Unicellular plants: examples and characteristics

All organisms on Earth are divided into two large groups - cellular and noncellular. The latter include only viruses, and to the first - all other living beings. Cellular cells can be eukaryotes (they have a nucleus in the cell structure ) or prokaryotes (the nucleus is absent). The latter are represented by bacteria, and the first are all other groups of beings. The structure of most of them consists of many cells, but there are unicellular organisms, plants, mushrooms and even animals in this group. The latter include amoeba, infusoria, fungi - yeast, flour, penicillium.

Structure of cells of unicellular plants

These organisms belong to eukaryotes, that is, their DNA is in the nucleus, which performs a protective function. Like all plant cells, they contain specific organelles, such as vacuoles and plastids. Also in their structure are mitochondria, lysosomes, ribosomes, the Golgi complex and the endoplasmic reticulum, that is, a set of organelles standard for all eukaryotes.

Functions of organoids

Mitochondria perform one of the most important roles in the cell - they produce energy for all life processes. Lysosomes are responsible for intracellular digestion of nutrients. The functions of ribosomes are the synthesis of proteins from individual amino acids.

In the Golgi complex, some molecules are synthesized and all the cells produced by the cell are sorted.

The endoplasmic reticulum also participates in metabolism, accumulating minerals, synthesizing lipids and phospholipids. Organelles, which are inherent only in plant cells, also perform no less important functions. In chloroplasts there is a process of photosynthesis, and vacuoles serve as a reservoir for substances that are unnecessary to the cell.

Unicellular plants. Examples

Such organisms belong to the class of algae. The most striking example of a unicellular plant is chlamydomonas. This also includes chlorella and various types of diatoms.

Features of the structure

Unicellular plants of different species have their own distinctive features. Although they all consist of a single cell, they can have their own specific features.

Chlamydomonas is the most famous representative of unicellular algae. They differ from others in that they have organelles such as a photosensitive eye, through which organisms can determine where there is more solar energy for photosynthesis. Instead of numerous chloroplasts, they have one large, called chromatophore. Also in their structure are contractile vacuoles. They act as pumps, which pump out excess fluid. In addition, they have two flagella-organoids, which allow the body to move toward the light. One more single-celled plants are chlorella.

Like chlamydomonads, they belong to green algae, but do not have as many special organoids as the organisms described above. Their cells are typical plant.

Diatoms also belong to unicellular plants. They are the main component of plankton, which lives in large water bodies. They have a specific cell membrane that protects the body from the external environment. It consists of silicon dioxide, iron oxides , aluminum and other compounds. Of the remnants of these shells are formed many minerals. Most unicellular plants multiply by fission. All such organisms extract themselves nutrients in the process of photosynthesis, that is, autotrophs.