Answer:
A
Explanation:
Quaternary structure of proteins is composed of two or more polypeptide chains. Insulin has two; one alpha and one beta chain. The two chains are joined together by disulfide bonds at two points (at cysteines). Other examples of quaternary proteins structures are DNA polymerase and hemoglobin.
The Answer to your question would be A
BRASS :It is easy to form into various shapes, a good conductor of heat, and generally resistant to corrosion from salt water. 1 pipes and 2 tubes, 3 screws, 4 cartridge casings for firearms.
BRONZE :for bearings because of its friction properties, and as 1 musical instruments ,2 and medals
Sulphur :1 making car batteries, 2 fertilizer
IODINE :1 Iodine regulates skin moisture levels and aids in the healing of cuts and scars through cellular regeneration. 2 Iodine also regulates the hormones responsible for acne breakouts.3 Treating thyroid cancer.
Explanation:
32
2H
2
+O
2
→2H
2
O
Molecular mass of H
2
=2 g/mol
Molecular mass of O
2
=32 g/mol
From the balanced chemical equation,
2×2=4 g of hydrogen requires 32 g of Oxygen to react completely
