Animalscaretips
- What is the behavior of molluscs?
- What did molluscs evolve?
- What are the animals have two shells?
- Where did mollusks derive from?
- What makes Mollusca unique?
- What is unique about Mollusca?
- Why do Chitons have a poor fossil record?
- When did Mollusca first appear?
- What type of body cavity do mollusks have?
- How are seashells formed?
- What animal has the biggest shell?
- Which animal has the strongest shell?
- What is the difference between molluscs and mollusks?
- What characteristics distinguish mollusks from other organisms?
- What morphological feature gives Mollusca their name?
What is the behavior of molluscs?
The behavior of all molluscs, albeit to a lesser degree in cephalopods, involves simple reflexes that are mediated by Network A, schematized in Figure 2. Perhaps the best-known example is the defensive withdrawal response to a tactile stimulus.
What did molluscs evolve?
Fossil record
However, the evolutionary history both of the emergence of molluscs from the ancestral group Lophotrochozoa, and of their diversification into the well-known living and fossil forms, is still vigorously debated.
What are the animals have two shells?
Bivalves are mollusks with two shells such as clams and oysters. Univalves are animals with one shell such as a snail. Mollusks without shells include squid, banana slugs, and octopi. Some mollusks are terrestrial, occurring in most environments on earth, while others live in the water for some or all of their life.
Where did mollusks derive from?
The words mollusc and mollusk are both derived from the French mollusque, which originated from the Latin molluscus, from mollis, soft.
What makes Mollusca unique?
A feature unique to molluscs is a file-like rasping tool called a radula. This structure allows them to scrape algae and other food off rocks and even to drill through the shell of prey or catch fish. ... In creatures such as squid, the shell became small, moved inside the body and all but vanished.
What is unique about Mollusca?
Two unique features of mollusks are the mantle and radula (see Figure above). The mantle is a layer of tissue that lies between the shell and the body. It secretes calcium carbonate to form the shell. ... Predatory mollusks use the radula to drill holes in the shells of their prey.
Why do Chitons have a poor fossil record?
The fossil record of chitons is incomplete, sporadic, and geographically limited because the sampling record has been incomplete, sporadic, and geographically limited.
When did Mollusca first appear?
Mollusks have been diverse and abundant animals since earliest Cambrian time (about 545 million years ago = mya), and predate the appearance of trilobites in the fossil record.
What type of body cavity do mollusks have?
But molluscs have developed a true coelom, an internal body cavity enclosed by mesodermal membranes. The coelom in molluscs, however, is strangely reduced to a small space around the heart, sometimes called a hemocoel.
How are seashells formed?
“A seashell is a protective outer coating secreted by the animal's mantle, which is one of their muscles,” she said. The mantle forms the soft outer wall of their body. ... A mollusk produces calcium carbonate from its mantle, laying down layers of it over its lifetime. Together, those layers form the seashell.
What animal has the biggest shell?
The biggest are giant clams, Tridacna gigas. Their twinned shells can grow to well over a metre across and tip the scales at 200kg, the same as two newborn elephants. Giant clams, like all shell-making molluscs, sculpt their protective homes from calcium carbonate and gradually expand them throughout their lives.
Which animal has the strongest shell?
Sea snail shell the world's strongest material.
What is the difference between molluscs and mollusks?
mollusk, also spelled mollusc, any soft-bodied invertebrate of the phylum Mollusca, usually wholly or partly enclosed in a calcium carbonate shell secreted by a soft mantle covering the body.
What characteristics distinguish mollusks from other organisms?
Mollusks all have a mantle, a shell secreted by the mantle, a visceral hump, a foot, and a radula. Mollusks are different from other phyla because they have these things, most of which are unique to the phylum Mollusca.
What morphological feature gives Mollusca their name?
3. What morphological feature gives the phylum Mollusca its name? The word “mollusc” means “soft thing”. Molluscs have soft bodies and this feature explains the name of the phylum.
