Do echinoderms have coelom?

Echinoderms also have a spacious coelom (an open, fluid-filled body cavity lined with tissue), large gonads, and (usually) a complete gut.

Do gastropods have labial palps?

form and function in gastropods …the mouth form lobes called labial palps, which help to locate prey. The mouth itself frequently is prolonged into a proboscis that extends well in front of the tentacles.

Do jellyfish have central nervous systems?

Do they have brains? No, jellyfish have no single centralized brain. Instead, they have radially distributed nervous systems that are adapted to their unique body plan.

Do molluscs have a nervous system?

In the nervous system typical of mollusks, a pair of cerebral ganglia (masses of nerve cell bodies) innervate the head, mouth, and associated sense organs.

Do molluscs have an open or closed circulatory system?

Arthropods, such as this bee and most mollusks, have open circulatory systems. In contrast to a closed system, arthropods (including insects, crustaceans, and most mollusks) have an open circulatory system.

Do molluscs have central nervous system?

Snails and slugs have clusters of ganglia – bundles of nerve cells – which, in many species, are fused into a single organ; cephalopods have highly developed central nervous systems that enable them to navigate a maze, use tools, mimic other species, learn from each other and solve complex problems.

Do mollusks have a complete digestive system?

Clams (and all mollusks) have a complete digestive system. It consists of a mouth where food is ingested, a short connecting tube called the esophogus, a stomach which temporarily holds food, and an intestine where food digestion and absorption takes place.

Do mollusks have a respiratory system?

Basically all molluscs breathe by gills that are called ctenidia (comb-gills) because of their comb-like shape. In terrestrial molluscs this respiration organ is reduced, but still respiration takes place in the pallial cavity. That is why it is also called the snail’s respiratory cavity.

Do mollusks have tissues?

Mollusks have a hard outer shell. There is a layer of tissue called the mantle between the shell and the body. Most mollusks have tentacles for feeding and sensing, and many have a muscular foot. Mollusks also have a coelom, a complete digestive system, and specialized organs for excretion.

Do mollusks have ventral nerve cords?

Mollusks have ventral nerve cords. The tissue beneath the shell is called the mantle. The mantle cavity contains hemolymph.

Do nematodes have a nervous system?

In their overall structure, all nematode nervous systems exhibit a number of common, invariant features. The central nervous system consists primarily of a so-called circumoral brain or nerve ring, consisting of annular neuropil that encircles the neck of the pharyngeal muscle (Figure 1).

Do roundworms have a nervous system?

Roundworms also have a simple nervous system with a primitive brain. There are four nerves that run the length of the body and are connected from the top to the bottom of the body. At the anterior end of the animal (the head region), the nerves branch from a circular ring which serves as the brain.

Do sea sponges have nervous systems?

Sponges have no nervous system or organs like most animals do. This means they don’t have eyes, ears or the ability to physically feel anything. However, they do have specialized cells that carry out different functions within their bodies.

Do sponges have a nervous system?

Though sponges do not have traditional sensory or nervous systems, they were able to sense the stimuli applied by the scientists using only a cilium.

Do vertebrates have ventral tubular nervous system?

All vertebrates have a ventral tubular nervous system. … – All vertebrates have a notochord at some stage in their life cycle. – All vertebrates have a tail at some stage in their life cycle. – All vertebrates have pharyngeal gill slits at some stage in their life cycle.

Does coral have a nervous system?

Corals have no brain. A simple nervous system called a nerve net extends from the mouth to the tentacles. Chemoreceptor cells can detect sugars and amino acids which enable the coral to detect prey.

Does a jellyfish have a central nervous system?

Do they have brains? No, jellyfish have no single centralized brain. Instead, they have radially distributed nervous systems that are adapted to their unique body plan.

How do cnidarians catch prey and fight enemies?

All Cnidarians have tentacles with stinging cells in their tips which are used to capture and subdue prey. In fact, the phylum name “Cnidarian” literally means “stinging creature.” The stinging cells are called cnidocytes and contain a structure called a nematocyst.

How do cnidarians change generations?

Alternation of generations is a type of life cycle that switches between two forms, the asexual polyp and the sexual medusa. Each reproduction, one form will give rise to the other. For example, a polyp will go through asexual reproduction to produce medusae and vice versa with sexual reproduction among medusae.

How do cnidarians help the ecosystem?

They function to provide food and shelter to many organisms, including fish, invertebrates, and microorganisms such as algae. They also serve to protect the shoreline from erosion.

How do cnidarians poop?

Cnidarians take in food through their mouths, which is then digested in the coelenteron. Nutrients are then passed to other areas of the body for use, and waste products are expelled either through the mouth or through surface cells via water circulation.

How do echinoderms use their nerves?

Instead of a brain, echinoderms have a ring of nerves located around their mouth area that governs their nervous responses. This ring coordinates their motion, their eating, basically anything that requires nerve control.

How do the nervous system of clams and octopuses differ?

How do nervous systems of clams and octopuses differ? Octopuses have highly developed brains and well developed sense organs. Clams don’t have a brain and only simple sense organs.

How does echinoderm symmetry differ from that of cnidarians?

In what way does echinoderm symmetry differ from that of cnidarians? Cnidarians and echinoderms have radial symmetry; mollusks have bilateral symmetry. Cnidarians have no body cavity or cephalization; mollusks and echinoderms have a true coelom and cephalization.

How is the nervous tissue distributed in cnidarians?

The nerve net of each cnidarian species has a unique composition and the distribution of neurons throughout the body occurs by a density gradient along the proximal-distal axis. The density gradient goes from high to low from the proximal to the distal end of the Hydra.