Question

question ①
why does the phospholipid bilayer form the way it does?
answer
○ because the phospholipid tails are composed of lipids and are hydrophilic while the heads are hydrophobic
○ because the phospholipid heads are hydrophilic and the tails are composed of lipids which are hydrophobic
○ because the phospholipid heads are composed of lipids and are hydrophobic while the tails are hydrophilic
○ because the phospholipid tails are hydrophobic while the heads are hydrophilic and composed of lipids
○ i dont know yet

Explanation:

To determine the correct answer, we analyze the structure of a phospholipid. A phospholipid has a hydrophilic (water - attracting) head and hydrophobic (water - repelling) tails. The tails are composed of lipid chains. Let's evaluate each option:

• Option 1: Incorrect. Phospholipid tails are hydrophobic, not hydrophilic, and heads are hydrophilic, not hydrophobic.
• Option 2: Correct. Phospholipid heads are hydrophilic (attracted to water), and the tails are made of lipids which are hydrophobic (repelled by water). This arrangement causes the bilayer to form with heads facing the aqueous environment and tails facing inward.
• Option 3: Incorrect. Heads are not composed of lipids in the way this option describes, and the hydrophilic/hydrophobic labels are reversed.
• Option 4: Incorrect. Tails are hydrophobic, and heads are not composed of lipids in the way stated, and the hydrophilic/hydrophobic labels are incorrect.
• Option 5: Not a valid answer as we can determine the correct one.

Answer:

B. Because the phospholipid heads are hydrophilic and the tails are composed of lipids which are hydrophobic