Answer: albumin
Notes: The protein responsible for the maintenance of osmotic pressure in the blood is albumin. Albumin, produced by the liver, constitutes about 60% of the total protein in plasma and plays a crucial role in regulating oncotic pressure, which helps retain fluid within the blood vessels. Low levels of albumin can lead to edema and other complications. In contrast, beta macroglobulin and gamma globulin (immunoglobulins) are involved in immune responses and do not primarily function in osmotic pressure regulation.
