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.
Answer:
pituitary gland
Explanation:
The endocrine system is primarily hormones. Glands of the endocrine system are the pituitary gland, the thyroid gland, the parathyroid glands, the thymus, and the adrenal glands.
Composite volcanoes (or stratovolcanoes) typical have a sloping lower side that grows steeper until it reaches the top. Its side is layered with hardened lava, mud, and ashes from previous eruptions. Its rocks may vary from basalts to rhyolite, but the usual kinds of rocks that are layered on composite volcanoes are andesitic.
When heat is applied to water, the transfer of energy causes the water molecules vibrate at a quicker pace. As the heat increases, the molecules get further apart, causing the water to change form from a liquid to a gas (aka vapor). As the molecules cool, they lose the energy from heat that was applied, causing the molecules to vibrate at a slower pace. As the energy is lost, the water molecules to come closer together, resulting in water returning to a liquid state.
Answer: It makes the soil frozen and hard
Explanation: the permafrost frezzes the soil and doesnt allow any plant life to grow