Question 2 of 21

What is the common factor uniting spiders, wood lice and crabs?

... They all belong to the same phylum or major division of the animal world.

Question 3 of 21

How many species of crustaceans are there?

... It is estimated that there are some 25,000 species.

Question 4 of 21

How many segments can there be in a crustacean's body?

... The body can be made up of up to 50 segments.

Question 5 of 21

What is the cephalothorax?

... It is a unit comprised of the head and the thorax.

Question 6 of 21

What is the chitin?

... It is a hard substance covering the body and forming an external skeleton.

Question 7 of 21

As the crustacean grows, how does the chitin develop?

... The chitin does not grow -- it is shed and a new one grows.

Question 8 of 21

How does the crustacean find its way?

... It has compound eyes with many lenses.

Question 9 of 21

If the crustacean uses its claws for grasping and eating, how does it walk?

... The claws are used for grasping, eating and walking.

Question 10 of 21

How many segments does the body of the lobster have?

... It belongs to the high society of crustaceans that have only 19 segments, unlike the lower class with up to 50 segments.

Question 11 of 21

What are Entomostraca?

... They are smaller crustaceans without distinct body regions.

Question 12 of 21

What is the ecological effect of larger, water dwelling crustaceans?

... They are scavengers. They help keep the streams and beaches clean.

Question 13 of 21

How do land-dwelling crustaceans contribute to agriculture?

... Most of these crustaceans are pests and as such their impact on agriculture is negative.

Question 14 of 21

What do lobsters, sandhoppers and wood lice have something in common?

... They all belong to the high society of crustaceans with 19 body segments.

Question 15 of 21

In what part of the world are barnacles a delicacy?

... In parts of Europe and South America the barnacle is a delicacy.

Question 16 of 21

For what type of cuisine is the crayfish the main ingredient?

... Crayfish are the main ingredient in spicy Creole and Cajun cuisines of Louisiana.

Question 17 of 21

Which marine creature enjoys a meal of krill?

... Many whales find the krill to be a main source of nutrients.

Question 18 of 21

What are the smallest crustaceans?

... The water flea can be as small as 1/125 inch (0.2 millimeter) long.

Question 19 of 21

Of all the crustaceans, which are the most common?

... The most common are copepods, tiny organisms that swim or float.

Question 20 of 21

Are crustaceans in any danger?

... Because most are small, numerous and widely distributed, there is no concern for their survival.

Question 21 of 21

What is the average size of lobsters caught today?

... The average size is about 1 pound (0.45 kilogram) as opposed to 20 to 40 pounds (9 to 18 kilogram) in the past