Are shells living things? What are the shells in the river called?

In recent years, with the improvement of people's living standards, traveling has become a new fashion for people, which can also broaden people's horizons and get in touch with nature. If you travel to the seaside, you will definitely see all kinds of beautiful shells. Simple shells are the mantles of molluscs living by the water. They are a kind of calcification formed by the secretion of a special glandular cell of molluscs to protect the soft part of the body. Let's learn more about it!

Contents of this article

1. Are shells living things?

2. What are the shells in the river called?

3. Do all mollusks have shells?

Are shells living things?

If it is a simple shell, it is not a living thing. If there is a mollusk inside, it is a living thing. Simple shells are the mantle of mollusks living near the water. They are a kind of calcification, the main component of which is calcium carbonate, and do not have the basic characteristics of living things.

Simple shells are calcified structures formed by secretions from a special glandular cell of a mollusk to protect the soft part of the body.

The main components of shells are calcium carbonate and organic matter, of which the content of calcium carbonate is as high as about 95%.

The essential difference between living things and non-living things lies in whether they are alive. Living things have the following characteristics: they have cell structure, can carry out metabolism, can grow, are sensitive to stress, etc.

What are the shells in the river called?

The shells in the river are called river clams, which are a kind of mollusk, and in some places they are also called mussel shells. They live at the bottom of freshwater lakes, ponds, rivers, etc., half buried in mud and sand. Their meat can be eaten, and can also be used as bait and feed for fish and poultry. In some areas, there are also freshwater pearl oysters that can produce pearls.

River clams generally live in muddy, sandy or gravelly areas of rivers, lakes, ponds and streams. They like to half bury their bodies in the mud and sand, with only the rear half exposed for breathing and feeding.

Because river clams have weak mobility and cannot chase food, they usually open and close their shells to allow food to flow into the clam body with the water, and they also move forward by opening and closing their shells.

River clams usually reproduce in the summer. Their fertilized eggs usually develop in the gill cavity, and their larvae will develop into hookworm larvae after hatching.

Do all mollusks have shells?

Molluscs do not necessarily have shells. Having a shell outside the body is an important feature of molluscs. The study of molluscs is also called conchology. Most molluscs have one, two or more shells in different shapes. Some species have shells that degenerate into inner shells, and some have no shells.

Molluscs, also known as shellfish, are a general term for animals in the phylum Mollusca, the largest group except arthropods.

The basic characteristics of mollusks are very similar. Their bodies are soft and most of them are not segmented. They are generally divided into four parts: head, foot, viscera and mantle.

Molluscs vary greatly in morphology, but all have soft bodies and most live in the ocean, with only some bivalves and gastropods migrating to brackish and fresh water.