A-LEVEL AQA COMPUTER SCIENCE PAPER 2
FINAL EXAM 2025 WITH CORRECT ANSWERS
QUESTIONAccumulator - answer-Stores results of calculations in the ALU
QUESTIONProgram Counter (PC) - answer-Holds memory address of the instruction for each cycle
QUESTIONFetch - answer-The next instruction is retrieved by CPU from main memory
QUESTIONDecode - answer-The instruction is broken down and decided so computer can understand
QUESTIONExecute - answer-The CPU performs what the instructions told
QUESTIONEmbedded System - answer-A computer system built within a large device e.g. Camera, washer,
car
Arithmetic Logic Unit (ALU) - answer-Performs operations on data e.g. Addition, subtraction
QUESTIONControl Unit (CU) - answer-Coordinating activities of the CPU
QUESTIONRegisters - answer-Quick, small stores of data within the CPU
QUESTIONMemory Address Register (MAR) - answer-Holds memory address for data or a instruction about
to be used by the CPU
QUESTIONMemory Data Register (MDR) - answer-Holds actual data or instruction
QUESTIONVolatile - answer-Memory loses its data when power of
QUESTIONNon-volatile - answer-Memory retains its data when power is lost
QUESTIONRandom Access Memory (RAM) - answer-Read/write - function is to load open programs and
operating system data currently in use - volatile
QUESTIONRead Only Memory (ROM) - answer-Can only be read, can't be changed, stores essential
programs to be run in order to boot the computer - non-volatile
,QUESTIONCache - answer-A type memory that stores copies of frequently used data, much faster than RAM,
lower capacity - closer to CPU
QUESTIONBuses - answer-Collection of wires that carry signals between various components of the
computer system
QUESTIONCentral Processing Unit (CPU) - answer-Processes all of the data and instructions that make the
system work - can be effected by clock speed, number of cores, cache size
QUESTIONClock speed - answer-How fast the computer does the FDE cycle
QUESTIONCloud stotage - answer-Data is stored on multiple servers in a remote location
ADV: secure, can be accessed anywhere, no need to buy
DIS: needs internet, download and upload can be effected by internet connection, less control if data is held
QUESTIONOperating System - answer-essential software that links the hardware and other software together
and generally manages the computer system
QUESTIONCommand-line Interface - answer-Text commands where user has to type in command
QUESTIONGraphical User Interface (GUI) - answer-uses icons and other visual indicators to navigate and
issue commands
QUESTIONUtility Software - answer-maintains a computer
QUESTIONDefragmentation Software - answer-reorganises data on the hard drive to put fragmented files
back together and moves files to collect all the free space
QUESTIONBackup Software - answer-Full Backup - a copy is taken from from every file on the system
Incremental Backup - only files created or edited since last backup are copied
QUESTIONCompression Software - answer-reduces file size so they take up less space on hard disk
QUESTIONEncryption Software - answer-scrambles data to stop others from accessing it
QUESTIONOpen Source Software - answer-source code is made freely available and users can modify it
ADV: free, ,made for greater good, can be adapted
DIS: small, buggy, security holes, no warranties, no customer support
QUESTIONProprietary Software - answer-only the compiled code is released and the source code is kept a
secret
, ADV: warranties, well-tested, reliable, cheaper
DIS: expensive, software may not fit user needs
QUESTIONPersonal Area Network (PAN) - answer-within the range of an individual person
QUESTIONLocal Area Network (LAN) - answer-a network that connects devices close to each other e.g.
school, house
QUESTIONWide Area Network (WAN) - answer-a network within a large geographical area e.g. internet
QUESTIONBandwidth - answer-amount of data that can be transferred in a given time
QUESTIONNetwork Interface Card (NIC) - answer-allow a device to connect to a network
QUESTIONSwitch - answer-connect devices on a LAN
QUESTIONRouter - answer-responsible for transmitting data between networks
QUESTIONEthernet - answer-a set of standards for connecting computers
QUESTIONClient-server Network - answer-client has connection to server, servers can backup and store
centrally but can be expensive and difficult to maintain
QUESTIONPeer-to-peer Network - answer-no central server, each computer equal in responsibility, have to
work as both server and a client.
QUESTIONStar Topology - answer-ADV: better performance, rest of network not affected in one fails, simple
to add more devices
DIS: wire needed for all devices, expensive
QUESTIONMesh Topology - answer-ADV: faster
DIS: expensive
QUESTIONMAC Address - answer-assigned to all devices, unique to all devises and cannot be changed,
permanent, identifies the actual device.
QUESTIONIP Adress - answer-assigned either manually or automatic, the location of your device on the
internet
FINAL EXAM 2025 WITH CORRECT ANSWERS
QUESTIONAccumulator - answer-Stores results of calculations in the ALU
QUESTIONProgram Counter (PC) - answer-Holds memory address of the instruction for each cycle
QUESTIONFetch - answer-The next instruction is retrieved by CPU from main memory
QUESTIONDecode - answer-The instruction is broken down and decided so computer can understand
QUESTIONExecute - answer-The CPU performs what the instructions told
QUESTIONEmbedded System - answer-A computer system built within a large device e.g. Camera, washer,
car
Arithmetic Logic Unit (ALU) - answer-Performs operations on data e.g. Addition, subtraction
QUESTIONControl Unit (CU) - answer-Coordinating activities of the CPU
QUESTIONRegisters - answer-Quick, small stores of data within the CPU
QUESTIONMemory Address Register (MAR) - answer-Holds memory address for data or a instruction about
to be used by the CPU
QUESTIONMemory Data Register (MDR) - answer-Holds actual data or instruction
QUESTIONVolatile - answer-Memory loses its data when power of
QUESTIONNon-volatile - answer-Memory retains its data when power is lost
QUESTIONRandom Access Memory (RAM) - answer-Read/write - function is to load open programs and
operating system data currently in use - volatile
QUESTIONRead Only Memory (ROM) - answer-Can only be read, can't be changed, stores essential
programs to be run in order to boot the computer - non-volatile
,QUESTIONCache - answer-A type memory that stores copies of frequently used data, much faster than RAM,
lower capacity - closer to CPU
QUESTIONBuses - answer-Collection of wires that carry signals between various components of the
computer system
QUESTIONCentral Processing Unit (CPU) - answer-Processes all of the data and instructions that make the
system work - can be effected by clock speed, number of cores, cache size
QUESTIONClock speed - answer-How fast the computer does the FDE cycle
QUESTIONCloud stotage - answer-Data is stored on multiple servers in a remote location
ADV: secure, can be accessed anywhere, no need to buy
DIS: needs internet, download and upload can be effected by internet connection, less control if data is held
QUESTIONOperating System - answer-essential software that links the hardware and other software together
and generally manages the computer system
QUESTIONCommand-line Interface - answer-Text commands where user has to type in command
QUESTIONGraphical User Interface (GUI) - answer-uses icons and other visual indicators to navigate and
issue commands
QUESTIONUtility Software - answer-maintains a computer
QUESTIONDefragmentation Software - answer-reorganises data on the hard drive to put fragmented files
back together and moves files to collect all the free space
QUESTIONBackup Software - answer-Full Backup - a copy is taken from from every file on the system
Incremental Backup - only files created or edited since last backup are copied
QUESTIONCompression Software - answer-reduces file size so they take up less space on hard disk
QUESTIONEncryption Software - answer-scrambles data to stop others from accessing it
QUESTIONOpen Source Software - answer-source code is made freely available and users can modify it
ADV: free, ,made for greater good, can be adapted
DIS: small, buggy, security holes, no warranties, no customer support
QUESTIONProprietary Software - answer-only the compiled code is released and the source code is kept a
secret
, ADV: warranties, well-tested, reliable, cheaper
DIS: expensive, software may not fit user needs
QUESTIONPersonal Area Network (PAN) - answer-within the range of an individual person
QUESTIONLocal Area Network (LAN) - answer-a network that connects devices close to each other e.g.
school, house
QUESTIONWide Area Network (WAN) - answer-a network within a large geographical area e.g. internet
QUESTIONBandwidth - answer-amount of data that can be transferred in a given time
QUESTIONNetwork Interface Card (NIC) - answer-allow a device to connect to a network
QUESTIONSwitch - answer-connect devices on a LAN
QUESTIONRouter - answer-responsible for transmitting data between networks
QUESTIONEthernet - answer-a set of standards for connecting computers
QUESTIONClient-server Network - answer-client has connection to server, servers can backup and store
centrally but can be expensive and difficult to maintain
QUESTIONPeer-to-peer Network - answer-no central server, each computer equal in responsibility, have to
work as both server and a client.
QUESTIONStar Topology - answer-ADV: better performance, rest of network not affected in one fails, simple
to add more devices
DIS: wire needed for all devices, expensive
QUESTIONMesh Topology - answer-ADV: faster
DIS: expensive
QUESTIONMAC Address - answer-assigned to all devices, unique to all devises and cannot be changed,
permanent, identifies the actual device.
QUESTIONIP Adress - answer-assigned either manually or automatic, the location of your device on the
internet
