Computer-Science-A-level-Ocr
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3-3-networks8 主题
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3-2-databases7 主题
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3-1-compression-encryption-and-hashing4 主题
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2-5-object-oriented-languages7 主题
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2-4-types-of-programming-language4 主题
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2-3-software-development5 主题
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2-2-applications-generation6 主题
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2-1-systems-software8 主题
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1-3-input-output-and-storage2 主题
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1-2-types-of-processor3 主题
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1-1-structure-and-function-of-the-processor1 主题
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structuring-your-responses3 主题
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the-exam-papers2 主题
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8-2-algorithms-for-the-main-data-structures4 主题
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8-1-algorithms10 主题
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7-2-computational-methods11 主题
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7-1-programming-techniques14 主题
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capturing-selecting-managing-and-exchanging-data
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entity-relationship-diagrams
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data-normalisation
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relational-databases
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hashing
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symmetric-vs-asymmetric-encryption
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run-length-encoding-and-dictionary-coding
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lossy-and-lossless-compression
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polymorphism-oop
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encapsulation-oop
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inheritance-oop
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attributes-oop
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methods-oop
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objects-oop
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capturing-selecting-managing-and-exchanging-data
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6-5-thinking-concurrently2 主题
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6-4-thinking-logically2 主题
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6-3-thinking-procedurally3 主题
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6-2-thinking-ahead1 主题
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6-1-thinking-abstractly3 主题
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5-2-moral-and-ethical-issues9 主题
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5-1-computing-related-legislation4 主题
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4-3-boolean-algebra5 主题
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4-2-data-structures10 主题
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4-1-data-types9 主题
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3-4-web-technologies16 主题
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environmental-effects
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automated-decision-making
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computers-in-the-workforce
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layout-colour-paradigms-and-character-sets
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piracy-and-offensive-communications
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analysing-personal-information
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monitoring-behaviour
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censorship-and-the-internet
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artificial-intelligence
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the-regulation-of-investigatory-powers-act-2000
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the-copyright-design-and-patents-act-1988
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the-computer-misuse-act-1990
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the-data-protection-act-1998
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adder-circuits
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flip-flop-circuits
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simplifying-boolean-algebra
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environmental-effects
BIOS
What does BIOS mean?
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In A Level Computer Science, BIOS refers to the Basic Input/Output System of a computer
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BIOS is a piece of firmware stored on a small memory chip on the motherboard
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On system start, the BIOS is the first software to run
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It performs a POST (Power-On Self-Test), a diagnostic testing sequence that ensures all the hardware components are working properly
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If the BIOS encounters any errors during this test, it will either halt the boot process or issue an error message
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If the POST succeeds, the BIOS will run the Bootstrap loading sequence, which is the program responsible for starting the operating system
Worked Example
In the late 1990s, the CIH virus hit the headlines because it could overwrite and destroy the contents of a computer’s BIOS.
Describe the effect of a computer having its BIOS overwritten.
[2]
How to answer this question:
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Explain the role of BIOS in a computer system
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Explain the consequence of having a destroyed BIOS
Answer:
Example answer that gets full marks:
The BIOS is crucial in initialising the hardware components and operating the system. If a virus, such as the CIH virus, overwrites or destroys the contents of a computer’s BIOS, it will be unable to perform the Power-On Self-Test (POST) and fail to load the bootstrap program. This would mean the computer will not be able to initialise the operating system.
Acceptable answers you could have given instead:
If the BIOS has been overwritten, it will not be able to perform the Power-On Self-Test (POST) and, therefore, unable to load the bootstrap program. This would mean the operating system would fail to start.
Responses