Aquatic and Marine Biology

Acrodont teeth are found in fishes and amphibians.

Humans are heterodont and diphyodont.

In Carcharias taurus (sand tiger shark), young ones eat each other within the womb until only two are left in each uterus. This is done to limit competition for resources.

Retractable and prehensile penis is a characteristic of dolphins. A male dolphin can use its penis to explore objects, just like a hand.

In Percula clownfish, male turns into female if the breeding female dies. This guarantees that breeding female is always available.

Correct. The outer skeleton of the snail is the shell, which  is made up of calcium carbonate. The snail pulls this shell along as it moves. The snail can even hide its head inside the shell.

2 classes have both marine and freshwater habitats. Only bivalves and gastropods are found in both freshwater and seawater.

Bivalves are excellent water quality biosentinels. Therefore, they were exploited in Mussel Watch Program to measure the level of contamination of water.

Pinctada margaritifera and Pinctada martensii (marine oysters) are known for their best natural pearls. They live in the tropical and subtropical waters of the Pacific Ocean.

Sea silk is produced by a large marine bivalve mollusk, Pinna nobilis.

Balanoglossus represents a connecting link between non-chordates and chordates.

The hard shell of sea animals is made of a chemical compound called calcium carbonate that protects them from mechanical injury.

In hydra, water enters and is expelled through the mouth as there is no anus

In starfish, locomotion is done by tube feet.

Flyingfish or exocoetus is a fish.