euglenozoans

Euglenozoans are a diverse group of flagellated eukaryotes. They are characterized by the presence of two flagella, one typically anterior and the other posterior. Many euglenozoans possess a pellicle, a flexible proteinaceous layer beneath the plasma membrane that provides structural support. A prominent feature is the presence of a cytostome, or cell mouth, and a cytopharynx, through which food particles are ingested. Some euglenozoans are photosynthetic, containing chloroplasts, while others are heterotrophic, absorbing nutrients from their environment or phagocytosing food.

The group is divided into several major classes, including Euglenida and Kinetoplastida. Euglenids are primarily freshwater organisms, many of which are photosynthetic. They are known for their ability to move using flagella and also through body contortions, a process called metaboly. Kinetoplastids, on the other hand, are often parasitic, causing significant diseases in humans and animals. They are distinguished by the presence of a kinetoplast, a large mitochondrion containing extranuclear DNA. Examples of kinetoplastids include Trypanosoma, the causative agent of sleeping sickness, and Leishmania, responsible for leishmaniasis. Euglenozoans inhabit a wide range of environments, from marine and freshwater to soil and the bodies of other organisms.