Zoology Lab 3 Flashcards
Phylum Rotifera : Key traits
- They have a true alimentary canal with a mouth and anus.
- Have a set of jaws called the mastax.
- The body can be differentiated in 3 regions : head, trunk and foot.
- Have a large corona on the anterior end.
Phylum Nematoda : Key traits
- Within the clade Ecdysozoa
- Undergo a process of ecdysis of their cuticle
- called Roundworms.
- Most free living and some important parasites of plants.
Nematode sexual reproduction
- Have separate sexes ( dioecious)
- Female are larger than males
- The posterior end of the male is sharply curve.
Identify the missing parts
Clade?
Phylum ?
Try to identify the structures. (corona, pharynx, mastax, stomach)
Lophotrochozoa
Phylum Rotifera
Phylum ?
Clade?
Name of slide?
Is there a layer of muscle tissue adjacent to the gut?
Male or female?
Phylum : Nematoda
Clade : Ecdysozoa
Ascaris cross section
Yes, muscle just underneath epidermis.
Male
Male or female ?
Clade ?
Phylum ?
Female
Ecdysozoa
phylum = nematoda
How do nematodes move?
- Nematodes use the fluid in their pseudocoelom as a hydrostatic skeleton that allow movement.
- As one set of muscles contracts, the opposing group must expand to accomodate the fluid.
Name
Phylum ?
Clade?
Vinegar eel ( Anguillula aceti)
Phylum: Nematoda
Clade : Ecdysozoa
Phylum ?
Clade?
Lifestyle ? (herbivore or bacterivore)
Ancylostoma duodenale
Phylum : Nematoda
Clade: Ecdysozoa
Bacterivore
Phylum ?
clade ?
Lifestyle ?
Vinegar eel
Phylum: Nematoda
Clade : Ecdysozoa
Herbivore
Name ?
Phylum?
Clade?
Class?
Earthworm
Phylum = Annelida
Clade = Lophotrochozoa
Class : Oligochaeata
Observe the mouth, pharynx , crop and gizzard.
Name of slide ?
Clade
Phylum ?
Class?
Cross-section of an earthworm
Clade : Lophotrochozoa
class : Oligochaeta
Phylum : Annelida
How many tissues layer?
Det. which type of body cavity
Any support structures ?
They are triploblastic
Body cavity = coelomate
support structures = coelomic fluid acts as hydrostatic skeleton
Phylum?
Clade?
Class?
Phylum : Annelida
Clade: Lophotrochozoa
Class : Hirudinea
Leeches have what kind of reproduction ?
They are monoecious
Clade?
Phylum ?
Class?
Are members aquatic, terrestrial or both ?
Clade = Lophotrochozoa
Phylum = Annelida
Class= Polychaeta
They are aquatic and almost all species are marine dwelling.
Class ? What does the class signifies ?
Polychaeta
It means that they have many chaetae.
Male anatomy
Ascaris morphology
Female cross-section
Ascaris
What does parapodia means ?
Where do you find this strucuture in ?
- They are chaetae that have a paddle like structure which occurs at the side of the body.
- You find this structure in the clade lophotrochozoa, phylum annelida and class polychaeta
What is the function of the thin cuticle layer on the outside of the earthworm?
It helps retain the water.
What is the name of the bristles on the underside of the earthworm?
what does oligo stand for ?
Chaeta or setae
oligo = few
The muscular arrangement of annelids
- Body wall contain longitudinal & circular muscle for burrowing and swimming.
- Movement is by their circular muscles which expand and contract, moving the animal forward as well as side to side.
What kind of muscle does nematodes have ?
- Just inside their gut are the longitudinal muscles; unlike other worms (annelids), the nematodes lack a circular muscle and so their movement is restricted to a side-to-side whip.
What is the main difference between the phylum nematoda and annelida ?
- So basically the main difference in the two phylum is the presence or lack of circular muscle which is an important evolutionary step in annelids as it allows more effective movement
What is the most distinguishing feature of the phylum annelida ?
- The most distinguishing feature of this group is segmentation, with the segments visible as rings around the body.
What kind of predators are the leeches(class hirudinea) ?
Most are scavengers or predators of small invertebrates and some are blood feeding species.
Where do leeches live ?
Most live in freshwater environements but there are also marine and terrestrial species.
What is the most prominent feature of the class hirudinea ?
Is the presence of a large posterior sucker that aids in attachment for blood-feeding species but also serves other purposes.
What are the similarities of leech to the other annelids ?
The leech does have segements though the segments are not seen.
And they do lack parapodia like the oligochaetes.
Why is the anterior sucker smaller than the posterior sucker in leeches ?
Anterior suckers = use mainly as a feeding structure
Posterior sucker = for locomotion
What are the feature that are specific to parasitic leeches ?
They have anticoagulant
