Question

1. sketch a diagram of the cell membrane. label the following: (4 marks)

• phospholipid bilayer
• phospholipid
• hydrophilic head
• hydrophobic tail
• channel protein
• carrier protein
• cytoplasm
• extracellular fluid
• carbohydrate chain

Explanation:

A cell membrane diagram typically shows a phospholipid bilayer with phospholipids having hydrophilic heads facing outward (towards the cytoplasm and extracellular fluid) and hydrophobic tails facing inward. Channel and carrier proteins are embedded in the bilayer for transport. Carbohydrate chains are often attached to proteins or lipids on the extracellular side. The cytoplasm is inside the membrane and extracellular fluid is outside.

Answer:

A hand - drawn or computer - generated diagram should be created with labels for phospholipid bilayer, phospholipid, hydrophilic head, hydrophobic tail, channel protein, carrier protein, cytoplasm, extracellular fluid, and carbohydrate chain. The phospholipid bilayer forms the basic structure of the membrane. Phospholipids have a head and two tails. Hydrophilic heads are polar and interact with water, while hydrophobic tails are non - polar. Channel and carrier proteins facilitate the movement of substances across the membrane. The cytoplasm is the jelly - like substance inside the cell and extracellular fluid is outside the cell. Carbohydrate chains are involved in cell recognition.