Answer:vitamin Y and vitamin Z are the essential nutrients.
Explanation:
When the researcher treated the mouse cells in the absence of vitamin W and X, the cells survived but when he eventually removed vitamin Y and Z the cells died. This implies that for the cells to grow and survive Vitamin Y and Z which are the essential Vitamin needs to be present. Thanks alot. I hope it helps!
Answer:
Bones
Explanation:
The integumentary system is the skin. You have erector pilli muscles, blood vessels and nerves all within the skin. But not bone
Answer:
The baby starts breathing
Explanation:
While in the womb, a fetus has its oxygen delivered to it, and the waste products removed (all via the mother's bloodstream), so there is no reason to separate all the chambers of the heart while still in the womb.
However, once the baby is born and it is breathing, the chambers need to differentiate in order to allow the blood to reach the lungs, and the oxygenated blood and deoxygenated blood do not mix.