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.
This is why red blood cells appear red. Heamoglobon is the pigment which binds oxygen for transport throughout the body. When oxygen is bound the RBC appears light red in color. When oxygen is not bound it (and is replaced by carbon dioxide) it appears a darker shade of red, almost a burgundy color.