Midterm 1 - Lifestyle of invertebrates

what are the 6 feeding strategies

suspension feeders

detritivores

deposit feeders

herbivores

carnivores

symbiotic feeders

how do suspension feeders eat, and an example of a suspension feeder

they capture particles suspended in water. ex: larvaceans

how do detritivores eat, and an example of a detritivore

feed on fallen organic material. ex: abalone, and fiddler crabs

how do deposit feeders eat, and an example of a deposit feeder

they consume sediment and can be either selective - feeding on the sediment surface, or nonselective - feeding within the sediment (bulk feeders). ex: sea cucmbers

how do symbiotic feeders eat, and an example of a symbiotic feeder

two species that build a nutritional relationship over time. ex: hard corals and photosynthetic symbionts

3 types of carnivores

1. grazing: eat sessile animals

2. predators: pursue prey

3. scavengers: feed on dead organisms

explain why terrestrial animals have internal respiratory structures and aquatic animals have external respiratory structures

terrestrial animal’s structures are internal because they must be protected from water loss. Aquatic animals have external structures because water has a low concentration of oxygen, so external structures maximize the contact with moving water to capture oxygen.

compare reproduction in terrestrial and aquatic animals

Terrestrial: internal fertilization because gametes would dry out if released externally, greater nutrient investment per egg, fewer larger eggs produced

Aquatic: external fertilization because gametes are protected from becoming dried out, less nutrient investment per egg, many small eggs produced

compare excretion in terrestrial and aquatic animals

Terrestrial: toxic ammonia is converted into urea/uric acid so that it can be stored

Aquatic: ammonia is diluted from the constant flow of water and released into the surrounding water

what are the three types of motility

1. Sessile: permanently attached, lives in one place

2. Sedentary: remains in one area but not permanently attached, can move occasionally

3. Motile: regularly moves and can travel significant distances

Ontogenetic transition and an example

lifestyle changes during development. ex: bivalvs have motile larval stage and sessile / sedentary adult stage

3 examples of sessile animals

sponges, hard corals, sea anemonies

2 examples of sedentary animals

feather duster worms, sea scallops

3 examples of motile animals

sea stars, octopus, nautilus

What are the 2 different aquatic habitats

1. Benthic: living on/in the bottom floor

2. Pelagic: living in the water column

what are the two types of benthic habitats

1. Epibenthic: on the surface

2. Infaunal: in the substrate

what are the two types of pelagic habitats

1. Planktonic: drift with the current

2. Nektonic: active swimmers