Transcript coelomates - protostomes

I. Coelomate Animals
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A. Have a true coelom, not a pseudocoelom
B. True coelom is a hollowed out space inside the
mesoderm, not a space between tissue layers
C. Coelom provides space for organs to develop
II. Gastrulation =
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Formation of gastrula.
A) Indentation creates opening called blastopore
B) Blastopore either becomes mouth or anus
C) Protostome = blastopore becomes mouth
D) Deuterostome = blastopore becomes anus
III. Groups of Animals have
Coeloms (Coelomates)
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Protostomes
mouth forms first
Phylum Mollusca
Phylum Annelida
Phylum Arthropoda
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Deuterostomes
anus forms first
Phylum Echinodermata
Phylum Chordata
IV. Traits of All Coelomates
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A) multicellular
B) true tissues
C) bilaterally symmetrical
D) triploblastic
E) have alimentary canal (complete digestive system)
F) have a coelom
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Draw a phylogenetic tree including
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Porifera, flatworms, round worms, rotifers, proterospongia,
coleolmates, cnidarian,
Phylum Mollusca = mollusks
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Respiration by gills, lung or diffusion
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All have hearts & open circulatory systems
Blood leaves heart in an artery
 Blood flows out the open ends of the artery to
circulate directly through tissues and sinuses
 Blood funneled
back to heart
to be pumped again
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Specialized Mollusk Traits
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Mantle :membrane covering that may secrete a shell
Radula = feeding structure that may be like a file, a
drill or a beak
https://www.youtube.com/watch?v=cEMK3VN8pW8 https://www.youtube.com/watch?v=2BsYejyH8e0
https://www.youtube.com/watch?v=tfMY0fW8UwE
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Muscular Foot = used for locomotion
Class Bivalvia
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Name means 2 shells
Most are filter feeders
Clams, oysters, mussels,
scalops
Class Gastropoda
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Name means Stomach-Foot
snails, slugs & nudibranchs (sea slugs)
Class Cephalopoda
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Name means head-foot
Squids, octopuses, nautiluses, cuttlefish
Giant Squid!
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Largest invertebrate
Up to 60 ft long
This one was a young
female 24 ft long
The first live giant squid
ever captured
Large size made
possible by myalinated
nerves and closed
circulatory system
http://shapeoflife.org/vi
deo/molluscs-survival-
Cephalopod Derived Traits :
Adaptations of a Predator
Shell filled with chambers of air for buoyancy
 Shells lost or small & internal = less weight
 Closed circulatory system = faster circulation
for better delivery of oxygen to muscles
 Well developed eyes and brain = must be
smarter than the food
 Foot converted to tentacles
and siphon (jet propulsion)
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Phylum Annelida:Segmented worms
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Earth worms
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Marine Worms
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Leeches
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Freshwater
worms
Annelid traits
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Body divided into segments
Respiration by diffusion or gills
(skin must be damp to breath by diffusion)
Excretion by true nephridia in each segment
Alimentary canal
Closed circulatory system
(blood always in vessels or heart)
Ganglia with ventral nerve cords
http://www.npr.org/player/v2/mediaPlayer.html?action=1&t=1&islist=false&id=9105956&m=9105957
http://shapeoflife.org/video/annelids-powerful-and-capable-worms
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Worm Specialized Digestive organs:
1) pharynx: sucks in/swallows food
2) Esophagus: pushes food to crop
3) Crop: stores food
4) Gizzard: grinds food
5) Intestine: absorbs nutrients
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Circulatory System
1) aortic arches: pump blood (5 ‘hearts’)
2) dorsal blood vessel: brings blood to arches
3) ventral blood vessel: carries blood from arches
4) smaller blood vessels: branch off 2 & 3
4) capillary beds: deliver nutrients connect 2 & 3
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Hydrostatic skeleton:
Muscles pull against water filled body cavity
coelomic fluid
Circular muscles: elongate segment
Longitudinal muscles: shorten segment
Setae (bristles): anchor worm
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Reproduction:
Sexual only
Hermaphrodites: produce both egg and sperm
then trade 
Clitellum: forms cocoon for fertilized eggs
Internal fertilization: eggs fertilized inside cocoon
Phylum Arthropoda
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Subphylum Crustacea
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Class Arachnida
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Class Insecta
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Classes
Diplopoda/chilopoda
Arthropod Traits
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Name means jointed-foot
Also have jointed legs
Segmented bodies
Exoskeleton
Open circulatory system
Ganglia fused into simple brain
ventral nerve cords
Complete digestive system
Insect Innovations
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Respiration using tracheae –tubes that branch
throughout the body
Compound eye
Wings
Complex life cycle
Arachnids
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Respiration by book lungs
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spiders
ticks
mites
Scorpions
harvestmen
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May have silk glands to make web
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Crustacea
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Nearly all aquatic
Respiration by gills
Important part of zooplankton