GCSE COMPUTER SCIENCE OCR UPDATED EVALUATION
EXAM QUESTIONS AND ANSWERS SURE A+
✔✔parameters - ✔✔special variables used to pass values into a sub program (specify
name, data type, default value)
✔✔arguments - ✔✔actual values that parameters take when sub program called
✔✔total number of colours - ✔✔2^n (where n = number of bits per pixel)
✔✔24 bit colour depth - ✔✔average device colour depth
✔✔resolution - ✔✔density of the pixels in an image
✔✔bit rate equation - ✔✔sampling frequency x sample size
✔✔range check - input validation - ✔✔checks the data is within a specified range
✔✔presence check - input validation - ✔✔checks data has been entered
✔✔check digit - input validation - ✔✔checks numerical data has been entered
accurately
✔✔format check - input validation - ✔✔checks data has correct format
✔✔look-up table - input validation - ✔✔checks data against a table of acceptable values
✔✔length check - input validation - ✔✔checks data is correct length
✔✔syntax errors - ✔✔rules or grammar of programming language is not followed so
compiler or interpreter doesn't understand
✔✔logic errors - ✔✔when compiler or interpreter is able to run program but program
does something unexpected
✔✔diagnosing logic errors - ✔✔found through general use of program and by
systematically testing
✔✔performance test - ✔✔tests how quickly certain features run and their impact on
computer resources
✔✔usability test - ✔✔tests how user-friendly the interface and features are
✔✔security test - ✔✔tests vulnerability to attacks and how securely data is stored
, ✔✔load/stress test - ✔✔tests how it copes under extreme conditions
✔✔functionality test - ✔✔tests if program meets initial requirements
✔✔software development cycle - ✔✔requirements, design, implementation, testing,
maintenance
✔✔normal data - ✔✔data that user is likely to input
✔✔assemblers - ✔✔turn assembly language into machine code
✔✔AND - Conjunction - ✔✔e.g. A /\ B
✔✔OR - Disjunction - ✔✔e.g. A\/B
✔✔NOT - Negation - ✔✔e.g. -|A
✔✔ Arithmetic Logic Unit (ALU) - ✔✔Performs operations on data e.g. Addition,
subtraction
✔✔Control Unit (CU) - ✔✔Coordinating activities of the CPU
✔✔Registers - ✔✔Quick, small stores of data within the CPU
✔✔Memory Address Register (MAR) - ✔✔Holds memory address for data or a
instruction about to be used by the CPU
✔✔Memory Data Register (MDR) - ✔✔Holds actual data or instruction
✔✔Accumulator - ✔✔Stores results of calculations in the ALU
✔✔Program Counter (PC) - ✔✔Holds memory address of the instruction for each cycle
✔✔Fetch - ✔✔The next instruction is retrieved by CPU from main memory
✔✔Decode - ✔✔The instruction is broken down and decided so computer can
understand
✔✔Execute - ✔✔The CPU performs what the instructions told
✔✔Embedded System - ✔✔A computer system built within a large device e.g. Camera,
washer, car
EXAM QUESTIONS AND ANSWERS SURE A+
✔✔parameters - ✔✔special variables used to pass values into a sub program (specify
name, data type, default value)
✔✔arguments - ✔✔actual values that parameters take when sub program called
✔✔total number of colours - ✔✔2^n (where n = number of bits per pixel)
✔✔24 bit colour depth - ✔✔average device colour depth
✔✔resolution - ✔✔density of the pixels in an image
✔✔bit rate equation - ✔✔sampling frequency x sample size
✔✔range check - input validation - ✔✔checks the data is within a specified range
✔✔presence check - input validation - ✔✔checks data has been entered
✔✔check digit - input validation - ✔✔checks numerical data has been entered
accurately
✔✔format check - input validation - ✔✔checks data has correct format
✔✔look-up table - input validation - ✔✔checks data against a table of acceptable values
✔✔length check - input validation - ✔✔checks data is correct length
✔✔syntax errors - ✔✔rules or grammar of programming language is not followed so
compiler or interpreter doesn't understand
✔✔logic errors - ✔✔when compiler or interpreter is able to run program but program
does something unexpected
✔✔diagnosing logic errors - ✔✔found through general use of program and by
systematically testing
✔✔performance test - ✔✔tests how quickly certain features run and their impact on
computer resources
✔✔usability test - ✔✔tests how user-friendly the interface and features are
✔✔security test - ✔✔tests vulnerability to attacks and how securely data is stored
, ✔✔load/stress test - ✔✔tests how it copes under extreme conditions
✔✔functionality test - ✔✔tests if program meets initial requirements
✔✔software development cycle - ✔✔requirements, design, implementation, testing,
maintenance
✔✔normal data - ✔✔data that user is likely to input
✔✔assemblers - ✔✔turn assembly language into machine code
✔✔AND - Conjunction - ✔✔e.g. A /\ B
✔✔OR - Disjunction - ✔✔e.g. A\/B
✔✔NOT - Negation - ✔✔e.g. -|A
✔✔ Arithmetic Logic Unit (ALU) - ✔✔Performs operations on data e.g. Addition,
subtraction
✔✔Control Unit (CU) - ✔✔Coordinating activities of the CPU
✔✔Registers - ✔✔Quick, small stores of data within the CPU
✔✔Memory Address Register (MAR) - ✔✔Holds memory address for data or a
instruction about to be used by the CPU
✔✔Memory Data Register (MDR) - ✔✔Holds actual data or instruction
✔✔Accumulator - ✔✔Stores results of calculations in the ALU
✔✔Program Counter (PC) - ✔✔Holds memory address of the instruction for each cycle
✔✔Fetch - ✔✔The next instruction is retrieved by CPU from main memory
✔✔Decode - ✔✔The instruction is broken down and decided so computer can
understand
✔✔Execute - ✔✔The CPU performs what the instructions told
✔✔Embedded System - ✔✔A computer system built within a large device e.g. Camera,
washer, car
