B. Because it is a dominant trait
Answer:
Ralph is looking at a vein (likely a muscular vein).
Explanation:
Of all three great types of vessel present in vertebrates (arterial, venous, lymphatic), only veins and lymphatic vessels may normally contain valves. This is an essential feature of vessels which present low pressure flow, since it ensures that such flow is unidirectional.
Since blood cells are not typically found in lymphatic vessels, the vessel in question can be assumed to be a vein.
Proteins are made of amino acids. In the cell, those amino acids are strung together as new proteins that your body can use to get reactions going. Carbohydrates also need to be balanced with fats and protein to maintaina healthy weight.
Basically, they control the rate of reactions and regulate cellular activity.
What about it? What’s the question