Lecture 5 - Feeding II Flashcards
What do barnacles use to feed?
Cirri
What features are contained in the generalised mollusc structure
poorly defined head, foot, shell
What do macrophages browsers eat
microscopic algae via a radula
What is a radula and how does it work
Ribbon of chitinous teeth. It can be projected out of the mouth. Moves like a conveyor belt over odontophore. Teeth scrape surface and then food is moved back into the buccal cavity.
What is the dental formula for Gastropods?
- Demonstrate all major feeding types
- Radula:
- one central tooth (rachis) (1)
- One or more lateral teeth (2)
- One or more marginal teeth (4)
- Dental formula – 4 + 2 + 1 + 2 + 4
Generalised mollusc features?
Benthic
Poorly defined head
Foot
Shell
What do Microphagous browsers feed on?
Microscopic
algae
Gougers example and radula features?
e.g. limpets
Docoglossate (spear) radula
Iron and silicon
Scrapers/sweepers example and radula features
e.g. abalone
Rhipidoglossate (fan) radula
drillers example and radula features
Carnivores
e.g. whelk, Thais
Rachiglossate (spine) radula
3 large, multicusped teeth
What do bivalves use to feed?
Lamellibranch gills (ctenidia)
What does the stomach of bivalves contain?
crystalline style
what is the function of the Pyloric caeca?
Additional digestion
How do filter feeding brittle stars feed?
Trap food with mucous strings
Wipe arms on spines
How do Carnivores brittle stars feed?
Five jaws, stomach is blind sac
Arms lasso prey
food, feeding structure and strategy of sea urchins?
Algae grazers
Aristotle’s lantern with teeth
Scrape, grasp and pull food
how do sea cucumbers feed?
Deposit feeders and filter feeders Buccal podia (tentacles) stuff deposit into mouth
What is the diet and feeding structures of a horseshoe crab?
Benthic omnivores Food groove Gnathobases crush food Proventriculus Gizzard and storage
What is the function of Chelicerae?
immobilise prey
What are Chelipeds?
pincers or claws
key features of decapod mouth?
Buccal frame
Chelipeds – pincers or claws
Mandibles and five pairs of appendages (maxillipeds
and maxillae)
how does predation work in decapods?
Food captured with chelipeds
Passed to 3rd maxillipeds
Pieces torn by maxillae and
maxillipeds
how does deposit feeding work in decapods?
Chelipeds scoop up mud and detritus
Water from branchial chamber washes sediment
through setal filters
Organic particles are ingested
What do barnacles use to feed?
cirri
What are the key insect mouthparts?
Labrum – ‘upper lip’
Mandibles
Maxillae
Labium – ‘lower lip’
how are the mouthparts modified in piercing and sucking insects?
Beak with piercing stylet
and covering labium
Salivary and food channels
What do insects specialising in sucking tend to have?
Highly modified maxillae
