Answer:
The blood in the pulmonary artery is going to the heart to collect oxygen, and therefore has a low content of oxygen. So, the blood in the pulmonary artery is a violet colour because it has low oxygen. The blood in the pulmonary vein is oxygen rich, and so it gives a scarlet color.
The three kind of landforms found on Earth are mountains<span>, </span>plains<span> and </span>plateaus<span>.
hope this helps :D</span>
Cell wall - protects and shapes the cell
Although it has recently been shown that certain bacteria are capable of dramatically changing shape, pleomorphy remains a controversial concept. A well accepted example of pleomorphism is Helicobacter pylori, which exists as both a helix-shaped form (classified as a curved rod) and a coccoid form.
The correct answer is by using the antagonist.
The antagonist is a molecule that blocks a biological response by binding to the receptor. So, you add antagonists to the receptors you want to determine and see which antagonist blocked the response. By blocking the specific response you can get the answer what receptor it was.
