A male and female, sperm and egg.
They are sandwiched between two layers of heads. Recall that the heads are hydrophilic therefore they will always be on the outside and the tails are hydrophobi therefore they willl always be away from water, there fore sandwiched. I'm a bio major, hope I helped :)
Your cardiovascular system is what moves blood through your body, delivering oxygen, nutrients, and more to its many cells. Those veins and arteries keep you alive. In your home, there are pipes that deliver water to different rooms of the house, helping you stay clean and hydrated.
