Formed Elements

7.5 um in diameter

anucleate with no organelles

like bags of hemoglobin

biconcave shape maintained by spectrin net which is deformable...makes RBC flexible

picks up oxygen in lungs and releases it to tissue cells

transports @20% of CO2 from tissues to lungs

gas transport functions

1. small size and shape provide huge surface area relative to volume: suited for gas exchange

2. over 97% hemoglobin which binds to and transports respiratory gases

they generate ATP by anaerobic mechanisms so they don't use up the osygen they are carrying...efficient carriers!

F: 4.3-5.2 mill per microliter

M: 5.1-5.8 mill per microliter

as RBC Inc. viscosity rises and blood flows slowly...etc.