Marine Invertebrates: Sponges and Cnidarians Unveiled

The video explores marine invertebrates, focusing on sponges and cnidarians. Sponges are ancient, porous creatures that filter feed and can reproduce in various ways. Cnidarians, including coral and jellyfish, are diverse and use different methods to capture food, such as venomous barbs. Both groups are among the earliest multicellular life forms on Earth.

What percentage of the world's animal life is made up of invertebrates?

• 97%

• 85%

• 75%

• 50%

Why do many invertebrates live in marine environments?

• Water provides support, reducing the need for a backbone.

• They cannot survive on land.

• They need sunlight to survive.

• They are attracted to the ocean's color.

What is a unique feature of sponges that allows them to filter water?

• Their ability to swim

• Their hard shell

• Their porous bodies

• Their tentacles

How can sponges reproduce?

• By laying eggs

• Only through mating

• By splitting into two

• Through regeneration and releasing larvae

What is a cnidarian?

• A type of fish

• A phylum of aquatic invertebrates including coral and jellyfish

• A type of sponge

• A marine mammal

How do jellyfish capture their prey?

• By using their teeth

• By swallowing them whole

• By trapping them in their tentacles

• By using spiny barbs with venom

What is unique about the digestive system of cnidarians?

• They do not digest food.

• They have a complete digestive tract.

• They have a digestive chamber instead of a tract.

• They digest food outside their body.

Which of the following is a difference between sponges and cnidarians?

• Sponges have a backbone.

• Cnidarians have a more complex structure.

• Sponges can move freely.

• Cnidarians are not aquatic.

What is the size range of cnidarians?

• Only a few centimeters

• From a few millimeters to the size of a football field

• The size of a small fish

• Up to a meter long

What is a common feature of both sponges and cnidarians?

• Both have a complete digestive tract.

• Both feed on microorganisms.

• Both are terrestrial.

• Both have a backbone.