3.4 The Open-ocean and Deep-sea Ecosystems

Question 1

_________ are a commonly encountered group of plankton. They are also known as arrow-worms because of their arrow-shaped body. They are transparent, which helps in camouflage. They have large jaws with bristles, which they use to capture their prey.

Kee–t…

Answer 1

Chaetognaths

Question 2

_______ are crustaceans. Most species are planktonic. Copepods are the most numerous form of plankton in the oceans. They are an important source of prey for fish larvae and are essential for maintenance of good fish stock.

Ko–

Answer 2

Copepods.

Question 3

_____ are also planktonic crustaceans. They have pincer-like feeding appendages and large, well-developed eyes, which they use to locate and capture their prey. Some deep-water amphipods are scavengers.

Answer 3

Amphipods

Question 4

______ or ____ are another abundant group of zooplankton. They are also crustaceans. They are found in abundance in polar regions. They feed on phytoplankton and other small zooplankton. They are an important source of food for nekton species such as fish and whales.

You–f

Answer 4

Euphausids, krill.

You–fah–zeeds

Question 5

________ are also plankton. Their size varies from a few millimeters to a few meters in length. They have soft, translucent bodies. They belong to a group called cnidarians. They have specialized stinging cells they use to capture prey.

Answer 5

Jellyfish.

Question 6

Photic

Answer 6

Light

Question 7

Aphotic

Answer 7

Lightless

Question 8

the production and emission of light by a living organism.

Answer 8

Bioluminescence