Edexcel GCSE Computer Science (1CP2) Exam Questions

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

• A program/set of instructions (1)
• That is being run/executed (1)
• That has been loaded into RAM/main memory to be run (1)
• That the operating system manages/schedules (1)

Allow 'task' as a synonym for process.

Accept 'executed by the CPU'; naming the CPU is not required.

For 'loaded into RAM/main memory', the answer must say the program is there to be run/executed; saying only that it is 'stored in memory' earns no mark.

Do not accept 'a program'/'a set of instructions' on its own as a full definition; it earns the first mark only.

Do not accept a program stored on secondary storage/a hard disk that is not running.

Do not accept a description of the CPU or the fetch-decode-execute cycle.

Do not accept 'a thread' as a definition of a process.

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

• File management (1)
• Process management (1)
• Peripheral management (1)
• User management (1)

Allow 'managing files', 'managing processes', 'managing peripherals', 'managing users'.

Do not accept examples of utility software, such as anti-malware, backup or defragmentation, as these are not functions of the operating system.

Do not accept 'runs/loads the programs' on its own.

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

• Reduces the file size / uses less storage space (1)
• Takes less time to upload/download/send (1)
• Uses less bandwidth / reduces the amount of data transferred (1)
• The file is more likely to fit within an email attachment size limit (1)
• Reduces the amount of storage needed for backups / more files can be stored on backup media (1)

Do not award both 'reduces the file size' and 'uses less storage space' as two separate benefits.

Do not award both 'takes less time to send' and 'uses less bandwidth' as two separate benefits.

Do not accept 'it is compressed' on its own.

Do not accept 'it makes the file easier to send' unless a benefit such as a smaller file or less time is given.

Do not accept 'better quality'.

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

• Scans files/downloads/the computer/system for malware (1)
• Compares files/code against a database of known malware/signatures/definitions (1)
• Quarantines/removes/deletes infected/suspicious files/malware (1)
• Prevents/blocks malware from running/being installed (1)
• Updates the database of malware definitions/signatures (1)

Allow removes/deletes malware for the quarantines/removes bullet.

Do not award both quarantining and removing infected files as two separate functions; they are one function.

Do not award both scanning and preventing/blocking malware if the answer describes real-time scanning that blocks malware; award one only.

Do not accept protects the computer on its own.

Do not accept defragments the disk or backs up files.

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

• Existing data would be lost (1) because the new file would overwrite/replace its contents (1)
• The original file could not be recovered (1) because its contents would be destroyed/replaced (1)
• A program that uses the existing file would fail (1) because the file's data would have been changed/removed (1)
• The user could lose important work (1) because the old file is replaced by the new one (1)

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

Do not accept 'so files do not have the same name' without a reason linked to loss of data.

Do not accept 'to keep files tidy' or 'so the computer does not crash' without a reason linked to the existing file's contents being lost.

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

• The user can identify what is in a file without opening it (1) because the name describes the contents (1)
• The user can search for a file using words from its name (1) because the file manager/search matches those words to the stored file name (1)
• The user can choose the correct file from several similar files (1) because the descriptive name distinguishes it from the other files (1)
• The user can sort/group related files together (1) because files with similar contents can share a word/phrase in their names (1)

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

A correct point on its own can award 1 mark.

Do not accept 'it is easier to find' on its own without a linked reason that says the search/file manager uses words/terms in the file name to match the search.

Do not accept 'it is organised better' unless it is linked to how the name helps, e.g. sorting/grouping files by a shared word in their names.

Do not accept 'it is more secure' or 'the file opens faster' or 'it saves storage space' because a descriptive name does not make a file more secure, open faster or take less storage.

Do not award a second mark for repeating the same benefit, e.g. saying time is saved after saying the contents can be identified without opening the file.

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

• The operating system keeps a record of where each file is stored (1) so files can be found/retrieved later (1)
• The operating system keeps files in separate storage locations (1) so files are not overwritten/lost (1)
• The operating system allocates files to folders/directories (1) so it can keep track of the files stored on the disk (1)
• The operating system deletes/moves files (1) so storage space is freed/reused (1)

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

Do not accept 'it manages files'/'it organises files' without expansion as to what is managed or organised.

Do not accept 'so files are managed/organised' as the linked reason.

Do not accept 'so the computer works' as the linked reason.

Indicative content

Saving files

• When saving, the operating system lets the student choose the folder and the file name, so new work goes into the correct subject folder instead of the root.
• The operating system warns the student before a file with the same name is overwritten, so an earlier version of an essay is not lost by accident.
• The operating system writes the file into free space on the laptop and records where it is, so the student can open it again later.

Deleting files

• The operating system lets the student delete files that are no longer needed, which frees space so new photographs can be saved.
• Deleted files are usually moved to the recycle bin first, so a file removed by mistake can be restored.
• Emptying the recycle bin removes the data permanently and releases the space for other files.

Copying files

• The operating system lets the student copy files to a USB flash drive, so there is a second copy if the laptop is lost or damaged.
• Copying leaves the original file in place, so the student can carry on working on the laptop's copy.
• A whole folder can be copied in one action, including its subfolders, which is quicker than copying each file separately.

Levels

• Level 0 (0 marks): No rewardable content.
• Level 1 (1–2 marks): Basic, independent points are made, showing elements of understanding of key concepts/principles of computer science. (AO1) The discussion will contain basic information with little linkage between points made or application to the context. (AO2)
• Level 2 (3–4 marks): Demonstrates adequate understanding of key concepts/principles of computer science. (AO1) The discussion shows some linkages and lines of reasoning with some structure and application to the context. (AO2)
• Level 3 (5–6 marks): Demonstrates comprehensive understanding of key concepts/principles of computer science to support the discussion being presented. (AO1) The discussion is well developed, with sustained lines of reasoning that are coherent and logically structured, and which clearly apply to the context. (AO2)

Level 3 responses must cover saving, deleting and copying.

Do not accept answers about the processor or defragmentation as file management tasks.

Indicative content

How the CPU is shared between processes

• The operating system uses multitasking to give each process a short time slice on the CPU, so the music, video editor and download appear to run at the same time.
• The operating system decides which ready process will run next, so one program cannot keep the CPU to itself.
• The operating system can stop a running process and move it back to ready when its time slice ends, so all processes make progress.

The states a process can be in

• When a program is opened, the operating system creates a process and moves its instructions into RAM so it is ready.
• The operating system moves a ready process to running when the CPU is free.
• A running process becomes blocked when it is waiting for input or data, such as the download waiting for data to arrive.
• When the process finishes, the operating system terminates it and releases the resources it was using.

How the operating system responds when a process needs attention

• An interrupt is a signal to the CPU that needs immediate attention, so the operating system suspends the current process and runs the interrupt handler.
• A hardware interrupt could be a printer out of paper, and a software interrupt could be an error in a program.
• After the interrupt has been handled, the operating system can return the interrupted process to the CPU.

Levels

• Level 0 (0 marks): No rewardable content.
• Level 1 (1–2 marks): Basic, independent points are made, showing elements of understanding of key concepts/principles of computer science. (AO1) The discussion will contain basic information with little linkage between points made or application to the context. (AO2)
• Level 2 (3–4 marks): Demonstrates adequate understanding of key concepts/principles of computer science. (AO1) The discussion shows some linkages and lines of reasoning with some structure and application to the context. (AO2)
• Level 3 (5–6 marks): Demonstrates comprehensive understanding of key concepts/principles of computer science to support the discussion being presented. (AO1) The discussion is well developed, with sustained lines of reasoning that are coherent and logically structured, and which clearly apply to the context. (AO2)

Additional guidance

• Level 3 responses must cover at least two of scheduling, process states and interrupts.
• A response that only states that the OS 'manages processes' or gives a program a turn, without expansion, is limited to Level 1.

Indicative content

How malware could affect the charity's computers

• A virus could damage or delete the charity's files, such as its records of donations.
• Spyware could record keystrokes and send staff passwords or personal data to a hacker.
• A Trojan horse could hide malicious code inside a useful-looking program that a volunteer downloads, so it is installed without the user knowing.
• Malware could spread from one laptop to another through files shared on the charity's network, so more laptops become infected and more files are lost.

How anti-malware software finds and deals with malware

• It scans files and compares their code with a database of known malware patterns (signatures) to identify a match.
• It can apply rules (heuristics) to decide whether a program is behaving suspiciously.
• A suspicious file can be run in a sandbox to see whether its behaviour is malicious.
• When malware is found, the file is quarantined so that it cannot run, and it can be deleted.
• Downloads and email attachments can be scanned before a member of staff opens them.

What else the charity must do for the anti-malware software to be effective

• The database of malware definitions must be kept up to date, or new malware will not be recognised.
• Staff and volunteers should be trained not to open unexpected attachments or download from unreliable sites.
• Backups are still needed, because anti-malware cannot repair files that malware has already damaged.
• Scheduled scans must be allowed to run on all 15 laptops, so that malware is found even if no one opens the file.

Levels

• Level 0 (0 marks): No rewardable content.
• Level 1 (1–2 marks): Basic, independent points are made, showing elements of understanding of key concepts/principles of computer science. (AO1) The discussion will contain basic information with little linkage between points made or application to the context. (AO2)
• Level 2 (3–4 marks): Demonstrates adequate understanding of key concepts/principles of computer science. (AO1) The discussion shows some linkages and lines of reasoning with some structure and application to the context. (AO2)
• Level 3 (5–6 marks): Demonstrates comprehensive understanding of key concepts/principles of computer science to support the discussion being presented. (AO1) The discussion is well developed, with sustained lines of reasoning that are coherent and logically structured, and which clearly apply to the context. (AO2)

Level 3 responses must cover both how malware could affect the computers and how anti-malware software finds or deals with it; a brief deal-with point and an unexplained update point, with no identification method and no effect on the charity's files, are Level 1.

Do not accept anti-malware software described as a firewall, or 'scans files'/'finds viruses' on its own as a method of identifying malware.