With regard to the functioning of the thyroid gland, which is an essential element for the manufacturing of thyroxine and triiodothyronine?

The correct answer is- iodine

Explanation:

Thyroid glands is an important endocrine gland of the body which release hormone called thyroid hormone in the blood. It plays an important role in metabolism, brain development, and function, muscle control, etc.

The active form of thyroxine is triiodothyronine and the formation of thyroid hormone requires the availability of iodine. Four iodine atoms are present in thyroxine and 3 is present in triiodothyronine. Without iodine, they can not be produced.  

Therefore iodine is the essential element that is required for the manufacturing of thyroxine and triiodothyronine.

b is dominant over the allele for the white fur.

the food storage products of chrysophytes are oils or the polysaccharide laminarin.   formerly classified as plants, the chrysophytes contain the photosynthetic pigments chlorophyll a and c all but the yellow-green algae also contain the carotenoid pigment fucoxanthin.