Baktéria

Baktéria are single-celled microorganisms that are found in virtually every environment on Earth. They are prokaryotes, meaning their cells lack a nucleus and other membrane-bound organelles. Bacteria vary greatly in size and shape, and they can be found in diverse forms such as spheres (cocci), rods (bacilli), and spirals (spirilla). Their genetic material is typically a single circular chromosome located in the cytoplasm.

Many bacteria play crucial roles in ecosystems. For instance, they are essential decomposers, breaking down dead organic matter and returning nutrients to the soil. In the digestive systems of animals, including humans, certain bacteria aid in the breakdown of food and the synthesis of vitamins. Photosynthetic bacteria, like cyanobacteria, contribute significantly to oxygen production in the atmosphere.

However, some bacteria are pathogenic, meaning they can cause disease in plants and animals. These disease-causing bacteria can infect various tissues and organs, leading to a range of illnesses. Fortunately, many bacterial infections can be treated with antibiotics, although the rise of antibiotic resistance is a growing concern. Bacteria reproduce asexually, primarily through binary fission, a process where one cell divides into two identical daughter cells. This rapid reproduction allows bacterial populations to grow quickly under favorable conditions.