GENERAL HISTOLOGY

Detailed explanation-1: -There are close to 2, 000 species of sea stars in the world’s oceans. Most species have five arms, but some have many more-even as many as 40! At the Aquarium, you can see 10 species of sea stars throughout the exhibits. Look closely in the kelp forest habitat to spot the sun sea stars, which have 20 arms each!

Detailed explanation-2: -Most sea star species have five arms but many have more. The sunflower sea star can have up to 24 arms. Longevity: Sea stars can live a relatively long time. Some species, including the sunflower sea star, Pycnopodia helianthoides, live for more than 30 years.

Detailed explanation-3: -Rays: Common sea stars have five rays, unless they lose one or grow an extra. Most sea stars have 5-14 rays, but sunflower sea stars can have up to 15-24 rays. If a sea star loses a ray to a predator or an accident, it can grow a new one back again. The process of growing a new ray is called regeneration.

Detailed explanation-4: -This starfish that forms a cross in a circle belongs to a species that is widespread in the Indo-Pacific Ocean: the comb sea star (Astropecten Polyacanthus). But this specimen, which comes from Bohol in the Philippines, is not common, since it has only 4 arms.