Bumblebees of the subgenus Psithyrus (known as 'cuckoo bumblebees', and formerly considered a separate genus) are brood parasites, sometimes called kleptoparasites, in the colonies of other bumblebees, and have lost the ability to collect pollen.ueen and worker bumblebees can sting. Unlike in honeybees, a bumblebee's stinger lacks barbs, so the bee can sting repeatedly without injuring itself; by the same token, the stinger is not left in the wound. Bumblebee species are not normally aggressive, but may sting in defence of their nest, or if harmed.
STEM CELLS SAVE LIVES. For decades, doctors have harnessed the unique ability of stem cells to treat leukemia and genetic blood diseases. But now, researchers are discovering that these cells have the power to heal, to fight disease, and to regenerate damaged or aging tissue throughout the body. To fully understand why they hold the potential to change your childâs medical future, get to know more about stem cells.
Skin stem cells. In everyday life your skin has to cope with a lot of wear and tear. For example, it is exposed to chemicals like soap and to physical stresses such as friction with your clothes or exposure to sunlight.The epidermis and skin appendages need to be renewed constantly to keep your skin in good condition. These stem cells are found in the basal layer of the epidermis. 2  Hair follicle stem cells ensure constant renewal of the hair follicles. 3  They can also regenerate the epidermis and sebaceous glands if these tissues are damaged. 4  Hair follicle stem cells are found throughout the hair follicles.