Ocean Habitats: Light and Dark Zones (video)
Science 8
1.
What is a habitat?
2.
What percentage of the Earth is covered by ocean? _________
3.
Ocean water contains minerals such as ________ and gases such as ___________,
nitrogen and carbon dioxide, which are necessary to the survival of ocean
organisms.
4.
Describe six ways light and dark zones of the ocean habitat are different.
5.
What are adaptations?
6.
Describe some adaptations of fish.
7.
Describe the light zone.
8.
Where are most living things found in the ocean?
9.
What is plankton?
10. How do large animals like whales survive on plankton?
11. Describe the dark zone.
12. If algae cannot grow in the dark, what food is available in the dark zone?
13. Describe some adaptations of living things found in the dark zone.
Ocean Habitats: Light and Dark Zones (video)
Science 8
1. A habitat is a place where plants and animals naturally live, which provides
food, water, and shelter.
2. The ocean is a salty, watery home to over 250,000 kinds of living things. It
covers approximately 70% of the Earth.
3. Ocean water contains minerals such as salt and gases such as oxygen,
nitrogen and carbon dioxide, which are necessary to the survival of ocean
organisms.
4. The light and dark zones of the ocean habitat are different in at least six
ways:
movement of the water amount of sunlight
temperature
pressure
availability of food
salinity of the water.
5. Adaptations are differences among living things that help them survive, to
get food and stay safe.
6. Fish have adapted in many ways to survive in their habitats. They have
different size and shape, consume(drink) a lot of water, breathe through gills,
have internal ears, secrete mucous, and some are camouflaged.
7. The light zone the sunlight reaches down about 100-200 meters below the
water. The light zone is divided into two parts, the continental shelf and the
open ocean.
8. Most of the ocean life is on the continental shelf. Rivers and currents provide
nutrients to kelp forests and sea grass meadows on the continental shelf. The
open ocean contains less food than the shelf waters so there are fewer living
things.
9. Tiny algae and small animals that eat algae are called plankton.
10. Blue whales have a special adaptation in their mouths called baleen, which
allows them to eat plankton.
11. The dark zone is a harsh environment, having no sunlight, little food, cold
water, and extreme water pressure.
12. The mid-water layer of the dark zone is located where the continental shelf
ends and the land of the continental slope plummets down. There is very little
light in this layer. Many of the animals here feed off of the dead organic
material that washes down the continental slope from the light zone.
13. Dark zone creatures have made special adaptations in order to live in their
harsh environment. Some fish, like the lantern fish and the flashlight fish,
make their own light through chemical reactions. Many fish migrate up to the
light zone at night in order to hunt and feed.