Question 6b
State whether the component is hydrophilic or hydrophobic:
i) A – Phospholipid heads
ii) B – Phospholipid tails
iii) Darkly shaded part of protein (inside the membrane)
iv) Lightly shaded part of protein (at the surface of the membrane)
i) A – Phospholipid Head
Hydrophilic
The phospholipid head is attracted to water and faces the aqueous environment.
ii) B – Phospholipid Tails
Hydrophobic
The phospholipid tails repel water and face inward, away from the aqueous environment.
iii) Darkly Shaded Part of Protein
Hydrophobic
In membrane diagrams, the darkly shaded part of a protein usually represents the section embedded in the hydrophobic core of the phospholipid bilayer.
iv) Lightly Shaded Part of Protein
Hydrophilic
The lightly shaded part typically represents sections of the protein exposed to the aqueous environment, either inside or outside the cell.