Despite the fact that biologists managed to isolate the global kingdoms of plants and animals many centuries ago, it is still quite difficult to draw a clear line between them. Nevertheless, the first attempts to derive the basic qualities of a plant and animal organism were made by Karl Linnaeus. Today, the experience accumulated by researchers around the world has allowed us to formulate the main theses that explain how animals differ from plants.
Cytological level
How do animals differ from plants in the first place? Speaking about the structure of plant and animal cells, it is worth noting that they have a similar structure and function. Each living cell contains a nucleus that carries hereditary information, as well as coordinating the processes of cell support; a membrane that limits the cell space and performs protective functions; cytoplasm, filling the space between them and responsible for the transport of necessary substances. However, there are significant differences between the cells of plants and animals. The plant cell cytoplasm contains plastids, which include chlorophyll, a substance that stains the green parts of plants and is involved in photosynthesis. The plant cell is also characterized by the presence of a rigid cell wall, allowing it to maintain its shape and demonstrate resistance to deformation. In turn, the animal cell has centrioles located in the cytoplasm and playing an important role in the process of mitosis.
The activity of living organisms
Another difference between animals and plants is the activity shown by organisms. The activity of animal organisms in search of food, adaptation to the environment remains invariably high throughout their lives, only slightly decreasing and reaching a peak in certain periods. Plant activity is much lower. The motor activity of the plant includes only forced tropisms, carried out under the influence of external factors (sunlight, earth's attraction, etc.).
Methods of feeding organisms
A significant difference between plants and animals also affects their way of feeding. Being autotrophic organisms, plants are able to independently produce organic matter from inorganic. Animals are heterotrophic organisms, the distinguishing feature of which is the ability to absorb finished organic matter and the inability to become a producer of organic matter from inorganic.
Types of growth of organisms
Considering how animals differ from plants, one cannot but touch upon the problem of the growth of organisms. Plant growth is continuous and relatively uniform throughout the entire period of its life. The growth of the animal organism is carried out exclusively within certain periods and this happens extremely unevenly, reaching a peak value and almost dying out at one time or another. Nevertheless, even having examined how animals differ from plants, we cannot draw a clear line between these categories.
