💡Hint: Think about the 'P' in CPU. It handles instructions.
✅ Mark Scheme
To process instructions or data.
To perform the Fetch-Execute cycle.
⚠️ Examiner's Trap
Do NOT say "Brain of the computer". This will get 0 marks.
Did you get it right?
1(b)[1 Mark]
The CPU follows a cycle to process data. Identify the name of this cycle.
✅ Mark Scheme
Fetch-Execute Cycle
F-E Cycle
FDE Cycle
Did you get it right?
2[4 Marks]
Complete the sentences by filling in the missing words.
The CPU stands for (drop here).
It is the part of the computer that fetches and executes the (drop here) that are stored in (drop here).
The CPU contains the Arithmetic Logic Unit (ALU) and the (drop here) Unit (CU).
Instructions
Memory
Central Processing Unit
Control
Data
✅ Mark Scheme
Central Processing Unit
Instructions (Ignore "Data")
Memory / RAM
Control
Score yourself (1 mark per correct gap):
3[3 Marks]
Indicate whether each statement is True or False.
Statement
Selection
The CPU fetches and decodes instructions.
The speed of a CPU is usually measured in Gigabytes (GB).
The hard disk drive is part of the CPU.
✅ Mark Scheme
True
False (Measured in Hz/GHz)
False (Storage is secondary, not part of CPU)
Score yourself (1 mark per correct row):
4[4 Marks]
Match each part of the processor to its correct definition. Click a box on the left, then click the matching box on the right.
💡Hint: "Logic" does maths. "Cache" is fast storage.
Control Unit (CU)
Cache
Arithmetic Logic Unit (ALU)
Register
Performs mathematical and logical operations.
Sends signals to direct the operations of the processor.
High speed memory inside the processor that stores recently used instructions.
A small piece of memory inside the processor that can hold one instruction or address.
✅ Mark Scheme
CU: Sends signals to direct operations...
Cache: High speed memory...
ALU: Performs mathematical...
Register: Small piece of memory holding one instruction...
Score yourself (1 mark per correct line):
5[2 Marks Total]
(a) Identify one register found in the Von Neumann architecture. (b) Describe the purpose of the register you identified.
✅ Mark Scheme
Part (a) - Examples:
PC (Program Counter)
MAR (Memory Address Register)
MDR (Memory Data Register)
ACC (Accumulator)
Part (b) - Must match (a):
PC: Address of next instruction.
MAR: Address of data to be fetched.
MDR: The data/instruction fetched from memory.
ACC: Results of calculations from ALU.
⚠️ Examiner's Trap
For part (b), you must say "Stores" or "Holds". Saying "It fetches" is not enough, as the register itself is just a storage location.
Score yourself (Max 2):
6[5 Marks Total]
A student sees a CPU with 3.8 GHz Clock Speed and Quad Core.
(a) Describe what is meant by a clock speed of 3.8 GHz. [2] (b) Explain why a Quad Core might not always run faster than a Dual Core. [3]
💡Hint 6a: Mention the number of cycles and "per second". 💡Hint 6b: Can all software use 4 cores? What if the Dual Core has a higher GHz?
✅ Mark Scheme
(a) Clock Speed:
3.8 billion cycles per second. (1 mark for "cycles per second", 1 mark for 3.8 billion).
(b) Cores Performance:
Software might not be designed to use multiple cores (parallel processing).
Some tasks are sequential (depend on previous tasks).
The Dual Core might have faster Clock Speed, more Cache, or RAM.
⚠️ Common Mistake
Do not say "The speed of the CPU" for clock speed. You must reference cycles per second.