Answer:
Second choice is the right one.
It is caused by <span>Carbon dioxide, Ozone, Methane and Water vapor!</span>
The answer is B. Carbon atoms can bond to other carbon atoms. In fact, carbon has four electrons to form four bonds with other atoms, including carbon. Carbon is the most common and used element in the world because it makes up all living things. All four main macromolecules also contain carbon.
Answer:
Explanation:
Key developments in blood transfusion techniques
• Animal experiments over the years 1900-1916 gradually enabled transfusion to become the routine technique it is today. The key developments were:
• George Crile (1907) perfected the technique of transfusion from artery to vein using dogs, and described its application in 32 patients.
• Hustin (1914) showed that addition of sodium citrate could prevent blood from clotting and that citrated blood could be safely transfused into dogs.
• Richard Lewisohn (1915) determined the maximum amount of citrate that could be transfused into dogs without toxicity and thus determined the optimum concentration that could be added to blood for the best anticoagulant effect.
• Weil (1915) showed that citrated blood could be stored for 2 days and still be effective when transfused into guinea-pigs and dogs which had lost blood.
• Rous and Turner (1916) used rabbits to demonstrate that, with certain additives and proper treatment, citrated blood could be stored for 14 days and still be successfully transfused.
Through these animal experiments, the prolonged storage of blood without clotting thus became possible, so enabling the establishment of blood banks, and blood transfusion as a routine procedure.
