Some of the information were taken from the net. Presentation was made to help my cookery students.

2.  is any form of marine life regarded
as food by humans.
 the term seafood applies also to
any fresh water life eaten by
humans
 The harvesting of wild seafood is
known as fishing and the cultivation
and farming of seafood is known
as aquaculture or mariculture

3.  is part of a large group of invertebrate animals
comprising approximately 93,000 recognized
living marine species. These include animals
such as snails, squids, octopi, clams, mussels,
scallops and oysters that constitute popular yet
extravagant foods. Molluscs are especially
popular in France, New England, Japan and
China.
Molluscs have a somewhat rubbery taste and
are often cooked in butter and seasonings.
They are primarily eaten for lunch and dinner.
Molluscs can be eaten for breakfast but aren't
considered traditional breakfast foods.

4.  Mollusks are commonly fried, grilled,
breaded, sautéed or mixed with
vegetables or made into a salad. Potential
meal ideas can include fried or grilled
calamari, breaded calamari rings, oyster
casinos, Thai mussels with squash, fried
clams with blue cheese dip, bay scallop
rolls, mussels mariniere, and a seafood
stew with sausage, tomatoes, herbs and
wine.

5.  certain oysters, clams and mussels are tagged
with labels indicating that they were harvested
and processed in accordance with the national
shellfish safety controls. Choosing the right
molluscs is important for proper health. Because
molluscan shellfish eat by filtering food from the
surrounding water, they may accumulate
bacteria, viruses and chemicals at a much higher
concentration than the rest of the environment.
You are therefore advised to throw away any
shellfish if their shells are cracked or broken.
Not all post-harvest treatments designed to
eliminate contaminants are equally effective, so
raw oysters should be avoided, especially by
people at risk for particular food-borne illnesses.

6. include the crabs, lobsters, crayfish,shrimp,
krill, barnacles brine shrimp, copepods,ostracods
and mantis shrimp. Crustaceans are found in a wide
range of habitats - most are free living freshwater or
marine animals
many crustaceans, especially the larger decapods (crabs,
lobsters, shrimp, and prawns) are eaten by humans and
are therefore important to human economies. Krill are
also caught in large amounts.
Small planktonic crustaceans, such as copepods, water
fleas, and krill, are major links between the
photosynthetic phytoplankton and larger carnivores such
as fish and whales in marine food webs. Other crustaceans
are crucial in recycling nutrients trapped in the bodies of
dead organisms.

7.  spiny-skinned invertebrates that live on the ocean floor.
The word echinoderm means "spiny skin." No echinoderms
are found in fresh water. Modern-day echinoderms have
five-fold symmetry (they are pentameral), having arms or
rays in multiples of five.
 Sea cucumbers are also considered a delicacy in some
countries of south east Asia; particularly popular are
the pineapple rollerThelenota ananas (susuhan) and the
red Halodeima edulis. They are well known as bêche de
mer or Trepang in China and Indonesia. The sea cucumbers
are dried, and the potentially poisonous entrails removed.
The strong poisons of the sea cucumbers are often
psychoactive, but their effects are not well studied. It
does appear that some sea cucumber toxins restrain the
growth rate of tumour cells, which has sparked interest
from cancer researchers.avoid those with sunken eyes.
The skin should be shiny, moist and firm and the scales
firmly attached. There should be a faint sea fresh aroma.

8.  Seaweeds are also harvested or cultivated for
the extraction of alginate, agar and carrageenan,
gelatinous substances collectively known
as hydrocolloids or phycocolloids. Hydrocolloids
have attained commercial significance as food
additives.The food industry exploits their gelling,
water-retention, emulsifying and other physical
properties. Agar is used in foods such as
confectionery, meat and poultry products,
desserts and beverages and moulded foods.
Carrageenan is used in salad dressings and
sauces, dietetic foods, and as a preservative in
meat and fish products, dairy items and baked
goods.

9. In Asia, Nori (in Japan), Zicai (in China), and Gim(in
Korea) are sheets of dried Porphyra used in soups or
to wrap sushi. Chondrus crispus (commonly known
as Irish moss orcarrageenan moss) is another red
alga used in producing various food additives, along
with Kappaphycus and various gigartinoid
seaweeds. Porphyra is a red alga used in Wales to
make laver. Laverbread, made from oats and
the laver, is a popular dish there. Affectionately
called "Dulce" in northern Belize, seaweeds are
mixed with milk, nutmeg, cinnamon, and vanilla to
make a common beverage.

10. In Asia, Nori (in Japan), Zicai (in China), and Gim(in
Korea) are sheets of dried Porphyra used in soups or
to wrap sushi. Chondrus crispus (commonly known
as Irish moss orcarrageenan moss) is another red
alga used in producing various food additives, along
with Kappaphycus and various gigartinoid
seaweeds. Porphyra is a red alga used in Wales to
make laver. Laverbread, made from oats and
the laver, is a popular dish there. Affectionately
called "Dulce" in northern Belize, seaweeds are
mixed with milk, nutmeg, cinnamon, and vanilla to
make a common beverage.