Menu

Edexcel GCSE Computer Science (1CP2) Exam Questions

Build a practice paper from 604 exam-style questions, each with its mark scheme and example answers. Print it, or answer it on paper and then open the mark schemes. Or browse the questions by topic.

Build a paper

Topics (none ticked: all of them)
Question types (none ticked: all of them)

Practice paper

4 questions · 7 marks

Pick again
Print
1Multiple choice1 markFetch Decode Execute Cycle Swap Remove

Identify the CPU component that decodes instructions during the fetch-decode-execute cycle.

[1 mark]
  • AArithmetic logic unit
  • BControl unit
  • CMain memory
  • DRegister
Mark scheme
  • B Control unit (1)
  • The only correct answer is B. The correct answer is control unit.
  • A is not correct because the arithmetic logic unit performs arithmetic and logical operations, not decoding
  • C is not correct because main memory stores instructions and data, not decoding
  • D is not correct because a register holds data or addresses temporarily, not decoding
Example answers and how they were marked
Full marks1/1

B Control unit

Why: Correct option: the control unit decodes instructions (1).

No marks0/1

D Register

Why: Near-miss: a register holds data or addresses temporarily, it does not decode instructions (0).

No marks0/1

A Arithmetic logic unit

Why: Misconception: the arithmetic logic unit performs arithmetic and logical operations; it does not decode (0).

2Short recall2 marksEmbedded Systems Swap Remove

An embedded system is a computer system built into another device to perform a specific function.

Give two examples of devices that contain an embedded system.

[2 marks]
Mark scheme

Award one mark for any of the following up to a maximum of two marks:

  • Microwave (oven) (1)
  • Washing machine (1)
  • Dishwasher (1)
  • Digital camera (1)
  • Satellite navigation/satnav system (1)
  • Traffic light(s) (1)
  • Central heating controller/thermostat (1)
  • Digital watch/fitness tracker (1)
  • Vending machine (1)
  • Car (as it contains embedded systems) (1)

Allow any other device that contains an embedded system.

Do not accept general purpose devices such as a laptop, desktop computer, tablet or smartphone (these can run many different programs).

Example answers and how they were marked
Full marks2/2

A microwave oven and a washing machine.

Why: Two creditworthy devices, a microwave oven (1) and a washing machine (1).

Some marks1/2

A dishwasher and a laptop computer.

Why: Dishwasher credited (1); laptop is a general purpose device, so not accepted.

No marks0/2

A desktop computer and a smartphone.

Why: Both are general purpose devices, so neither earns a mark.

3Short recall2 marksCompression Swap Remove

Files can be compressed before they are stored.

Define the term lossless compression.

[2 marks]
Mark scheme

Award one mark for any of the following up to a maximum of two marks:

  • Reduces/makes the size of a file smaller (1)
  • No data is lost/removed (during compression) (1)
  • The original file/data can be recreated/restored exactly (1)

Allow 'the compressed file takes up less storage space' for the first mark.

The second and third bullets are two ways of making the same point: award a maximum of one mark for them, so a response that says no data is lost and that the original file can be restored, but does not say the file is smaller, scores one mark.

Do not accept descriptions of lossy compression, e.g. 'it removes data that is not needed to make the file smaller'.

Ignore reference to download/transmission times, bandwidth and streaming, as these are benefits of compression and not part of the definition.

Example answers and how they were marked
Full marks2/2

Lossless compression reduces the size of a file without permanently removing any data, so the original file can be restored exactly.

Why: Reduces the size of a file (1) and no data is lost, so the original can be restored exactly (1); maximum of two marks reached.

Some marks1/2

It makes a file smaller so it downloads more quickly.

Why: Reduces the size of a file (1); the faster download is ignored as a benefit, not part of the definition.

No marks0/2

It removes data that is not needed to make the file smaller.

Why: Describes lossy compression, which the do-not-accept line rules out, so the mention of making the file smaller is not credited.

4Explain2 marksProtocols & Layers Swap Remove

The TCP/IP model has four layers.

Explain one function of the transport layer when a file is sent over a network.

[2 marks]
Mark scheme

Award up to two marks for a linked explanation such as:

  • Splits the data/file into packets (1) so each packet can be sent separately across the network (1)
  • Adds a packet/sequence number to each packet (1) so the packets can be put back into the correct order at the destination (1)
  • Detects lost/missing packets (1) so they can be requested/resent (1)
  • Creates a connection between the two computers/hosts (1) before the file is sent (1)

For both marks, the expansion must follow/associate with the statement.

Allow 'segments' for 'packets' (TCP divides the data into segments, which become packets at the internet layer).

Do not accept 'sends the data/file' on its own without saying what the transport layer does to the data.

Do not accept naming TCP or a port number on its own without expansion.

Do not accept routing/addressing packets using IP addresses, which is the internet layer.

Example answers and how they were marked
Full marks2/2

The transport layer splits the data into packets (1) so each packet can be sent separately across the network (1).

Why: Linked point (1) and reason (1): splitting into packets lets each one be sent separately.

Some marks1/2

It splits the data into packets (1).

Why: Point (1) identified, but no linked reason given, so only the first mark is awarded.

No marks0/2

It routes the packets using IP addresses (0) so they reach the right destination.

Why: Routing using IP addresses is the internet layer, not the transport layer, so no credit is given.

Questions by topic

More ways to revise Edexcel GCSE Computer Science (1CP2)

Teachers: build a paper, print it with the mark schemes at the end, and sign your school up to set your classes activities on every topic.

Fetch Decode Explain isn't affiliated with or endorsed by Pearson Edexcel.