Answer:
Hemoglobin.pulmonary artery.
Explanation:
1. about hemoglobin.Hemoglobin is the protein inside red blood cells. It carries oxygen.
2. about pulmonary artery.The pulmonary artery is a big artery that comes from the heart. It splits into two main branches, and brings blood from the heart to the lungs. At the lungs, the blood picks up oxygen and drops off carbon dioxide. The blood then returns to the heart through the pulmonary veins.
3. There exist a concentration difference of carbon dioxide and oxygen inside the alveoli and capillaries due to which the diffusion of the two gases takes place. The carbon dioxide moves from the blood to the alveoli sac and the oxygen moves from the sacs to the blood.
Answer: What's your answer?
Explanation:
<span>Basically, the body needs to know what it is defending against. Your body can still (usually) fight off infection, even without an immunization, but it takes longer. Basically, your body creates cells with a receptor for a specific disease. When this cell finds the disease it is programmed for, it will send out signals to the "killer" cells to come and kill it. If your body doesn't have the "seeker" cells, it can't fight off the infection until it does. The opposite end are autoimmune diseases, where your immune system starts attacking itself.
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