Explain 2 adaptations of red blood cells.

Biconcave shape- Increases the surface area of the red blood cell, meaning there is a greater surface over which diffusion of the gases being exchanged can occur (CO2/ O2).No nucleus- Allows red blood cells to store more haemoglobin, (the protein which is able to bind to oxygen molecules) allowing more oxyhemoglobin to form at the lungs, and more oxygen to be transported around the body to areas of high respiratory rate that are requiring more oxygen.