Exam 33: An Introduction to Invertebrates

A brachiopod can be distinguished from a bivalve by the presence of

Which mollusc clade includes members that undergo embryonic torsion?

Use the following information to answer the questions below. Nudibranchs, a type of predatory sea slug, can have various protuberances (i.e., extensions) on their dorsal surfaces. Rhinophores are paired structures, located close to the head, which bear many chemoreceptors. Dorsal plummules, usually located posteriorly, perform respiratory gas exchange. Cerata usually cover much of the dorsal surface and contain nematocysts at their tips. -The feet of certain insects, notably of female butterflies, have a function most similar to that of

Use the following information to answer the questions below. This nudibranch, a type of sea slug, has many reddish cerata on its dorsal surface, as well as two, white-tipped rhinophores located on the head. The nontaxonomic term sea slug encompasses a wide variety of marine gastropods. One feature they share as adults is the lack of a shell. We might think, therefore, that they represent defenceless morsels for predators. In fact, sea slugs have multiple defences. Some sea slugs prey on sponges and concentrate sponge toxins in their tissues. Others feed on cnidarians, digesting everything except the nematocysts, which they then transfer to their own skins. Whereas the most brightly coloured sea slugs are often highly toxic, others are nontoxic and mimic the colouration of the toxic species. Their colours are mostly derived from pigments in their prey. There are also sea slugs that use their colouration to blend into their environments. -Sea slugs can obtain nematocysts by preying on sea

A stalked, sessile marine organism has several feathery feeding structures surrounding an opening through which food enters. The organism could potentially be a cnidarian, a lophophorate, a tube-dwelling worm, a crustacean, or an echinoderm. Which of the following traits, if found in this organism, would allow the greatest certainty of identification?

Use the following information to answer the questions below. Nudibranchs, a type of predatory sea slug, can have various protuberances (i.e., extensions) on their dorsal surfaces. Rhinophores are paired structures, located close to the head, which bear many chemoreceptors. Dorsal plummules, usually located posteriorly, perform respiratory gas exchange. Cerata usually cover much of the dorsal surface and contain nematocysts at their tips. -The crown-of-thorns sea star, Acanthaster planci, preys on the flesh of live coral. If coral animals are attacked by these sea stars, then what actually provides nutrition to the sea star, and which chemical (besides the toxin within their nematocysts)do the corals rely on for protection?

How is an arthropod's exoskeleton well adapted for life on land?

A terrestrial animal species is discovered with the following larval characteristics: exoskeleton, system of tubes for gas exchange, and modified segmentation. A knowledgeable zoologist should predict that the adults of this species would also feature

The clownfish readily swims among the tentacles of the sea anemones; the parrotfish avoids them. One hypothesis for the clownfish's apparent immunity is that they slowly build a tolerance to the sea anemone's toxin. A second hypothesis is that a chemical in the mucus that coats the clownfish prevents the nematocysts from being triggered. Which of the following graphs supports the second, but not the first, of these hypotheses?

The bivalves started to die one by one; only the undamaged shells remained. To keep the remaining bivalves alive, the teacher would have to remove the

If a lung were to be found in a mollusc, where would it be located?

Which of the following characteristics is common to all sponges?

A terrestrial mollusc without a shell belongs to which clade?

Use the following information to answer the questions below. An elementary school science teacher decided to liven up the classroom with a saltwater aquarium. Knowing that saltwater aquaria can be quite a hassle, the teacher proceeded stepwise. First, the teacher conditioned the water. Next, the teacher decided to stock the tank with various marine invertebrates, including a polychaete, a siliceous sponge, several bivalves, a shrimp, several sea anemones of different types, a colonial hydra, a few coral species, an ectoproct, a sea star, and several herbivorous gastropod varieties. Lastly, she added some vertebrates-a parrotfish and a clownfish. She arranged for daily feedings of copepods and feeder fish. -How many of the following organisms possess bilateral symmetry as adults? 1. sponges 2. molluscs 3. echinoderm 4. sea anemones 5. ectoprocts

Among the invertebrate phyla, phylum Arthropoda is unique in possessing members that have

Which of the following animal groups is entirely aquatic?

Which of the following is a characteristic of adult echinoderms?

Insects are a diverse and highly successful animal group. The internal anatomy of insects includes the following characteristics, with the exception of

What distinguishes complete metamorphosis from incomplete metamorphosis in insects?

Which of the following are entirely, or partly, composed of calcium carbonate?