But the arrival of the dockless bike-share model was received mostly with praise and excitement in a city that has embraced biking as a mode of transportation. Some biking aficionados said they hope the companies will indeed bring more bikes to underserved communities of the District, including the Northeast and Southeast quadrants.
It sounds super-gross but please try to imagine it: Red muscles, pink muscles, and white muscles. The red muscles are red because they contain lots of myoglobin: a protein that binds iron and oxygen. Your blood has a similar protein called hemoglobin which binds iron and oxygen.
Muscle tissues are derived from the mesodermal layer of embryonic germ cells in a process known as myogenesis. There are three types of muscle, skeletal or striated, cardiac, and smooth. Type I, slow twitch, or red muscle, is dense with capillaries and is rich in mitochondria and myoglobin, giving the muscle tissue its characteristic red color. 2  It can carry more oxygen and sustain aerobic activity using fats or carbohydrates as fuel.