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.
3. Pay attention to where your knees are. During squats or lunges, your knees should never go over your toes. Overextending your knees can lead to knee injury, because you are supporting your body with your knee joint, rather than your buttocks and thigh muscles.4. Do cardiovascular exercise daily, if you want to lose weight in your hips, thighs and butt.. Pay attention to where your knees are. During squats or lunges, your knees should never go over your toes. Overextending your knees can lead to knee injury, because you are supporting your body with your knee joint, rather than your buttocks and thigh muscles.