Cell theory is one of the foundations of biology. The observation of Robert Hooke,Anton Van Leeuewenhoek,Matthias Schleiden,Theodor Schwann,Rudolf Virchow, and others led to the devolepment of the cell theory.
B. essential
We cannot store up amino acids on our body, but we can have amino acids through consumption of food. These amino acids of which the body cannot make is called as essential amino acids.
<span>In marine vertebrates, the gill arches use the external gas exchange. The water holds less oxygen.
The ribs in terrestrial vertebrates have enclosed respiratory surface which is inside the body and comes as paired lungs.
Kidneys are efficient in excretion of regulation of water and nitrogenous wastes. Their reproduction is normally sexual with separate sexes.</span>
A test that combines radioactive chemicals and antibiotics to detect minute quantities of substance in a patient's blood is RBC nuclear scan.
It used small amounts of radioactive material that is marked as tag and red blood cell as RBC's. After this your body will be scanned to see the cells and tracking the movement of body.
This process firstly removing blood from a vein. Then RBC are separated from the rest of the blood. After this the cells are mixed with radioactive material. After a short time, the tagged RBC are injected into your veins.
Veins is a tube like structure that forms part of blood circulation system of the body, that carrying oxygen-depleted blood.
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