Unit 2
Lecture 11:
Phylum Rotifera
- Wheel bearers
- 1mm > in size
- Ciliated crown = Corona
- Pumping pharynx - Mastax
- Body forms indicative of life style
- Floating planktonic = globular
- Swimmers/creepers = wormlike
- Sessile = vase-like
- Colonial
Phylum Acanthocephala
- Spine-head
- Retractable introverted spiny proboscis* (long mobile nose)
- All parasitic invertebrate
- Intermediate host (crustacean)
- Absorb nutrients through epidermis (no digestive tract)
- Attaches to intestinal wall
Phylum Chordata
- Bilateral symmetry
- Anteroposterior axis
- Coelom
- “Tube within a tube” body plan
- Metamerism
- Cephalization
Phylum Ectoprocta
- Anus outside
- Bryozoa (moss animal)
- Colonial in zoecium chamber
- Feeding forms, some polymorphism
- Invasive and fouling
- Medical compounds
- Bryostatin cancer-fighting
Phylum Nemertea
, - Ribbon or proboscis worms
- Terrestrial and marine
- Proboscis and rhynchocoel cavity
- Mesodermal cavity = coelom
- 60cm> in length
- Carnivorous
Phylum Nematoda
- 80% of all life on earth
- free-living, parasitic
- Slender (tube within tube)
- Pseudocoelomates
- Hydrostatic skeletons, only longitudinal muscles
- Collagenous cuticle
- Dioecious, internal fertilzation reproduction
- Muscular pharynx
Nematode parasites
- Ecto- and endoparasites
- Doesn’t need intermediate ost
- Cuticle = defense
- Adapted mouthparts
- Reproduction
Ex. Intestinal roundworm, hookworms, filarial worms, pinworms
Phylum Nematomorpha
- Semi-parasitic
- Adults free-living
- Parasitic in arthropods as juveniles
- 1m> long
Ex. Horsehair worms
Phylum Onychophora
- Velvet worms
- Leafy habitats
- Unjointed legs
Phylum Tardigrada
- 8 unjointed legs
- Sucking pharynx
- Marine, freshwater, damp terrestrial
, - Cryptobiosis
Phylum Hemichordata
- “Half chordates”
- Gill slits and notochord
- Gill slits in all duterostomes
- Three-part coelom common of deuterostomes
Phylum Arthropoda
- Inverts with segmented bodies, joint limbs and exoskeleton
- Exoskeleton made of chitinous cuticle, protection and mobility
- Segmentation and appendages have specialized functions; locomotion
- All habitats
- Respiration -> metabolism
- Breathe water/air
- Sense organs
- Eyes
- Hearing
- Balance
- chemosensory
- Complex behaviour
- Metamorphosis
- All individuals of the same species exploit environmental niches without
competition
- More niches available
Diverse because
1. Exoskeleton
2. segmentation/appendages
3. Various habitats
4. Respiration -> metabolism
5. Sense organs
Phylum Echinodermata
- Marine, mostly benthic (bottom)
- Lack cephalization
- Features:
- Calcareous endoskeleton
- Water vascular system
- Pedicelariae
- Dermal branchaie
, - Pentaradial symmetry in adults
Echinoderm characteristics---------------------
1. Endoskeleton
● Mesodermal endoskeleton
○ Ossicles (calcareous plates) connected by collagen. “Catch
collagen” liquid to solid.
○ Help hold a shape without using energy and is strong
● Part of a unique coelom called the stereom
2. Water-vascular system
● Hydraulic system
Canals and tube feet (to keep in place)
Tube feet are thin-walled so can be used for respiration,
chemoreception and metabolic excretion
● Functions: respiration, excretion, locomotion and feeding*
● Series of canals (in order)
1. Madreporite
2. Stone canal
3. Ring canal
4. Radial canal
5. Ampullae
6. Podia (tube feet)
3. Pedicellariae
● On aboral surface
● Often found at the base of spine
Lecture 11:
Phylum Rotifera
- Wheel bearers
- 1mm > in size
- Ciliated crown = Corona
- Pumping pharynx - Mastax
- Body forms indicative of life style
- Floating planktonic = globular
- Swimmers/creepers = wormlike
- Sessile = vase-like
- Colonial
Phylum Acanthocephala
- Spine-head
- Retractable introverted spiny proboscis* (long mobile nose)
- All parasitic invertebrate
- Intermediate host (crustacean)
- Absorb nutrients through epidermis (no digestive tract)
- Attaches to intestinal wall
Phylum Chordata
- Bilateral symmetry
- Anteroposterior axis
- Coelom
- “Tube within a tube” body plan
- Metamerism
- Cephalization
Phylum Ectoprocta
- Anus outside
- Bryozoa (moss animal)
- Colonial in zoecium chamber
- Feeding forms, some polymorphism
- Invasive and fouling
- Medical compounds
- Bryostatin cancer-fighting
Phylum Nemertea
, - Ribbon or proboscis worms
- Terrestrial and marine
- Proboscis and rhynchocoel cavity
- Mesodermal cavity = coelom
- 60cm> in length
- Carnivorous
Phylum Nematoda
- 80% of all life on earth
- free-living, parasitic
- Slender (tube within tube)
- Pseudocoelomates
- Hydrostatic skeletons, only longitudinal muscles
- Collagenous cuticle
- Dioecious, internal fertilzation reproduction
- Muscular pharynx
Nematode parasites
- Ecto- and endoparasites
- Doesn’t need intermediate ost
- Cuticle = defense
- Adapted mouthparts
- Reproduction
Ex. Intestinal roundworm, hookworms, filarial worms, pinworms
Phylum Nematomorpha
- Semi-parasitic
- Adults free-living
- Parasitic in arthropods as juveniles
- 1m> long
Ex. Horsehair worms
Phylum Onychophora
- Velvet worms
- Leafy habitats
- Unjointed legs
Phylum Tardigrada
- 8 unjointed legs
- Sucking pharynx
- Marine, freshwater, damp terrestrial
, - Cryptobiosis
Phylum Hemichordata
- “Half chordates”
- Gill slits and notochord
- Gill slits in all duterostomes
- Three-part coelom common of deuterostomes
Phylum Arthropoda
- Inverts with segmented bodies, joint limbs and exoskeleton
- Exoskeleton made of chitinous cuticle, protection and mobility
- Segmentation and appendages have specialized functions; locomotion
- All habitats
- Respiration -> metabolism
- Breathe water/air
- Sense organs
- Eyes
- Hearing
- Balance
- chemosensory
- Complex behaviour
- Metamorphosis
- All individuals of the same species exploit environmental niches without
competition
- More niches available
Diverse because
1. Exoskeleton
2. segmentation/appendages
3. Various habitats
4. Respiration -> metabolism
5. Sense organs
Phylum Echinodermata
- Marine, mostly benthic (bottom)
- Lack cephalization
- Features:
- Calcareous endoskeleton
- Water vascular system
- Pedicelariae
- Dermal branchaie
, - Pentaradial symmetry in adults
Echinoderm characteristics---------------------
1. Endoskeleton
● Mesodermal endoskeleton
○ Ossicles (calcareous plates) connected by collagen. “Catch
collagen” liquid to solid.
○ Help hold a shape without using energy and is strong
● Part of a unique coelom called the stereom
2. Water-vascular system
● Hydraulic system
Canals and tube feet (to keep in place)
Tube feet are thin-walled so can be used for respiration,
chemoreception and metabolic excretion
● Functions: respiration, excretion, locomotion and feeding*
● Series of canals (in order)
1. Madreporite
2. Stone canal
3. Ring canal
4. Radial canal
5. Ampullae
6. Podia (tube feet)
3. Pedicellariae
● On aboral surface
● Often found at the base of spine
