Science 6

1. CORAL REEFS

2. - rocklike structure or
ecosystem that houses
different marine plants,
animals and other organism.
- Shelter of small brightly fish,
sea urchins, sea anemones,
and starfish.

3. Coral
- living polyp or coelenterate that
has a tubular and hollow body.
- Has a mouth surrounded with
tentacles
- Has a hard outer skeleton made of
calcium that stays together in a
fixed place to form the coral reef.
- Soft fine corals, sea fan corals, and
hard brain corals, grow together
with goldfish and other sea
dwellers.

4. Formation of Coral Reefs
- Coral and coral reefs are found in the warm, shallow waters around
the Philippine islands. Philippines is one of the world’s coral-rich
areas that provide shelter for a variety of marine life.
- Plenty – from the deep to the shallow waters in Northern Luzon,
West Palawan, the Visayas, and parts of Mindanao and Southern
Sulu Sea.
- Coral reefs are built by polyps or animals with soft bodies and
mouths that are surrounded by stinging tentacles. These animals
develop skeletons of limestone around themselves. They grow and
multiply by dividing into two and then they leave their skeletons
behind. These skeletons build up gradually to form the coral reef.

6. TYPES OF REEFS
All these types are found underwater, and differ in size, shape, and relation to a
nearby land.

7. - commonly formed near islands where
water is shallow. It is directly attached to
the shore.

8. - separated from the island shore by a
lagoon or a shallow stretch of water partly
separated from the sea by a strip of sand.

9. - circular reef with open water at the center.

10. ZONES IN CORAL REEFS
They vary according to the location and type oof reef. Some zones are not easily
recognized in other reefs.

11. - shallowest part of the reef.
- Tides (rising or falling of water)
always stir up the water in this
highest part of the reef.
- Sunlight could easily reach this
area enabling planktons to
undergo photosynthesis.
- Corals here feed on planktons.
- Red algae, small crabs, shrimps,
cowries, and other plants and
animals reside in the reef.
- shallow seafloor that surrounds
a reef.
- usually sandy floor where sea
grass meadows grow
- varied school of fish stay in this
zone

12. - also called reef floor, zone that
surrounds the oceanic islands
- Many fish shelter her because
there are plenty of planktons on
which they can feed
- Sponges, sea whip, sea fan, and
non-reef-building corals are
abundant
- zone above the reef floor
- where most marine animals live
because it provides an abundant
supply of invertebrates and algae
for food
- many cracks or crevices where
small fish hide for protection from
bigger animals looking for their
prey
- Massive corals and coralline algae
thrive here
- Many large fish like sharks,
barracudas, and tunas swim
through grooves in search for food.

13. - many corals and different kinds
of fish live here
- sandy bottom area that
surrounds a lagoon behind the
sheltered side of the main reef
- serves as protective area for
chunks of corals in the area
- supports a great number of
marine animals like mollusks,
worms, and crustaceans.
- quiet water area enclosed by
many coral reefs
- made up of bare rocks and
sand; thus, this area is less
affected by waves
- Small reef patches of algae and
invertebrates are present here

15. Life of Coral Reefs
- Coral reef are sometimes called
rainforests of the ocean because they
are home to most animals.
- It supports the relationships among
these animals.
- Ex: zooplanktons provide energy or
glucose to corals, corals in return
supply the zooplanktons the carbon
dioxide they need for [photosynthesis.

16. - Different kinds of fish inhabit coral reefs
- Small fish insert themselves in crack and
holes where they find shelter in the reefs.
- Marine animals in the reefs search for food
to survive, and some organisms provide
food for the other organisms
- Ex:
- Seaweeds are eaten by sea urchins
- Seabirds feed on sea urchins
- Decomposers thrive in coral reefs
(certain bacteria causes the dead
animals to decay)

17. - Crustaceans, fish, and mollusks feed on
algae
- Sea snakes feed only on fish and fish eggs
- Herons and pelicans feed on fish
- Monitor lizards, marine crocodiles and
semi-aquatic snakes swallow and feed on
small invertebrates
- Sea turtles eat sponges found in the coral
reefs

18. - Plant cells live on the tissue of coral polyp, these cells make food through
photosynthesis, and they supply food for the corals
- Corals reproduce sexually (during spawning season or the period when
corals release gametes or sex cells, corals release their egg cells and sperm
cells to be fertilized in the water. An external fertilization takes place
outside the polyp. When egg and sperm cells unite a tiny corals or polyps
formed) and asexually (budding).

20. INTERACTIONS OF CORAL REEFS
- Healthy corals mean clean and healthy water.
- Corals dies because of water pollution (oil spills and other pollutants thrown in
the water), pollutants hinder the growth of coral reefs, and the chemicals from
other toxic materials kill not only the fish but also the corals.
- During El Nino, the rising of temperature leads to drought which in turn brings
diseases and affect the growth and reproduction of coral reefs.

21. - Dinoflagellates stop making sugar for corals but instead produce harmful
substances. Corals spit the dinoflagellates out and stop producing the carbonate
shell. The color of the corals fades from yellow or brown to white. It is called coral
bleaching.
- Global warming also causes coral bleaching when corals are exposed to warm
surface water, which eventually destroys the coral reefs.

22. - Illegal methods of fishing: cyanide fishing, muro-ami fishing,and dynamite fishing
destroys coral reefs.
- Cyanide fishing – method in which fisher folk dive into the sea and spray
sodium cyanide (a poisonous compound). Result: destruction of coral reefs
- Muro-ami fishing – uses an encircling net and pounding device, which is
usually made of big stones fitted on a rope. This device is used to pound and
destroy the coral reefs to drive away the fish and other animals, which are then
caught using the net.
- Dynamite fishing – using explosive material, when it is thrown into the water,
the corals are destroyed and a large number of fish are killed, including the
small, recently hatched ones (also called fry)that are not yet mature enough for
consumption.

23. Importance of Coral Reefs
 Give economic benefit to people. They provide food through fisheries. They
provide fish and shellfish for many people living along the coastline.
 act as wave breakers that protect the shoreline. They absorb the energy from
the waves; thus, the force of big waves weakens as the wave bumps into the
reef. Coral reefs serve as barriers to tidal waves and break the big waves into
small ones.
 Corals are made into pieces of jewelry. They are also used for decorations at
home and in establishments. Crushed corals are sometimes used in building
roads and highways. They become part of sand and gravel used for
constructions.

24. Protection and Conservation of Coral Reefs
1. Conserve water
2. Help reduce pollution
3. Dispose of trash properly.
4. Plant trees
5. Volunteer for cleanup projects for coral reefs.