acrobeles complexus ch 11 pseudocoelomates ch 11 pseudocoelomates “soo-doe-see-low-mates”
TRANSCRIPT
![Page 1: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/1.jpg)
Acrobeles complexus
Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”
![Page 2: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/2.jpg)
![Page 3: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/3.jpg)
![Page 4: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/4.jpg)
PseudocoelomatesPseudocoelomates• 9 phyla:
– Rotifera- do not molt (Lophotrochozoan)
– Acanthocephala
– Nematoda molt (Ecdysozoan)– Nematomorpha
– Kinoryncha
– Loricifera
– Priapulida
– Gastrotrichia
– Entoprocta
![Page 5: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/5.jpg)
PseudocoelomatesPseudocoelomates
Plant ectoparasite
A. lumbricoides
• 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
![Page 6: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/6.jpg)
PseudocoelomatesPseudocoelomates
• Common characteristics: 1. Pseudocoelom
2. Eutely
3. complete digestive tract (mouth and anus)
Acanthocephalans and nematomorphs do not have a complete digestive tract
![Page 7: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/7.jpg)
Common characteristics: 1) 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
![Page 8: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/8.jpg)
Common characteristics: 1) Pseudocoelom
• No muscular tissue associated with gut tract
• No membranes suspend organs in body cavity
![Page 9: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/9.jpg)
• Pseudocoelom is spacious, fluid-filled– Contains visceral organs
– Forms hydrostatic skeleton
![Page 10: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/10.jpg)
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
![Page 11: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/11.jpg)
Common characteristics:
2) Eutely
• Body composed of constant number of somatic cells (or nuclei) in adults
![Page 12: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/12.jpg)
http://www.wormatlas.org/handbook/alimentary/alimentary2.htm
Common characteristics: 3) complete digestive tract (mouth and
anus)
• Most other higher animals
![Page 13: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/13.jpg)
Do these questions Do these questions now…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?
![Page 14: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/14.jpg)
• Organ systems present:– Digestive system
– Excretory system
– Nervous system
– Reproductive system
• Organ systems absent:– Circulatory system
– Respiratory system
PseudocoelomatesPseudocoelomates
![Page 15: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/15.jpg)
Phylum NematodaPhylum Nematoda
The roundworms
![Page 16: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/16.jpg)
Phylum NematodaPhylum Nematoda
• 12,000 species– 500,000 possible
• Cylindrical body
• Mostly dioecious
• Only longitudinal muscles
– Undulate/thrash around (don’t crawl) movie
![Page 17: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/17.jpg)
Phylum NematodaPhylum Nematoda
• Noncellular cuticle with several layers– Maintains internal hydrostatic pressure
– Provides mechanical protection
– Resists digestion by host (in parasitic nematodes)
![Page 18: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/18.jpg)
Phylum Nematoda Phylum Nematoda (cont’d)(cont’d)
• Found everywhere– Oceans
– Polar ice
– Hot springs
– soil
![Page 19: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/19.jpg)
5 billion per acre
![Page 20: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/20.jpg)
Phylum Nematoda Phylum Nematoda (cont’d)(cont’d)
• Eat just about every type of organic material– Rotting
substance
– Living tissue
• Parasites of nearly all plant and animal species!
![Page 21: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/21.jpg)
Ascaris lumbricoidesAscaris 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
![Page 22: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/22.jpg)
PinwormsPinworms
• Most common parasite in US
• 30% children; 16% adults
• Large intestine
• Lay eggs in anus at night
• Spread– Fecal oral route
![Page 23: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/23.jpg)
Filarial WormsFilarial Worms
• “Elephantiatis”
• 250 million people (tropics)
• Lives in lymphatic system
• Obstruct lymph to cause swelling
Microfilaria of Wuchereria bancrofti
![Page 24: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/24.jpg)
Other parasitic Other parasitic nematodesnematodes
• Hookworms
• Dog heartworms
• Trichinella (causes trichinosis)
![Page 25: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/25.jpg)
• biomedical research– C. elegans
![Page 26: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/26.jpg)
C. elegansC. elegans
• Free living nematode
• 959 cells– Development of
every cell is known (movie)
• Genome sequenced– NCBI
![Page 27: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/27.jpg)
http://www.nobel.se/medicine/laureates/2002/press.html
Sydney Brenner- C. elegans since 1963
• C. elegans
• Nobel Prize (2002)Brenner, Sulston and Horvitz– “Genetic regulation of
organ development and programmed cell death”
![Page 29: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/29.jpg)
Phylum RotiferaPhylum Rotifera
http://www.microscopyu.com/galleries/dxm1200/images/collothecalarge.jpg
– rota= wheel
– fera= bearer
• Ciliated crown (corona)– (movie)
![Page 30: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/30.jpg)
Phylum RotiferaPhylum Rotifera
http://micro.magnet.fsu.edu/primer/techniques/phasegallery/images/rotifer.jpg
• Mostly microscopic
• 1800 species
• Many resistant to desiccation
• dioecious
![Page 31: Acrobeles complexus Ch 11 Pseudocoelomates Ch 11 Pseudocoelomates “soo-doe-see-low-mates”](https://reader031.vdocuments.site/reader031/viewer/2022033108/56649cf95503460f949cb215/html5/thumbnails/31.jpg)
Phylum RotiferaPhylum Rotifera
Internal Anatomy of a Typical Rotifer
• Aquatic (mostly freshwater)– Protonephridia with flame
cells