Red blood cells are very small which allows them to pass through narrow capillaries, they have a biconcave shape which increases surface area allowing oxygen to be diffused more effectively, they contain haemoglobin which binds with the oxygen, and they do not contain a nucleus which leaves more space inside to hold more haemoglobin.
Nerve cells are very long to enable them to deliver messages long distances, they have synapses at the end of each cell to make sure the message can go in only one direction, and they have a myelin sheath which increases the thickness of the cell and makes the electrical impulse "jump" thus increasing the speed the messages are sent at.
Hope this helps :-)
The thyroid gland regulates the body's metabolism (through T3 and T4) and also affects the metabolism of calcium through the production of calcitonin, which reduces calcium concentration of the blood.
The parathyroid glands, which are located within the thyroid gland, also affect the metabolism of calcium by producing parathyroid hormone PTH, which increases calcium concentration of the blood.
It might be carbaminohemoglobin or just hemoglobin. Hemoglobin can bind to 4 molecules of carbon dioxide and transport them back to the lungs.
Sorry if I’m late but I’m pretty sure it’s B! Yes