Answer:
Hydronium ion is not an electrophile because, its positive charge is on oxygen and its octet is filled.
Explanation:
The phosphate group contribute the following functional features to the structure of phospholipids:
1. Negative charge to interact with water.
2. Place to attach another small molecule.
The phosphate group is made up of four atoms of oxygen which are attached to one atom of phosphorus. This molecule has a net negative charge of -3. In the phospholipid molecule, the phosphate enhanced the polarity of the phospholipid head by mean of its negative charge which react with water. Phosphate group also provide a point where other small molecules such as alcohol, serine, etc can be attached.
Endothermic reaction is the reaction in which the system absorbs energy. The system absorbs heat and cools the surroundings. Reactants are the substances that are involved in the reaction and at the end of the reaction product are formed.
In the endothermic reaction because heat is absorbed , the products have a higher heat.
I would say because the respiratory system brings in the oxygen for the body and the circulatory system moves it throughout the body with the blood