CBSE Class 7 Computer Science Assignment Set A

CLASS - VII
SUBJECT- COMPUTER
TOPIC- COMPUTER VIRUS AND DETECTION

FILL IN THE BLANKS :

Question. A virus can corrupt ______  on a computer system.

Answer : files

Question. Worms are viruses that copy themselves and spread everywhere to affect the ______  of a computer system.

Answer : speed

Question. Computer virus does not damage the ______  and ______ .

Answer : keyboard,monitor 

Question. ______  is an antivirus software program.

Answer : AVG

Question. ______ is a software used to detect and delete viruses present on a computer system.

Answer : Antivirus

Question. A virus can attack a computer system by entering through an ______.

Answer : E-mail

Question. ______ is a program usually designed to irritate operators or harm a computer sytem.

Answer : Virus

Question. ______  is a type of computer virus.

Answer : Bomb 

Question. A computer virus program may ______ itself to the hard disk and system files.

Answer : copy

Question. ______  are viruses that may appear in form of infected videos, games etc.

Answer : Trojans

SHORT ANSWER QUESTIONS :

Question. What are the routes of virus attacks ?
Answer : Some of the routes from which a virus can attack a computer system are-
(i) E-mail
(ii) Infected pendrive and CD’s.
(iii) Download infected files.
(iv) Starting an infected application.

Question. Write a note on harms of a computer virus ,
Answer : Harms caused by computer viruses Most of the virus programs are applied to confuse and irritate the operators. But other viruses can prove to be very harmful to a computer system. They can modify or corrupt files, delete data, steal pass words etc.

Question. What is Computer Virus . Enlist all types of computer viruses .
Answer : A Computer virus is a destructive software program that is usually made to corrupt or delete data on a computer by erasing information available on the hard disk . It can spread from one computer to another by use of disks , networks , e -mail etc.
Types of Computer Virus 
(i) BOMBS
(ii) BOOT SECTOR VIRUSES
(iii) E-MAIL VIRUSES
(iv) TROJANS
(v) WORMS

Question. What are E-mail viruses ?
Answer : E-mail viruses enter the computer system when an infected e-mail or its attachments is opened.

Question. What are the protection measures seeked to prevent a virus from entering into a Computer System ?
Answer : These are some of the protection measures seeked to prevent a virus from entering into a computer system 
(i) Do not use an infected CD or pendrive.
(ii) Do not open or download files from malicious websites.
(iii) Use security passwords to limit outsider’s access to a computer system.
(iv) Get an antivirus program installed.

Question. What is an Antivirus ? Name some antivirus software programs.
Answer : Antivirus programs are used to detect and remove viruses . we can install any of these antivirus programs readily available in the market.
(i) NORTON
(ii) AVG
(iii) F-SECURE
(iv) KASPERSKY

Question. How does a boot secter virus affect the working of a computer ?
Answer : Boot secter viruses are very destructive as they damage the boot sector part of a hard disk or floppy disk where data is stored.