Lab 6 Flashcards
Describe phylum Annelida
Worm like body divided both externally and internally. Anterior segments unite to form a head. Body wall has a thin cuticle, epidermis, and two layers of muscle. Annelids may also be covered in bristle-like setae. They have a large coelom divided by septa
Annelids are said to be “metameric”. What does this mean?
Annelids are divided into segments that are more or less similar in function
What is the phylum, class, genus, and species of this organism? What are the common features of this class? What sensory structures does this organism have?
What is the purpose of structure A?
Describe the feeding habits of this organism
Phylum - Annelida
Class - Polychaeta
Genus - Nereis
Species - virens
Have parapodia (fleshy appendage-like outgrowths of the body wall), distinct head with sensory organs, and many body segments.
Nereis has eyes, tentacles, and sensory palps.
Structure A is Parapodia, used for gas exchange or locomotion.
Jaws kept inside of pharynx, which is protruded to eat food. These organisms hide in sediments and burst forth to catch prey.
What is the phylum, class, and genus of this organism? Where are the setae? What purpose do you suppose the parapodia serve?
Phylum - Annelida
Class - Polychaeta
Genus - Aphrodita
Setae are arranged in a gross mat over the dorsal surface of the organism
The parapodia probably are used in movement.
What are the primary characteristics of class Clitellata of the Annelids?
Hermaphroditic, have a clitellum. No head appendages or parapodia
What is the phylum, class, subclass, genus and species of this organism? What is structure A? How does one located the head on this organism? Where are the setae?
Phylum - Annelida
Class - Clitellata
Subclass - Oligochaeta
Genus- Lumbricus
Species - terrestris
A is the clitellum - hermaphroditic reproductive structure
Head is closer to clitellum. Setae are located on the ventral surface to aid in locomotion.
Name the highlighted structures in this Earthworm cross section
1 - Cuticle
2 - Epidermis
3 - Circular muscles
4 - Longitudinal muscles
6 - Setae
Name the phylum, class, subclass, genus and species of this organism. What is the common name for this organism?
There are only 33 body segments, so why does it appear otherwise externally? Where is the mouth located?
Phylum - Annelida
Class - Clitellata
Subclass - Hirudinea
Genus - Hirudo
Species - medicinalis
AKA medical leech
Extra annuli develop superficially, giving the appearance of more segments. The head is closest to the small sucker (anterior)
What are the structures labelled “A” in this cross section of the medical leech?
Blood sinuses
What makes the phylum Onychophora so unique?
They are unique because they are like a middle ground between Annelida and Arthropoda. They are worm-like with many short walking legs (true legs), and a distint head bearing mandibles, oral papillae and antennae. The appendages are non-jointed and they have unspecialized smooth muscle, much like annelids. However, like arthropods, they have a thin chitinous cuticle (exoskeleton) and a hemocoel body cavity with open circulation
What is the phylum and genus of this organism? Identify structures A and B. This organism is covered in ______. Describe its feeding habits
Phylum - Onychophora
Genus - Peripatus
A - Antennae (there’s 1 pair)
B - Legs (non-jointed)
Covered in papillae.
Peripatus catches prey by ejecting a sticky glue from its antennae. Then it pokes a hole in the exoskeleton of the prey using its mandibles.
What is the meaning of the term “hemocoel”?
Primary body cavity of arthropods, used as a circulatory system
