All organisms on Earth are divided into two large groups - cellular and non-cellular. The latter include only viruses, and the former - all other living things. Cellular can be eukaryotes (they have a nucleus in the structure of cells) or prokaryotes (there is no nucleus). The latter are represented by bacteria, and the remaining include all other groups of creatures. The structure of most of them consists of many cells, but in this group there are unicellular organisms, plants, fungi, and even animals. The latter include amoeba, ciliates, and fungi include yeast, mucor, and penicillus.
Cell structure of unicellular plants
These organisms belong to eukaryotes, that is, their DNA is located in the nucleus, which performs a protective function. Like all plant cells, they contain specific organelles, such as vacuoles and plastids. Also, their structure includes mitochondria, lysosomes, ribosomes, the Golgi complex and the endoplasmic reticulum, that is, a set of organelles, standard for all eukaryotes.
Organoid Functions
Mitochondria perform one of the most important roles in the cell - they generate energy for all vital 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 substances produced by the cell are sorted.
The endoplasmic reticulum is also involved in metabolism, accumulating minerals, synthesizing lipids and phospholipids. Organelles, which are inherent only to plant cells, also perform no less important functions. The process of photosynthesis takes place in chloroplasts, and vacuoles act as a reservoir for substances unnecessary to the cell.
Unicellular plants. Examples
Organisms of this kind 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.
Structural features
Unicellular plants of different species have their own distinctive features. Although they all consist of one 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, with which organisms can determine where more solar energy is located for photosynthesis. Instead of numerous chloroplasts, they have one large, which is called a chromatophore. Also their structure includes contractile vacuoles. They act as pumps that pump out excess fluid. In addition, they have two flagella-organoids, which allow the body to move in the direction of the light. Another unicellular plant is chlorella.
Like chlamydomonas, they belong to green algae, but do not have as many special organoids as the organisms described above. Their cells are typical plant cells.
Diatoms also belong to unicellular plants. They are the main component of plankton that lives in large bodies of water. They have a specific cell membrane that protects the body from the environment. It consists of silicon dioxide, iron oxides , aluminum and other compounds. Many minerals are formed from the remains of these shells. Most unicellular plants reproduce by division. All such organisms obtain nutrients in the process of photosynthesis, that is, they are autotrophs.