
  • Dog heartworms
  • Trichinella (causes trichinosis)
c elegans
C. elegans
  • Free living nematode
  • 959 cells
    • Development of every cell is known (movie)
  • Genome sequenced
    • NCBI
slide27

Sydney Brenner

    • - C. elegans since 1963
  • C. elegans
  • Nobel Prize (2002)Brenner, Sulston and Horvitz
    • “Genetic regulation of organ development and programmed cell death”

http://www.nobel.se/medicine/laureates/2002/press.html

phylum rotifera29

http://www.microscopyu.com/galleries/dxm1200/images/collothecalarge.jpghttp://www.microscopyu.com/galleries/dxm1200/images/collothecalarge.jpg

Phylum Rotifera
    • rota= wheel
    • fera= bearer
  • Ciliated crown (corona)
    • (movie)
phylum rotifera30

http://micro.magnet.fsu.edu/primer/techniques/phasegallery/images/rotifer.jpghttp://micro.magnet.fsu.edu/primer/techniques/phasegallery/images/rotifer.jpg

Phylum Rotifera
  • Mostly microscopic
  • 1800 species
  • Many resistant to desiccation
  • dioecious
phylum rotifera31
Phylum Rotifera
  • Aquatic (mostly freshwater)
    • Protonephridia with flame cells

Internal Anatomy of a Typical Rotifer