Sea Urchin

Why are sea urchins important for the ocean?

• They look pretty in the water.

• They help keep the underwater plants healthy.

• They make loud noises in the ocean.

• They build shelters for other sea creatures.

How do sea urchins protect coral reefs?

• By painting the coral reefs.

• By eating the plants that can harm the reefs.

• By singing to the coral reefs.

• By hiding from other sea creatures.

Sea urchins are called "unsung heroes" because:

• They are famous for their singing in the ocean.

• They are big and noticeable underwater.

• They do important work but don't get much attention.

• They wear capes and save other sea creatures.

What happens when there are fewer sea urchins in the ocean?

• Coral reefs become happier and healthier.

• The underwater world stays the same.

• The balance in the ocean gets mixed up.

• Algae growth decreases.

How do sea urchins protect themselves from danger?

• By turning invisible.

• By telling jokes to scare predators away.

• By hiding in small spaces.

• By using their sharp spines and toxins.

Why are sea urchins often unnoticed by people?

• They are very colorful and eye-catching.

• They are too busy building sandcastles.

• They are quiet and do their work quietly.

• They like to sing loudly in the ocean.

What do sea urchins eat to help the ocean?

• Other sea creatures.

• Coral reefs.

• Algae that can harm coral reefs.

• The sand at the bottom of the ocean.

What is the main role of algae in the ocean?

• Algae helps sea urchins hide from predators.

• Algae creates bubbles in the water.

• Algae is essential for other sea creatures to have oxygen and food.

• Algae is used as a playground for fish.

Sea urchins are compared to gardeners in the passage. Why?

• They carry gardening tools underwater.

• They grow underwater gardens.

• They help control the growth of underwater plants, like gardeners do on land.

• They teach other sea creatures how to garden.

What is the main idea of the passage?

• Sea urchins are noisy creatures in the ocean.

• Sea urchins are not important for underwater ecosystems.

• Sea urchins play a vital role in maintaining underwater balance by eating harmful algae.

• Algae does not affect the health of coral reefs in the ocean.