Question

if phospholipids are dropped in water, they can form a ball - shaped structure called a micelle. the model shows the cross section of a micelle formed by phospholipids. the micelle is surrounded by water. explain why phospholipids dropped in water form a micelle. complete the paragraph. the phospholipid heads face ▼ the water because they are ▼. the phospholipid tails face ▼ the water because they are ▼.

Explanation:

Phospholipids have a hydrophilic (water - attracting) head and a hydrophobic (water - repelling) tail. In water, the hydrophilic heads are attracted to water, so they face towards the water. The hydrophobic tails are repelled by water, so they face away from the water, which leads to the formation of a micelle structure.
For the first blank (direction of heads): "towards" because the heads are hydrophilic (water - loving), so they interact favorably with water.
For the second blank (property of heads): "hydrophilic" (or "water - loving") as this is the characteristic of the phospholipid heads that makes them face water.
For the third blank (direction of tails): "away from" because the tails are hydrophobic (water - hating), so they avoid water.
For the fourth blank (property of tails): "hydrophobic" (or "water - hating") as this is the characteristic of the phospholipid tails that makes them face away from water.

Answer:

The phospholipid heads face $\boldsymbol{\text{towards}}$ the water because they are $\boldsymbol{\text{hydrophilic}}$.
The phospholipid tails face $\boldsymbol{\text{away from}}$ the water because they are $\boldsymbol{\text{hydrophobic}}$.