When testing a person's skin for allergens using patch testing, tiny amounts of allergens are placed on stainless steel discs and applied to the back. how many hours later is the skin under the discs assessed for reaction?

The correct answer is - 48 hours.

Explanation:

Skin patch testing is the process or the testing method that is used to detect allergic dermatitis an individual person could be affected of from the atmosphere around him. In this test the patch with substances to test, in a small discs to skin of a person.

The test substances to the skin under the disc that are then left in place for 48 hours. The skin is then assessed a further 48 hours later for any allergic reaction.

Thus, the correct answer is - 48 hours.

Explanation:

The respiratory system brings oxygen into the lungs when you breathe. The digestive system breaks food down into nutrients such as glucose. ... The circulatory system also transports oxygen from the lungs to the cells. Now the cells have what they need for cellular respiration: oxygen and glucose