Fun Trivia » Animals » Invertebrates » Echinoderms (Starfish, Sea Urchins, Etc.)

A sea cucumber is certainly not a protist. Protists are single-celled organisms with a nucleus, such as algae, some forms of aquatic slime, and protozoic organisms. In reality, they are animals, and they live as animals with the several functions that qualify animals, including the lack of cell walls and the lack of special substances which allow the sustained life of the organism. Difficulty: Average.

 

Plants, Neither, they are fungi, Neither, they are protists

Echinodermata is the correct answer to the question about the phylum of sea stars. This phylum includes not only sea stars, but also sea urchins, sand dollars, and sea cucumbers. Echinoderms are unique in that they have a water vascular system, which they use for movement, feeding, and respiration. They also have the ability to regenerate lost limbs, making them a fascinating group of animals to study. Some species of sea stars are even capable of reproducing asexually by splitting in half and regenerating into two separate individuals. Difficulty: Hard.

 

Arthropada, Porifera, Cordata

An interesting group including starfish, sand dollars, and sea cucumbers. Difficulty: Average.

 

smooth skin, grooved skin, no skin

Chordata are chordates, or organisms with spinal cords, or techically notochords. Hemichordata are acorn worms, marine invertebrates that technically have no notochord, but are stable and flexible. Nematoda are roundworms. Sea cucumbers instead follow the characteristics of echinoderms, including bilateral symmetry, tube feet, and external protective wall. Difficulty: Hard.

 

Chordata, Hemichordata, Nematoda

Sea stars, also known as starfish, have a unique skeletal system that sets them apart from other animals. Their skeleton is not made up of bones, but rather a network of small, interconnected plates called ossicles. These ossicles are made of calcium carbonate and are held together by a flexible tissue that allows sea stars to move and manipulate their arms. This flexibility also allows them to squeeze into tight spaces and pry open shells of their prey. Difficulty: Hard.

 

Exoskeleton, Green, Tough

A beach comber's treasure. Difficulty: Hard.

 

shell, bones, skeleton

Sea stars, also known as starfish, have a unique breathing system called the water vascular system. This system not only helps them breathe, but also aids in movement and feeding. The water vascular system consists of a series of canals and tube feet that are filled with seawater. The sea star can control the amount of water in its system, allowing it to inflate or deflate its tube feet for movement and feeding. This system also allows for gas exchange, as oxygen is absorbed through the tube feet and carbon dioxide is released back into the water. Difficulty: Hard.

 

Gills, Lungs, Air vital

Sea stars, also known as starfish, have the remarkable ability to regenerate most of their body parts. This means that if a sea star loses an arm or even its entire body, it can grow back the missing parts. In fact, some species of sea stars can even regenerate a whole new sea star from just a single arm! This incredible ability is due to the sea star's unique water vascular system, which allows it to transport nutrients and oxygen throughout its body and regrow lost tissue. Difficulty: Average.

 

reproduce asexually, reproduce sexually, find

Starfish can regenerate missing parts. An injury such as this may leave the animal susceptible to infection so regeneration can't be guaranteed. Difficulty: Average.

 

Turn into an oyster, Turn into a barnacle, Come back together

The life span will vary slightly from type to type of sea cucumber, as there are about 900 different kinds, but the general life span for the class of sea cucumbers is 5-10 years. Difficulty: Hard.

 

1-2 years, 4-7 months, 30-40 years

At the tip of each ray of a starfish is where you can find the eye spot. These eye spots are not like human eyes, but rather light-sensitive cells that can detect changes in light and dark. Starfish use these eye spots to navigate and find food, as well as to detect predators. Interestingly, some species of starfish have up to 50 eye spots on each ray! Difficulty: Hard.

 

Midpoint, Bottom, Inside

 

about 2000, about 3000, about 5000

The spines are attached to ball and socket joints, thereby giving them the ability to move in almost any direction. Difficulty: Hard.

 

Hinge joint, Pivot joint, Saddle joint

This is seen as projectile vomit, but it is not actually vomit at all. I don't know how much receiving this unpleasant reception would hurt, but it would certainly be disgusting. Difficulty: Hard.

 

Scurry away from the threat, Attempt to dig its way to safety, Explode, killing itself and the threat

Found only at sea and cannot be found in freshwater or land. Difficulty: Hard.

 

Fresh water, Land, All of the above

More specifically, it is most commonly eaten in China, Japan, and Taiwan. Difficulty: Average.

 

Northern Africa, Canada, The Middle East

 

Asteroidea, Echinoidea, Holothuroidea

It is a biological condition called "urchin barren sea". It commonly occurs when the otter population, which is highly responsible for keeping urchin populations down, is lacking. The problem is fairly easily restored by adding otters or other common predators of the urchin to the area. Difficulty: Hard.

 

Kelp, Otters, Mollusks

Urchins will pick up bits of things they find on the seafloor and carry them to hide from predators. Difficulty: Average.

 

Attract mates, Form shelter for the young sea urchins, Provide more surface area for the algae to form

Bilateral symmetry is where one half is a mirror image of the other. Radial symmetry on the other hand is when the object is divided into one or more sections which resemble each other. Think of it as a pie being divided into separate, yet equal portions. Difficulty: Hard.

 

six, ten, three