Edexcel GCSE Computer Science (1CP2) Exam Questions

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

• The program (and its data) is copied/loaded from secondary storage into main memory/RAM (1) so that the CPU can fetch/execute its instructions (1)
• An area of main memory is allocated/reserved for the program (1) that is large enough to hold the program and its data (1)
• The operating system checks that there is enough free main memory (1) before the program can be started/loaded, otherwise it cannot run/an error is reported (1)
• The operating system keeps a record of the memory addresses used by the program (1) so that its instructions and data can be found when it runs (1)

Allow 'loaded into RAM', 'stored in memory' and 'put into main memory' as equivalent to copied into main memory.

A single statement that the program is loaded/stored in main memory, with no linked development, can be given one mark only.

Do not accept descriptions of the CPU fetching/executing instructions that do not refer to the operating system loading or allocating memory.

Do not accept responses about virtual memory (moving processes to secondary storage) or about which process runs next on the CPU.

Do not accept the program being run from secondary storage/hard disk.

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

• The operating system switches rapidly between processes (1) so each process runs for a short time slice before the next one starts (1)
• Each process is given a small amount of CPU time (1) so the CPU moves on to another process when that time is up (1)
• The operating system chooses which process to run next (1) so the CPU is shared between the programs (1)
• Processes take turns to use the CPU (1) because the CPU is so fast the user does not notice the switching (1)
• Only one process can run on the CPU at a time (1) so the operating system must swap processes in and out quickly (1)

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

Allow 'time slice' / 'time quantum'.

Do not accept 'the computer has more than one CPU' / 'each program runs on its own CPU'.

Do not accept 'the CPU does two things at once' without saying processes take turns/are switched.

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

• Lost/damaged files can be restored (1) because a copy is stored separately from the original (1)
• Data can be recovered after a hardware failure (1) because a duplicate copy is kept on another storage device/location (1)
• Files can be recovered if they are deleted by accident (1) because a copy was made before they were deleted (1)
• A previous version of a file can be recovered (1) because backups are made regularly/at set times (1)

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

A benefit stated on its own, such as 'lost files can be restored', earns the first mark only.

Do not accept a description of what backup software does, such as 'it makes a copy of the files' or 'it backs up files', without a benefit it provides.

Do not accept 'keeps data safe' or 'stops files being lost' on its own without saying how the data can be recovered.

Do not accept protection from malware/viruses, e.g. 'it protects the computer from viruses'; that is the purpose of anti-malware software.