"Traian" High School, Constanta-Romania

1. Underwater Life
Meravi Aylin
Dumitrescu Laurentiu

2. Dolphins
 Dolphins are a widely distributed and
diverse group of fully aquatic marine
mammals. They are an informal
grouping within the
order Cetacea,excluding whales and por
poises, so to zoologists the grouping
is paraphyletic. The dolphins comprise
the extant families Delphinidae(the
oceanic dolphins), Platanistidae (the
Indian river dolphins), Iniidae(the new
world river dolphins),
and Pontoporiiade (the brackish dolphin
s). There are 40 extant species of
dolphins. Dolphins, alongside
other cetaceans, belong to the
clade Certadicyoda with even-toed
ungulates, and their closest living
relatives are the hippopotamuses, having
diverged about 40 million years ago.

3. Sharks
 Sharks are a group of fish characterized by
a cartilaginous skeleton, five to seven gill
slits on the sides of the head, and pectoral
fins that are not fused to the head. Modern
sharks are classified within
the cladeSelachimorpha (or Selachii) and
are the sister group to the rays. However, the
term "shark" has also been used for extinct
members of the subclass Elasmobranchii
outside the Selachimorpha, such
as Claudoselache and Xenachantus, as well as
other Condricthies such as
the holocephaild eugenedntidans. Under this
broader definition, the earliest known sharks
date back to more than 420 million years
ago. Acanthodians are often referred to as
"spiny sharks"; though they are not part of
Chondrichthyes proper, they are a paraphyletic
assemblage leading to cartilaginous fish as a
whole.

4. Corals
 Corals are marine
invertebrates in
the class Anthozoa of phyl
um Cnidaria. They
typically live in
compact colonies of many
identical individual polyps.
The group includes the
important reef builders
that inhabit
tropical oceans and
secrete calcium
carbonate to form a hard
skeleton.

5. Turtles
 Turtles are reptiles of
the order Testudines (or C
helonii) characterised by a
special bony or cartilagino
us shell developed from
their ribs and acting as
a shield."Turtle" may refer
to the order as a whole
(American English) or to
fresh-water and sea-
dwelling testudines
(British English).

7. Overall look:
 The Black Sea is a body of water between Southeastern
Europe and Western Asia, bounded
by Bulgaria, Georgia, Romania, Russia, Turkey,
and Ukraine. It is supplied by a number of major rivers,
such as the Danube, Dnieper, Rioni, Southern Bug,
and Dniester. The Black Sea has an area of
436,400 km2 (168,500 sq mi) (not including the Sea of
Azov), a maximum depth of 2,212 m (7,257 ft), and a
volume of 547,000 km3(131,000 cu mi). It is constrained by
the Pontic Mountains to the south and by the Caucasus
Mountains to the east, and features a wide shelf to the
northwest. The longest east-west extent is about 1,175 km
(730 mi).

8.  The Black Sea has a positive water balance; that is, a net outflow of
water 300 km3 (72 cu mi) per year through the Bosphorus and the
Dardanelles into the Aegean Sea. Mediterranean water flows into the
Black Sea as part of a two-way hydrological exchange. The Black Sea
outflow is cooler and less saline, and floats over the warm, more saline
Mediterranean inflow – as a result of differences in density caused by
differences in salinity – leading to a significant anoxic layer well below
the surface waters. The Black Sea drains into the Mediterranean
Sea and then the Atlantic Ocean, via the Aegean Sea and various straits.
The Bosphorus Strait connects it to the Sea of Marmara, and the Strait
of the Dardanelles connects that sea to the Aegean Sea region of the
Mediterranean. These waters separate Eastern Europe and Western
Asia. The Black Sea is also connected to the Sea of Azov by the Strait of
Kerch.
 More at: ://en.wikipedia.org/wiki/Black_Sea

10. • Eurasia
• North America
• Australia

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13. • Lion, Burcuta, Catfish, Coral
• Shark, Octopus, Dolphin, Clownfish
• Dolphin, Turtle, Shark, Coral

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16. • Yes!
• Of course!
• Yeah!

17. Thank you for taking the test! 