Describe how phospholipids are arranged in the cell membrane

The phospholipids are arranged in two layers, called a phospholipid bilayer.

A phospholipid is a kind of lipid molecule that is the principal component of the cell membrane. Lipids are molecules that comprise fats, waxes, and some vitamins, among others. Every phospholipid is composed of two fatty acids, a phosphate group, and a glycerol molecule. While many phospholipids line up, they create a double layer that is characteristic of all cell membranes. They have hydrophobic tails and hydrophilic heads The hydrophilic heads are to the outside and the tails to the inside.

the correct answer is: b. pantala flavescens, because these organisms would have a high level of genetic variation due to sexual reproduction.  

because involves two organisms (parents) whose genetic material combines, sexual reproduction leads to genetic variation in new generations of offspring. the offspring is an unique organism, with new genome, more protected with the higher ability to adapted. this process is fundamental to evolution.