Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Transcript of Mollusks
the Cambrian period. Today there are
over 80000 species of mollusks, including organisms such as snails, oysters, mussels, octopus and squids. All mollusks are invertebrates, meaning they have no backbones. Mollusks and Biological Diversity Mollusks are an active part of the food
web, with snails being prayed on by small
mammals and birds.They also help
decompose forest wastes, make soil
more rich in nutrients and keeps the water clean & healthy . As with all other
organisms, if mollusks were removed
from the food chain, it would collapse. They are also very sensitive to detect their environment's health , making them good biological indicators. Habitat Mollusks can be found in almost any habitat,
ranging from the ocean to a garden. They are an important part of almost every ecosystem in the world, from mountaintops to in between grains of sand to hot vents deep beneath the sea. Most mollusks are found in the oceans, many of them having protective shells to defend against predators in which they can hide. Some of the shells are very beautiful. Mollusks and Food! Mollusks are also used widely
around the world by humans for
food. Oysters, mussels, scallops and clams
are seafood staples to many. Escargot
is a French delicacy that is served all
over France. Even octopus is
sometimes used as food. This is Sannakji-a Korean
delicacy consisting of live
octopus tentacles that
still move on the plate! Yum! Clam Chowder in a
Bread Bowl Mollusks Structure Mollusks have soft bodies covered by a calcium-filled shell. They have 3 main parts, the headfoot, the visceral mass and mantle. Video! The headfoot has the sensory & motor organs, the visceral mass has the organs for digestion, excretion & reproduction, and the mantle is the specialized tissue which hides the shell. They also have a radula used for eating food materials like algae. Some use it for combat. Classes There are 6 classes of Mollusks: they are Amphineura, Monoplacophora, Gastropoda, Pelecypoda (Bivalvia), Scaphopoda, and Cephalopoda. Amphineura These kinds of Mollusks have worm-like bodies and no shell. Some of them do not have kidneys and are sometimes called "solenogasters" Monoplacophora They are flattened shell organisms. It only has one living genus left, which is Neopilina. Several of the families are extinct. Gastropoda This class is the largest group of Mollusks. They have snails, whelks, periwinkles, abalone and slugs and are seen both on salt/fresh water and on land. Most of them are herbivores which have multi-toothed radulas. Pelecypoda (Bivalvia) They have 2 shell pieces called valves. The organisms of this class are mussels, oysters, scallops and clams. Scaphopoda This class is a univalve cone-shaped organism. They are commonly called tusk shells or tooth shells and have no blood vessels and heart. Organisms of this class burrow themselves at the bottom of the oceans mud. Many are very tiny, about 6 cm (7 inches) long. Cephalopoda Endangered? Mollusks are endangered because of pollution occurring in water and land, many people around the world over-harvest them for food, killed for their unique shells and other mollusks like squids are often caught in fish nets where they quickly die. Most of these problems occur in the bivalve class. Solution! Nowadays, there are laws that can protect Mollusks. Many people are paying close attention to them making solutions like making oyster beds so we don't touch the organisms in the wild. Also people can stop destroying ecosystems of various descriptions, because it is likely that mollusks will form a large part of that ecosystem. In addition, we can farm mollusks that we eat rather than fishing them, which has no effect on ecosystems.
These actions taken will make them safe, untouched and unharmed for future generations to see. Phylum Mollusca How do mollusks fit into the Biological
classification system? Here is a chart for
a garden snail. Order Pulmonata Class Gastropoda Phylum Mollusca Kingdom Animalia Genus
Helix Species Helix Aspersa Family
Specific Mollusks and Biological Diversity (continued) Mollusks also represent a great amount of
biological diversity within their phylum. There
Are around 85 000 species of mollusks, living in
various habitats. In fact, scientists estimate that
there are more like 200 000 species of mollusks,
as many are undiscovered. We must therefore
protect and preserve all types of mollusks, as they form an important part in every ecosystem. Interesting Facts 500 species of mollusks live in the Philippines
Mollusks started evolution 500 million years ago.
Mollusks are wonderful biological indicators.
Female oysters can produce as much as 500 million eggs in a year.
Escargot, a land snail, is eaten by people around the world.
An octopus grows a new arm if it loses one of its eight arms.
Octopi have 3 hearts.
Most mollusks are capable of making pearls using foreign substances that enter their shell
Some mollusks are very rare and can only be found in very deep water
Most mollusks have shells
Many mollusks were extinct known as the fossils
Mollusks' shells are highly valued by collectors around the globe
Mollusks were extirpated from Utah, United States due to the overusage of water. Prehistoric Mollusks Mollusks have been around since the
Cambrian period-over 500 million years
ago. Mollusks from that period are called
trilobites, and are similar in appearance to
modern day beetles. Despite this, they were
still mollusks and lived in the ocean. Cartoon! This class includes squid, cuttlefish, octopus and nautilus. They are great swimmers and are carnivorous. Bibliography http://curiosity.discovery.com/question/mollusk-endangered
http://www.thewickednoodle.com/15-minute-england-clam-chowder/ picture: an oyster farm.