All of the blood cells in your body are mixed together in a slightly yellowish liquid called Plasma. Plasma is mostly made up of water, but also contains proteins, sugar and salt. In addition to carrying blood cells throughout your body, plasma also carries hormones, nutrients and chemicals, such as iron.

Plasma has the important function of maintaining the pH of the blood at approximately 7.4.

Image was taken from the following web site: http://web.ncifcrf.gov/rtp/ial/eml/rbc.asp