Since it is a light-absorbing pigment, chlorophyll is called a photoreceptor. Also note that there are two types of chlorophyll: chlorophyll a and chlorophyll b. Function. Chlorophyll molecules are contained inside chloroplasts, which are the food producers of the cell found
Calcitonin has an opposite effect, as it decreases the levels of calcium in the blood. Overall, PTH has a strong effect on the blood concentration of calcium, whereas calcitonin has a more moderate effect and is not critical in helping the body maintain normal blood calcium levels.
Calcitonin is a hormone that is produced in humans by the parafollicular cells (commonly known as C-cells) of the thyroid gland. Calcitonin is involved in helping to regulate levels of calcium and phosphate in the blood, opposing the action of parathyroid hormone. It inhibits the activity of osteoclasts, which are the cells responsible for breaking down bone. 2  When bone is broken down, the calcium contained in the bone is released into the bloodstream. 3  Therefore, the inhibition of the osteoclasts by calcitonin directly reduces the amount of calcium released into the blood.