The exchange of gases (O2 & CO2) between the alveoli & the blood occurs by simple diffusion: O2 diffusing from the alveoli into the blood & CO2 from the blood into the alveoli. Diffusion requires a concentration gradient. in the alveoli must be kept at a lower lever than in the blood. We do this, of course, by breathing - continuously bringing fresh air (with lots of O2& little CO2) into the lungs & the alveoli. Breathing is an active process - requiring the contraction of skeletal muscles.
Quick Answer. During a rooster injection on a knee, the doctor cleans an injection site near the kneecap, inserts a needle and withdraws any extra fluid from the knee area, and then through the same needle injects a solution containing hyaluronic acid, a substance obtained from rooster combs, into the knee joint, according to WebMD.
The Downside to Joint Viscosupplementation Injections: 1  The downside to these types of gel injections are side-effects like itching, increased fluid, redness, rashes, stiffness, swelling, and increased knee pain and changes in gait (limping).2  Gel injections just add lubrication to the knee joint.ortisone knee injections are very effective at temporarily relieving swelling and inflammation. The Downside To Cortisone Injections: 1  Cortisone injections for knee pain will be ineffective if there is no swelling or inflammation in the knee. 2  If the area isnât numbed properly the injection can be painful.