• CLASS-7 • COMPUTER • CH-3 • COMPUTER VIRUS • ANSWER KEY OF BOOK WORK AND COPY WORK • Fill in the blanks: (pg-36) 1. A computer virus disrupts the normal operation of a computer. 2. Computer virus results in loss of speed and distruction of data. 3. Stone virus is a type of boot Virus. 4. Creeper virus was first detected on ARPANET. 5. MyDoom is the most expensive virus in the world. 6. Antivirus software are designed to identify, prevent and remove virus from a computer. • State True or False (pg-37) 1. A computer virus is similar to biological virus. False(Not similar) 2. All virus programs cause harm to data or programs. False(Some) 3. Trojan Horses are self replicated. False (Not self replicated) 4. A worm is similar to a virus in design. True 5. Spyware creates a backdoor on a computer. F(TROJAN HORSE) 6. We should not equip our computer with anti virus programs. False
• Application Based Questions (pg-37) 1. Varsha’s computer has got infected with a virus which lead to the frequent hanging of the system. Which software will you suggest her to install in order to solve this problem? Ans- Anti-virus software. 2. Sumit’s computer is not working properly . The executable files and programs with extensions , like ,.com ,.exe,.ovl,.sys, on his PC have got infected . What type of virus has entered into his computer? Ans- Program File viruses. • Multiple Choice Question (pg-37) • Which virus infects the boot record or master boot records?
a)Worm b) Boot virus c) Spyware
• Which virus is named after the wooden horse used by the Greek Army to conquer the city of Troy?
a)Dark Avenger b)Stoned Virus c)Trojan Horse • When was the first PC virus released?
a) 1897 b) 1985 c) 1987
• Which one of the following is the name of a virus?
a) Jan First b) May First c) April First
• Who released the first PC virus ?
a) Duke Brothers b) Wright Brothers
c) Farooq Alvi Brothers
• Answer the following: (pg-37-38) Q-1. What is a Computer virus? Name its types. Ans- A computer virus is a program or a set of programs that disrupts the normal operation of computer. There are four types of viruses: 1. Boot Viruses 2. Program File Viruses 3. Multipartite virus 4. Macro virus Q-2. Write any three possible symptoms of virus in a computer. Ans- 1. Speed of computer drops. 2. Computer may shut down and restart frequently. 3. Computer start doing things on its own. Q-3. What do you understand by the term Spyware? Ans- Spyware is a type of malicious software that gains entry into a system without the knowledge of user. Q-4. Explain the working of Trojan Horses. Ans- Trojan Horse are simple programs that pretend to be useful applications but they always do something destructive: 1. By adding silly desktop icons. 2. By creating a backdoor on a computer that gives an easy access to malicious software
Q-5. Write any three steps required to protect your computer virus attack. Ans- Equip the PC with some anti-virus program. • Always scan the pen drive before copying files. • Do not install pirated software. Q-6. Briefly explain antivirus software. Name the antivirus software which is being used in your school computers. Ans- Antivirus is used to identify, prevent and remove virus from our computer. The antivirus software which we use in our school computers is:- • AVG Antivirus
• Copy work
Defines Terms 1. Malware is a malicious software that enter Malware into a computer and damages it without the user’s knowledge. 2. Boot sector virus infects the boot sector of Boot sector the hard drive. virus 3. Program file virus infects the executable Program file files or programs. virus 4. Multipartite virus is a hybrid of a boot Multipartite sector virus and program file virus virus Full forms 1. Vital Information Resources Under Seize VIRUS