Inheritance Inheritance. Metachromatic leukodystrophy is inherited in an autosomal recessive manner. This means that both copies of the disease-causing gene in each cell must have a mutation for an individual to be affected. Individuals inherit two copies of each gene - one copy from each parent.
Crown-of-thorns starfish. Crown-of-thorns starfish are one of the most damaging creatures of tropical coral reefs, particularly Australia's Great Barrier Reef. They are voracious predators that release the contents of their stomach on to the coral.
Sea stars have a tough covering on their upper side, which is made up of plates of calcium carbonate with tiny spines on their surface. A sea star's spines are used for protection from predators, which include birds, fish and sea otters. One very spiny sea star is the crown-of-thorns starfish, which is shown here.