General Science 7th Class Chapter 3 Immunity and Diseases Solved Exercise

General Science

7th Class

Chapter 3

Immunity and Diseases

Questions

3.1 Encircle the correct option.

1. A pigment in the skin that protects harmful effects of sunlight:

a. melanin        b. haemoglobin        c. lymphocyte        d. lysozyme

2. Hydrochloric acid is found in:

a. saliva        b. gastric juice        c. bile        d. pancreatic juice

3. ________ is the inflammation of liver.

a. tuberculosis        b. typhoid        c. COVID-19        d. hepatitis

4. Billions of new blood cells are produced daily in:

a. heart        b. lever        c. spleen        d. bone-marrow

5. Nuclear membrane is not found in:

a. plant cell        b. animal cell        c. bacterial cell        d. fungal cell

3.2 Give short answers.

i. Define the following:

(a) Pathogen

(b) Antigen

(c) Infection

(d) Phagocytosis

Ans.

(a) Pathogen

Microorganisms that cause diseases in human body are called pathogen.

(b) Antigen

An antigen is a toxin or other foreign substances which induces an immune response in the body, the production of antibodies.

(c) Infection

Entry and growth of microorganisms into our body called infection.

(d) Phagocytosis

Phagocytosis is a cellular process of ingesting and eliminating foreign substances and microorganisms.

General Science 7th Class Chapter 2 Human Respiratory and Circulatory Systems Solved Exercise

General Science

7th Class

Chapter 2

Human Respiratory and Circulatory Systems

Questions

2.1 Encircle the correct option.

1. Exchange of gases takes place in:

a. lungs        b. bronchioles        c. alveoli        d. blood

2. Trachea divides into two:

a. bronchi        b. veins        c. villi        d. ribs

3. The part of the heart which receives blood from lungs:

a. left atrium        b. right atrium        c. left ventricle        d. right ventricle

4. Left atrium opens into:

a. Right atrium        b. right ventricle        c. left ventricle        d. aorta

5. Right atrium receives:

a. oxygenated blood        b. deoxygenated blood        c. both types of blood        d. no blood

6. Blood vessels that carry blood away from the heart are:

a. capillaries        b. veins        c. arteries        d. venules

7. Aerobic respiration takes place in:

a. mitochondria        b. chloroplasts        c. nucleus        d. blood vessels

8. Products of anaerobic respiration in yeasts are _________ along with energy:

a. carbon dioxide and water        b. ethanol and carbon dioxide

c. oxygen and water        d. lactic acid and water

9. Exchange of material in the body tissues and blood takes place in:

a. aorta        b. ventricles        c. veins        d. capillaries

10. Which of the following plays an important role in blood clotting?

a. red blood cells        b. white blood cells        c. platelets        d. bone cells

2.2 Differentiate between:

1. Aerobic and anaerobic respiration

Ans:

Aerobic Respiration:

• It takes place in the presence of oxygen
• Large amount of energy is released in aerobic respiration
• Carbon dioxide and water are the products of aerobic respiration

Anaerobic Respiration:

• It takes place in the absence of oxygen
• Small amount of energy is released in anaerobic respiration
• Lactic acid is produced in muscle. Ethanol and carbon dioxide are produced in yeast

2. Oxygen and carbon dioxide

Ans:

Oxygen:

     In animals, oxygen is very important for the process of aerobic respiration. In result,             large amount of energy is released in organism's body. Organisms inhale oxygen from         environment.

Carbon dioxide:

     Carbon dioxide is the by product of respiration and it is exhaled from lungs by animals         and in plants by stomata.

3. Breathing and respiration

Ans:

Breathing:

• Breathing is the exchange of gases by inhalation and exhalation of the air.
• It takes place in alveoli of the lungs.
• The purpose of breathing is to provide oxygen to all the body cells and getting rid of carbon dioxide produced in the cells.

Respiration:

• Respiration is a process to release energy from food during a series of reaction, each of which is catalyzed by specific enzymes.
• It takes place in mitochondria of the cells.
• The purpose of respiration is to provide energy to the whole body for carrying on the activities of life.

4. Arteries and Veins

Ans:

Arteries:

• Carry blood away from the heart
• Thick walled vessels
• Facing high blood pressure
• having no valves
• Carry blood having oxygen and nutrients for the body cells, except pulmonary artery which carries deoxygenated blood.

Veins:

• Carry blood towards the heart
• Thin walled vessels
• Facing low blood pressure
• Veins have valves
• Return blood carrying carbon dioxide and other wastes, except pulmonary vein which carries oxygenated blood.

5. Capillaries and alveoli

Ans:

Capillaries:

    Capillaries provide surface area for exchange of materials between the body cells and blood cells.        They provide oxygen and nutrients to the cells and collect carbon dioxide and other wastes from the     cells.

Alveoli:

    In lungs, each bronchiole ends in a group of air sacs or alveoli. The lungs look like sponges due to        the presence of alveoli. Millions of alveoli are found in the lungs. They are surrounded by thick            network of blood capillaries.

2.3 Give short answers.

i. Name the body parts involved in breathing system.

Ans.

1. Nose or Mouth

2. Trachea

3. Bronchus

4. Bronchiole

5. Alveolus in lung

6. Blood Capillaries

ii. Name the products of anaerobic respiration which occurs in muscles.

Ans.

Lactic acid is the product of anaerobic respiration which occurs in muscle.

iii. Name different blood cells.

Ans.

(i) Red blood cells (RBCs)

(ii) White blood cells (WBCs)

(iii) Platelets

iv. Where does blood oxygenate?

Ans.

Blood is oxygenated by alveoli in the lungs.

v. Name different chambers of human heart.

Ans.

Human Heart has following chambers:

1. Right atria

2. Left atria

3. Right ventricle

4. Left ventricle

General Science 7th Class Chapter 1 Plant Systems Solved Exercise

General Science

7th Class

Chapter 1

Plant Systems

Questions

1.1 Encircle the correct option.

(i) Water and dissolved salts are conducted from roots to leaves by:

a. root hairs        b. xylem        c. phloem        d. stomata

(ii) The innermost layer of cortex in the root:

a. epidermis        b. endodermis        c. pericycle        d. cambium

(iii) What is required for photosynthesis in addition to light?

a. oxygen and carbon dioxide            b. oxygen and water

c. carbon dioxide and water            d. nitrogen and water

(iv) Oxygen and ________ are the products of photosynthesis:

a. water        b. carbon dioxide        c. glucose        d. chlorophyll

(v) The products of respiration are carbon dioxide and:

a. water        b. oxygen        c. mitochondria        d. chloroplast

(vi) The loss of water from aerial parts of the plants:

a. respiration        b. photosynthesis        c. evaporation        d. transpiration

(vii) Chlorophyll is present in:

a. mesophyll cells        b. upper epidermis        c. lower epidermis        d. endodermis

(viii) Mineral required in the formation of chlorophyll:

a. iodine        b. iron        c. phosphorus        d. magnesium

(ix) The force between the molecules of water:

a. adhesive force        b. cohesive force        c. repulsive force        d. magnetic force

(x) Rate of transpiration decreases with the increase of:

a. temperature        b. light intensity        c. humidity in air        d. wind speed

1.2. Write short answers.

i. What is primary root?

Ans.

The initial root which grows from radicle of the embryo is the primary root or also called as tap root.

ii. What is secondary root?

Ans.

The branches of primary roots are called secondary roots.

iii. State the function of root cap.

Ans.

Root cap protects the newly born soft cells from being damaged and environmental stresses. It enables root tip to grow through soil.

iv. Write word equation for photosynthesis.

Ans.

Carbon dioxide + Water + Sunlight energy → Food (Glucose) + Oxygen

v. Write word equation for respiration.

Ans.

Food (Glucose) + Oxygen → Carbon dioxide + Water + Chemical energy

Computer 201-250 MCQs

Computer

201. _________ is the most important/powerful computer in a typical network?

a. Desktop

b. Network client

c. Network server

d. Network station

202. The software that is used to create text-based documents are referred to as ________ ?

a. DBMS

b. Suites

c. Spreadsheets

d. Word processors

203. _________ devices convert human understandable data and programs into a form that the computer can process?

a. Printing

b. Output

c. Solid state

d. Input

204. What features adjusts the top and bottom margins so that the text is centered vertically on the printed page?

a. Vertical justifying

b. Vertical adjusting

c. Dual adjusting

d. Horizontal centering

205. Which of these is not a means of personal communication on the internet?

a. Chat

b. Instant messaging

c. Insta notes

d. Electronic mail

206. What is the overall term for creating editing, formatting, storing, retrieving and printing a text document?

a. Word processing

b. Spreadsheet design

c. Web design

d. Database management

207. Fourth generation mobile technology provides enhanced capabilities allowing the transfer of both ________ data, including full-motion video, high-speed internet access, and video conferencing.

a. video data and information

b. voice and non-voice

c. music and video

d. video and audio

208. Which of these is a point and draw device?

a. Mouse

b. Scanner

c. Printer

d. CD-ROM

209. A set of rules for telling the computer what operations to perform is called a _________ ?

a. procedural language

b. structures

c. natural language

d. programming language

210. A detailed written description of the programming cycle and the program, along with the test results and a printout of the program is called ________ ?

a. documentation

b. output

c. reporting

d. spec sheets

211. Forms that are used to organize business data into rows and columns are called _________ ?

a. transaction sheets

b. registers

c. business forms

d. spread sheets

212. In power point, the header and footer button can be found on the insert tab in what group?

a. Illustrations group

b. Object group

c. Text group

d. Tables group

213. A(n) _________ is a set of programs designed to manage the resources of a computer, including starting the computer, managing programs, managing memory and coordinating tasks between input and output devices?

a. application suite

b. compiler

c. input/output system

d. operating system

214. A(n) ________ program is one that is ready to run and does not need to be altered in any way.

a. Interpreter

b. High level

c. Compiler

d. Executable

215. What is the name given to those applications that combine text, sound, graphics, motion video, and/or animation?

a. Motionware

b. Anigraphics

c. Videoscapes

d. Multimedia

216. A(n) _________ language reflects the way people think mathematically.

a. cross-platform programming

b. 3GL business programming

c. event driven programming

d. functional

217. When entering text within a document, the Enter key is normally pressed at the end of every ________ ?

a. Line

b. Sentence

c. Paragraph

d. Word

218. Which of the following software could assist someone who cannot use their hands for computer input?

a. Video conferencing

b. Speech recognition

c. Audio digitizer

d. Synthesizer

219. Memory unit is one part of _________ ?

a. Input device

b. Control unit

c. Output device

d. Central Processing Unit

220. Microprocessors can be used to make _________ ?

a. Computer

b. Digital systems

c. Calculators

d. All of the above

221. Which statement is valid about computer program?

a. High level languages must be converted into machine language to execute

b. High level language programs are more efficient and faster to execute

c. It is more difficult to identify errors in high level language program that in low level programs

d. All of above

222. By programmable machine we mean ________ ?

a. computers

b. modern television

c. washing machines

d. anything that can be set to perform different tasks with suitable programs

223. Which of the following is a secondary memory device?

a. Keyboard

b. Disk

c. ALU

d. All of the above

224. One of the popular mass storage device is CD ROM. What does CD ROM stand for?

a. Compactable Read Only Memory

b. Compact Data Read Only Memory

c. Compactable Disk Read Only Memory

d. Compact Disk Read Only Memory

225. Identify the true statement about computer.

a. Computers are 100% accurate but it can suffer from GIGO (Garbage In Garbage Out)

b. Computers are reliable because they use electronic component which have very low failure rate

c. Computer is never tired and does not suffer from boredom

d. All of above

226. The programs which are as permanent as hardware and stored in ROM is known as ________ ?

a. Hardware

b. Software

c. Firmware

d. ROM ware

227. Which of the following memories must be refreshed many times per second?

a. Static RAM

b. Dynamic RAM

c. EPROM

d. ROM

228. What do you call the translator which takes assembly language program as input & produce machine language code as output?

a. Compiler

b. Interpreter

c. Debugger

d. Assembler

229. Serial access memories are useful in applications where:

a. Data consists of numbers

b. Short access time is required

c. Each stored word is processed differently

d. Data naturally needs to flow in and out in serial form

230. In ________ mode, the communication channel is used in both directions at the same time?

a. Full-duplex

b. Simplex

c. Half-duplex

d. None of the above

231. Who invented Slide Rules?

a. John Napier

b. William Oughtred

c. Gottfried Leibnitz

d. Blaise Pascal

232. The proper definition of a modern digital computer is ________ ?

a. An electronic automated machine that can solve problems involving words and numbers

b. A more sophistic and modified electronic pocket calculator

c. Any machine that can perform mathematical operations

d. A machine that works on binary code

233. Which of the printers used in conjunction with computers uses dry ink powder?

a. Daisy wheel printer

b. Line printer

c. Laser printer

d. Thermal printer

234. In which generation Computers vacuum tube were used?

a. First generation

b. Second generation

c. Third generation

d. Fourth generation

235. IC are classified on the basis of _________ ?

a. Manufacturing company

b. Type of computer

c. Number of transistors

d. None of these

236. Process of loading and fixing or bypassing errors in computer program code is called ________ ?

a. Debugging

b. Defusing

c. Defragmenting

d. Defrosting

237. CSS stands for ________ ?

a. Central Superior Services

b. Cascading style sheets

c. Both

d. None of above

238. TCP/IP invented by ________ ?

a. Robert E. Kahn

b. Vint Cerf

c. Alan turing

d. A & B

239. Smallest font size in MS-word is ________ ?

a. 6

b. 8

c. 10

d. 12

240. The World Wide Web was invented by ________ ?

a. Tim Berners-Lee

b. Bob Kahn

c. Steve Jobs

d. Bill Gates

241. Wifi Stands For ________ ?

a. Wireless Fidelity

b. Wireless functioning

c. Wireless function

d. None of the above

242. Which of the following is true regarding page Orientation of a Document?

a. Page Orientation can be changed at any time

b. Page Orientation of document determines by printer

c. Page Orientation must be set before start typing

d. Page Orientation of a document cannot be changed

243. Vector graphics is composed of ________ ?

a. Pixels

b. Paths

c. Palette

d. None of above

244. Shortcut key for Change case is _______ ?

a. Shift+F3

b. Ctrl+Shift+F3

c. Ctrl+F5

d. Ctrl+Alt

245. Rearranging data in a new sequence is known as ________ ?

a. Uploading

b. Updating

c. Sorting

d. Summarizing

246. Which device is used to process data?

a. CPU

b. RAM

c. DCU

d. VDU

247. Pressing F8 for three time selects ________ ?

a. A sentence

b. A paragraph

c. A word

d. Entire document

248. Which of the following types of memory improves processing by acting as a temporary high speed holding area between the memory and the CPU?

a. RAM

b. ROM

c. EPROM

d. Cache memory

e. Flash memory

249. Windows 10 was launched in which year?

a. 2012

b. 2013

c. 2015

d. 2014

250. Which one is not a nickname of a version of Android?

a. Honeycomb

b. Cupcake

c. Gingerbread

d. Muffin

Computer 151-200 MCQs

Computer

151. Which of the following contains permanent data and gets updated during the processing of transactions?

a. Operating System File

b. Transaction File

c. Software File

d. Master File

152. A modem is connected to ________ ?

a. a telephone line

b. a keyboard

c. a printer

d. a monitor

153. Large transaction processing systems in automated organizations use ________ ?

a. Online processing

b. Batch processing

c. Once-a-day processing

d. End-of-day processing

154. Which of the following is not a storage medium?

a. Hard disk

b. Flash drive

c. DVD

d. Scanner

155. The computer abbreviation KB usually means _______ ?

a. Key Block

b. Kernel Boot

c. Kilo Byte

d. Kit Bit

156. The typical computer criminal is a(n) ________ ?

a. Young hacker

b. Trusted employee with no criminal record

c. Trusted employee with a long, but unknown criminal record

d. Overseas young cracker

157. The common name for the crime of stealing passwords is ________ ?

a. Jacking

b. Identify theft

c. Spoofing

d. Hacking

158. Collecting personal information and effectively posing as another individual is known as the crime of ________ ?

a. Spooling

b. Identity theft

c. Spoofing

d. Hacking

159. Malicious software is known as ________ ?

a. Badware

b. Malware

c. Maliciousware

d. Illegalware

160. A program that performs a usual task while simultaneously allowing destructive acts is a ________ ?

a. Worm

b. Trojan horse

c. Virus

d. Macro virus

161. An intentionally disruptive program that spreads from program to program or from disk to disk is known as a ________ ?

a. Trojan horse

b. Virus

c. Time bomb

d. Time-related bomb sequence

162. In 1999, the Melissa virus was a widely publicized: ________ ?

a. E-mail virus

b. Macro virus

c. Trojan horse

d. Time bomb

163. What type of virus uses computer hosts to reproduce itself?

a. Time bomb

b. Worm

c. Melissa virus

d. Macro virus

164. The thing that eventually terminates a worm virus is a lack of:

a. Memory or disk space

b. Time

c. CD drives space

d. CD-RW

165. When a logic bomb is activated by a time-related event, it is known as a ________ ?

a. Time-related bomb sequence

b. Virus

c. Time bomb

d. Trojan horse

166. What is the name of an application program that gathers user information and sends it to someone through the internet?

a. Virus

b. Spybot

c. Logic bomb

d. Security patch

167. ________ is the measurement of things such as fingerprints and retinal scans used for security access?

a. Biometrics

b. Bio measurement

c. Computer security

d. Smart weapon machinery

168. What is the most common tool used to restrict access to a computer system?

a. User logins

b. Passwords

c. Computer keys

d. Access-control software

169. Hardware or software designed to guard against unauthorized access to a computer network is known as a(n) ________ ?

a. Hacker-proof program

b. Firewall

c. Hacker-resistant server

d. Encryption safe wall

170. The scrambling of code is known as ________ ?

a. Encryption

b. a firewall

c. Scrambling

d. Password proofing

171. To prevent the loss of data during power failures, use a(n) _________ ?

a. Encryption program

b. Surge protector

c. Firewall

d. UPS

172. ________ is defined as any crime completed through the use of computer technology?

a. Computer forensics

b. Computer crime

c. Hacking

d. Cracking

173. ________ refers to electronic trespassing or criminal hacking?

a. Cracking

b. Jacking

c. Spoofing

d. Smarming

174. The first electronic computer was developed by ________ ?

a. J.V. Attansoff

b. Bill Gates

c. Simur Cray

d. Winton Serf

175. ________ computers operates essentially by counting?

a. Portable computer

b. Hybrid computer

c. Analog computer

d. Digital computer

176. ________ computer is small general purpose micro computer, but larger than portable computer?

a. Hybrid

b. Digital

c. Desktop

d. Laptop

177. Cathode Ray Tube is a form of ________ ?

a. Keyboard

b. Mouse

c. Monitor

d. Mother board

178. ________ computer is a medium sized computer?

a. Micro

b. Mainframe

c. Super

d. Mini

179. ________ computer are of large size?

a. Micro

b. Mainframe

c. Super

d. Mini

180. Note book, laptop, palm, hand-held computers are coming under the category of ________ computer?

a. Digital computer

b. Mainframe computer

c. Portable computer

d. Hybrid computer

181. Touch Screen is ________ ?

a. Input device

b. Output device

c. Both A & B above

d. None of these

182. ________ are used for plotting graphs and design on papers?

a. Trackball

b. Joystick

c. Light pen

d. Plotters

183. ________ are specific to users' needs?

a. System software

b. Application software

c. Assemblers

d. Compilers

184. "MAN" stands for ________ ?

a. Maximum Area Network

b. Minimum Area Network

c. Main Area Network

d. Metropolitan Area Network

185. Which of the following is a network topology?

a. LAN

b. WAN

c. MAN

d. BUS

186. VOIP stands for ________ ?

a. Voice Over IP

b. Video Over IP

c. Viruses Over IP

d. Virtual Over IP

187. LAN stands for ________ ?

a. Limited Area Network

b. Logical Area Network

c. Local Area Network

d. Large Area Network

188. ________ are set of rules and procedures to control the data transmission over the internet?

a. IP address

b. Domains

c. Protocol

d. Gateway

189. NOS stands for ________ ?

a. Node Operating System

b. Non-open software

c. Network Operating System

d. Non-operating software

190. ________ are system software to facilitate editing of text and data?

a. MS Word

b. Editors

c. Power Point

d. MS publisher

191. Computers, combine both measuring and counting, are called ________ ?

a. Analog

b. Digital

c. Hybrid

d. All of these

192. In world today, most of the computers are ________ ?

a. Digital

b. Hybrid

c. Analog

d. Complex

193. Physical structure of computer is called ________ ?

a. Software

b. Hardware

c. Human ware

c. All of these

194. In which type of computer, data are represented as discrete signals?

a. Analog Computer

b. Digital Computer

c. Both

d. Hybrid Computer

195. C' in CPU denotes ________ ?

a. Central

b. Common

c. Convenient

d. Computer

196. Which of the following uses a handheld operating system?

a. Supercomputer

b. Personal computer

c. Laptop

d. PDA

197. To display the contents of a folder in Windows Explorer you should:

a. Click on it

b. Collapse it

c. Name it 

d. Give it a password

198. The CPU comprises of Control, Memory and ________ units?

a. Microprocessor

b. Arithmetic/Logic

c. Output

d. ROM

199. A(n) _________ appearing on a web page opens another document when clicked.

a. anchor

b. URL

c. hyperlink

d. reference

200. ________ is a windows utility program that locates and eliminates unnecessary fragments and rearranges files and unused disk space to optimize operations?

a. Backup

b. Disk cleanup

c. Disk Defragmenter

d. Restore