Some insects, amphibians, mollusks, crustaceans, echinoderms, and tunicates undergo metamorphosis. In metamorphosis, the immature form can look very different from the adult form (complete metamorphosis) or it can resemble the adult form (incomplete metamorphosis).
Do crustaceans have pedipalps?
Pedipalps are traditionally thought to be homologous with mandibles in crustaceans and insects, although more recent studies (e.g. using Hox genes) suggest they are probably homologous with the crustacean second antennae.
Do crustaceans have a circulatory system?
Crustaceans have an open circulatory system meaning that all their blood is not contained within vessels, instead, blood is drawn in to the heart through holes called ostia, then pumped out again to circulate through the tissues and return again to the heart.
Do crustaceans produce eggs?
Normal sexual reproduction involves the fusion of a sperm with an egg, but some crustaceans are parthenogenetic; that is, they produce eggs that develop without being fertilized by a sperm. Many branchiopods can do this, as can some ostracods and some isopods.
Do echinoderms molt?
Echinoderms have an exoskeleton. Echinoderms molt.
Do gastropods have a complete digestive system?
The highly modified parasitic genus Enteroxenos has no digestive tract at all, and simply absorbs the blood of its host through the body wall. The digestive system usually has the following parts: buccal mass (including the mouth, pharynx, and retractor muscles of the pharynx) and salivary glands with salivary ducts.
Do gastropods have bilateral symmetry?
Externally, gastropods appear to be bilaterally symmetrical. However, they are one of the most successful clades of asymmetric organisms known.
How are detritivores different from decomposers provide an example of each?
Detritivores are different from other decomposers in that they consume material to break it down. Decomposers like bacteria and fungi don’t eat their food, they decompose it externally. … Some examples of detritivores are worms, millipedes, dung flies, woodlice, slugs, sea stars, crabs and sea cucumbers.
How do carnivorous gastropods feed?
For feeding, gastropods use a radula, a hard plate that has teeth. Gastropod feeding habits are extremely varied, although most species make use of a radula in some aspect of their feeding behavior. Some graze, some browse, some feed on plankton, some are scavengers or detritivores, some are active carnivores.
How do crustaceans avoid predators?
Marine crustaceans have a very wide range of predators from mammals like sea otters and seals, other crustaceans, molluscs (e.g. octopuses), sea birds, fish and humans. They protect themselves by a variety of methods – their hard exoskeletons, their chelipeds, camouflage and rapid escape (burrowing or swimming away).
How do crustaceans excrete wastes?
Most crustaceans excrete the end product of nitrogen metabolism, in the form of ammonia, through the gills. Some of the more terrestrial forms produce urea or uric acid, which are far less toxic than ammonia.
How do gastropods function as decomposers?
Most gastropods, however, are useful to humans in that they help decompose dead plants and animals into substances that can be used by plants to manufacture new organic compounds.
How do mollusks filter feed?
Mussels are filter feeders, which means they are like a small living pump. They draw in water from one side and they pump it out the other side, but in between they’ve got a massive rack of filters. And those filters work as gills, so they’re extracting oxygen out of the water but they’re also extracting food.
How do the appendages of crustaceans differ from other subphyla?
Crustaceans are generally aquatic and differ from other arthropods in having two pairs of appendages (antennules and antennae) in front of the mouth and paired appendages near the mouth that function as jaws.
How does the antennae of crustaceans differ from the antenna of other arthropods?
Insects display a wide variety of antennal shapes. Antennae (singular antenna) are paired appendages connected to the anterior-most segments of arthropods. In crustaceans, they are present on the first two segments of the head, with the smaller pair known as antennules and the larger pair biramous (branched).
How many body sections do crustaceans have?
Crustaceans have segmented bodies like insects! Their bodies are divided into three sections – the head, the thorax, and the abdomen. The head has two pair of antennae, a pair of compound eyes, and a pair of mandibles.
Is mollusca a decomposer?
Both shelled snails and slugs can generally be categorized as decomposers, though they play only a small role compared to other decomposition organisms.
Is seagrass a producer consumer or decomposer?
Tiny producers such as algae, bacteria, and seagrass absorb minute amounts of these pollutants. Primary consumers, such as sea turtles and fish, eat the seagrass. They use the energy and nutrients provided by the plants, but store the chemicals in their fatty tissue.
Is a bivalve a herbivore?
Suspension-feeding bivalve molluscs consume at the lowest trophic level, feeding largely as herbivores (Duarte et al., 2009).
Is a crab a carnivore herbivore or omnivore?
Are crabs carnivores, herbivores, or omnivores? Almost all crabs are omnivores. They eat algae and other plant matter as well as hunting animal prey.
Is a dog a decomposer?
Dogs, bears, and raccoons are also omnivores. Examples of consumers are caterpillars (herbivores) and hawks (carnivore). Decomposers ( Figure 1.2) get nutrients and energy by breaking down dead organisms and animal wastes.
Is a mollusk a decomposer?
Other sea creatures classified as decomposers include crustaceans and mollusks, bacteria, fungi, sea cucumbers, starfish, sea urchins, and other kinds of marine worms.
Is an echinoderm a crustacean?
shellfish, any aquatic invertebrate animal having a shell and belonging to the phylum Mollusca, the class Crustacea (phylum Arthropoda), or the phylum Echinodermata.
Is crustacean a class or order?
Classification of insects and mites The Crustacea are a large class divided into 8 subclasses and about 30 orders. Most species of Crustacea are aquatic and are found especially in salt water. Many crustaceans, including crayfish, lobsters, and prawns, serve as important human food.
Is seagrass a decomposer?
Their leaves and stems also provide food for herbivores like sea turtles and manatees. Plankton, algae, and bacteria grow on seagrass stems, providing food for additional organisms. Dead seagrasses provide food for decomposers like worms, sea cucumbers, crabs, and filter feeders.
Is seagrass a herbivore?
Herbivores in tropical seagrass meadows are diverse, with a range of feeding strategies, each influencing meadows differently.
What adaptations do crustaceans have?
A marine crab’s adaptations include: their hard exoskeleton, their claws, and their concealing coloration—when an animal hides itself against a background of the same color.
What are decomposers and detritivores?
While decomposers break down dead, organic materials, detritivores—like millipedes, earthworms, and termites—eat dead organisms and wastes.