The document is a comprehensive analysis of past CSS exam papers covering various topics in general science, including physical sciences, natural hazards, energy resources, atomic structure, and biological sciences. It includes questions about fundamental theories, phenomena, definitions, and causal explanations related to science and the environment, along with their implications. The document also addresses modern materials, disease prevention, environmental science, and pollution, providing an extensive overview of significant scientific concepts relevant to the CSS curriculum.

1. Past paper analysis
CSS GENERAL
SCIENCE by Syed
Adnan Shah
PART – I (GENERAL SCIENCE)
I. Physical Sciences
A. Constituents and Structure (Universe, Galaxy, Light Year, Solar
System, Sun, Earth, Astronomical System of Units)
What is a galaxy? The Earth belongs to which galaxy?
Briefly describe what is big bang theory.
Do you think that Pluto is still ninth planet of our solar system? If yes, how
and if not
why?
1. Describe different methods to estimate the age of the Universe.
(CSS 2018)
(c) Briefly describe the most popular and accepted theory about the origin
of the Universe.
What is ‘Black Hole’? How black holes are formed and discovered?

2. Define the term Black Hole. What’s expected inside it?
(a) List four or more physical characteristics of the Earth.
Briefly explain the difference between Sedimentary and Metamorphic
rocks.
Write short note on space shuttle.
B. Process of Nature (Solar and Lunar Eclipses, Rotation and
Revolution, Weather Variables (Global Temperature, Pressure,
Circulation, Precipitation, Humidity) and Weather Variations)
1. (A) Differentiate between the occurrence of Lunar and Solar
Eclipse? (B) Briefly explain what effects are produced due to
Rotation & Revolution of Earth? (CSS 2017)
2. Explain the formation of Lunar Eclipse. (CSS 2018)
3. What do you understand by Global Wind and Pressure patterns?
Also explain wind and pressure features at higher altitude. (CSS
2020)
Differenciate between Solar AND Lunar Eclipse
How solar eclipse and lunar eclipse are caused?
What are Kepler laws related to the motion of planets?
C. Natural Hazards and Disasters (Earth Quake, Volcanic Eruption,
Tsunami, Floods, Avalanche, Travelling Cyclone (Tropical Cyclone,
Middle Latitude Cyclone and Tornadoes), Drought, Wildfire, Urban
Fire. Disaster Risk Management)
“The flood disaster in Pakistan is caused by the follies of humans “.
Comment.
(b) Briefly explain how Seasons and Ocean Tides are produced on the
Earth?

3. Very briefly explain the difference between Earthquakes, Volcanic
eruptions, Floods and Tsunamis.
What is tsunami? How the tsunamis generated and what are their
characteristics? (b) What is an earth quake? Discuss Richter Scale
in this context. What was the intensity of the earth quake in
Pakistan dated 26 October 2015 and where was the locus? (CSS
2016)
2. Describe different causes of ‘Tsunami’. Is there any difference
between a Tsunami and a tidal wave? Name the worst Tsunami ever
recorded. (CSS 2018)
3. What is the most dangerous part of a hurricane and how do
cyclones affect humans? (CSS 2019)
4. On 7th April 2012 an Avalanche hit a Pakistan military base in
Gayari sector trapping 140 soldiers and civilians under deep snow.
What is Avalanche; describe its four types with focus on most
dangerous type? (CSS 2020)
5. World largest earthquake was assigned a magnitude of 9.5 by the
United States Geological Survey on 22 May 1960 in southern Chile
Valdivia. What do you know about earthquake? Also explain
shallow-focus and deep focus earthquakes. (CSS 2020)
6. Differentiate between Middle Latitude Cyclones and Tornadoes.
(CSS 2020)
What do you know about Volcanoes? Discuss the causes and effects of
volcanic eruptions.
What is a Tornado? How is it formed and what are the effects of tornadoes?
Explain briefly.
What is Wildfire? Explain its types, causes, spread and preventions.
Differenciate between Lava and Magma

4. Write short note on Seismography.
Explain the difference between Middle Latitude Cyclones and Tornadoes.
What are the types of earthquake waves? Discuss them
D. Energy Resources (Sources of Energy (Renewable i.e. LED Energy,
Solar Energy, Wind Energy and Non-Renewable Energy conservation
and its sustainable use)
Basically how many forms of energy are there? Also name these.
Enlist different types of energy.
Why are scientists trying to find alternate energy sources?
What is a renewable energy source? Quote three examples of renewable
energy sources.
1. Differentiate between the Renewable and Non-Renewable sources
of energy giving examples of each one of them. (CSS 2019)
2. Differentiate between the renewable and non-renewable energy
sources. Briefly explain Geothermal Energy and Hydro Electricity.
(CSS 2020)
(d) What are the advantages and limitations of renewable energy
resources? Briefly explain the prospects of non-conventional energy
resources in Pakistan.
Differentiate between renewable and non-renewable sources of energy.
Briefly explain wind energy, solar energy and biofuels.
(a) Differentiate between Renewable and Non-renewable sources of energy.
Give examples of each one of them.
(b) Why Nuclear Energy is being preferred in developed countries and why
are we lagging behind in this
important source of energy?

5. Differenciate between Renewable and Non-renewable energy resources
E. Atomic Structure, Chemical Bonding, Electromagnetic Radiations.
1. Why do atoms form bonds? Name three major types of chemical
bonds. (CSS 2019)
Write two applications of each of the following electromagnetic radiations:
(i) Ultraviolet (ii) Infra-red (iii) Microwaves (iv) Radio waves (v)
X-rays.
Briefly explain the difference between a Laser and a Photovoltaic Cell.
Write comprehensive notes on:
(a) LASER and their uses.
How heavy water differs from ordinary water and what is its use in the
Atomic Reactor?
Differentiate between
(i) Cell and battery
Briefly explain the working principle of the following: (5 each)
(a) Radar (b) Microwave Oven
Differenciate between Radiotherapy and Chemotherapy
Describe briefly the principle working of two of the followings
(i) Television (ii) Microwave oven (iii) RADAR
What is difference between the Ionic and Covalent bonding? Give examples.

6. What are longitudinal waves, electromagnetic and Gamma radiations?
Discuss them
F. Modern Materials/Chemicals (Ceramics, Plastics, Semiconductors.
Antibiotics, Vaccines, Fertilizers, Pesticides).
What is difference between Plastics and Elastics? Explain briefly.
Is plastic a natural or an artificial polymer? Describe various types of plastics
and their uses.
1. What are vaccines? Classify these and discuss DNA vaccines in
detail. (CSS 2016)
2. Why the excessive use of chemical fertilizers should be avoided?
(CSS 2019)
3. What’s the difference between vaccines and antibiotics? How do
antibiotics and vaccines contribute to health? (CSS 2019)
4. Why an indiscriminate/casual use of Antibiotics may prove
dangerous? (CSS 2019)
5. What are Pesticides? Explain their different types; why persistent
pesticides are more lethal for mankind? (CSS 2020)
“Semiconductors are the Brains of Modern Electronics”. Explain in detail
what this quotation means.
Discuss Vaccination, types of Vaccines, their side-effects and effectiveness.
Define ceramic and nano-ceramic materials. Why the nano-ceramics show
better properties than their ceramic counterparts? Write the applications of
ceramic materials.
Write short notes on the following:- (2 x 5 = 10)
(a) Nucleic acids (b) Fertilizers (c) Semiconductors (d) Microwave oven (e)
Internet

7. Very briefly explain the difference between an Insulator, a Conductor, a
Semiconductor and a Superconductor.
Briefly explain the difference between an Antibiotic, an Antiviral Drug, a
Pesticide and a Vaccine.
List any two of the three things that the MMR vaccine protects against. List
any two other vaccines given to children.
Write all that you know about Pesticides. How are they classified by
agronomists?
What part do antibodies play in allergic reactions? How vaccination can be
helpful in its control/ prevention?
Differenciat between Conductors and Insulators
Write down short note on any two of the following antibioticcs
What are fertilizers? What do you understand by NPK Fertilizers?
(a) What are pesticides? Explain how these are dangerous to human
beings?
II. Biological Sciences
Write note on: (a) Biotechnology
What is current status and future perspective of BIOTECHNOLGY in
Pakistan?
A. The Basis of Life (Cell Structures and Functions (Subcellular
Organelles such as Nucleus, Mitochondria and Ribosomes)
Decribe cell structure. Write down at least three differences between plant
and animal cell

8. Explain with examples the relationship between cells, tissues and organs.
Explain the differences in structure & function between a cell wall and a cell
membrane
What do you understand by the DNA and RNA?
How a bacterial cell is different from a plant cell?
What is the main function of: (1 x 5 = 5)
(i) Ribosome (ii) Mitochondria (iii) Lysosomes (iv) Chloroplasts
(v) Golgi apparatus
Differentiate between the following:
Deoxyribonucleic Acids (DNA)
Messenger Ribonucleic Acids (mRNA)
Proteins
(b) Explain how DNA, mRNA and Proteins are interrelated to each other.
B.Biomolecules (Proteins, Lipids, Carbohydrates and Enzymes)
1. What are carbohydrates? Classify and give detail of each class
along with examples. (CSS 2020)
Define ‘Carbohydrates’. Describe different steps to digest these in the
human body.
C. Plant and Animal Kingdom (A brief survey of plant and animal
kingdom to pinpoint similarities and diversities in nature).
What is meant by transpiration? Explain in detail the significance of leaf
structure in the process of transpiration.
(i) Why the bat and whale are considered as mammals?
What do you think cold-blooded animals are slowed down by low
temperatures?

9. Give habitats of following animals: (1 x 5 = 5)
(i) Rattle snake (ii) Ostrich (iii) Platypus (iv) Rhinoceros
(v) Chimpanzee.
(a) Porifera is an ancient group of animals from Cambrian period. What is
the cause of their survival /success?
Differenciate between Vertebrates and Invertebrates and (d) Flying
mammal and Bird
(a) In which organ these parts are present in animals or human body? (2 +
8)
(b) Describe the function of each briefly:
(i) Coronary artery (ii) Sino-auricular Node (iii) Aortic Valve (iv) Auricle
What are the Plant nutrition elements? Enumerate them
D. A Brief Account of Human Physiology
1. Comment, “liver is the chief chemist in human body”. (CSS 2016)
2. (A) Explain in detail the common causes of Heart Attack (C) Draw
the structure of human ear and briefly explain its functions (CSS
2017)
3. People suffering from cardiovascular diseases have a high level of
cholesterol in their blood. This often leads to a buildup of fats on
the internal arterial walls. Suggest how this might be harmful to
the heart. (CSS 2019)
What is meant by the term double circulation? Briefly describe how the
heart is adapted to keep blood flowing in a double circulation.
Write a note on liver juice ‘Bile’.
How the urine is formed? Describe the role of kidney in excretion

10. What is Cholesterol? Discuss its importance, normal blood level and
dangers of elevated levels with reference to the health and disease in
humans.
Briefly explain the function of following in human body: (21/2 each)
(a) Kidneys (b) Lymphatic system
(c) Thyroid gland (d) Pituitary gland
Discuss the function of kidneys in human body.
Write down short note on any two of the following harmones
Discuss the functioning of Liver and Pancreas
E. Common Diseases and Epidemics (Polio, Diarrhea, Malaria,
Hepatitis, Dengue their Causes and Prevention)
1. What are causative organism and vector for dengue, enlist possible
ways of prevention from dengue. (CSS 2016)
2. Describe different causes and preventions of ‘Polio’ (CSS 2018)
3. What do you know about Hepatitis? Describe its types and write
down preventive measures. (CSS 2020)
What is Polio? Discuss its symptoms, causes of spreading, prevention and
vaccine.
What is hepatitis, its types, causes, prevention, and cure?
Difference between Hypoglycemia and Hyperglycemia
Differenciate between Diastolic and Systolic blood pressure
Differentiate between Infection and Allergy
Differenciate between Infection and Allergy
What do you understand by Pollen Allergy.

11. What is Anemia? What are its symptoms and causes?
What do you know about hereditary diseases? Comment how they are
transferred from
parents to offsprings?
What is the Tuberculosis and Hepatitis? Explain briefly
F. New Model Concept of Producing BIO Fuel Method
1. Define the term ‘Bio-Fuel’. How is it helpful to promote clean
energy? (CSS 2018)
III. Environmental Science
A. Environment (The Atmosphere (Layered Structure and
Composition), Hydrosphere (Water Cycle, Major Water Compartments),
Biosphere (Major Biomes) and Lithosphere (Minerals and Rocks, Rock
Types, Plate Tectonics).
1. What is hydrological cycle? Discuss its importance. (CSS 2016)
2. What are the factors responsible for environmental pollution? (CSS
2017)
3. Briefly describe the various segments of atmosphere. How these
segments are maintaining the Earth Radiation Balance? (CSS
2020)
4. How the organic particulate matter enters in the atmosphere. Also
describe the sources? (CSS 2020)
What is the sequence of strata of atmosphere and on what factors does it
depends?
What is the Difference between asthenosphere and lithosphere? Explain
various components of lithosphere.

12. What is the biosphere? Write a note on the ‘Energy Resources’ available in
the biosphere.
What are the different layers of the atmosphere? On what basis these
layers are classified? In which layer ‘Auroras’ are formed and where do
satellites orbit?
Briefly explain how Photosynthesis works.
(b) Briefly explain the Nitrogen Cycle in nature.
Write short NOTES on the following: (5 each)
(a) Environmental effects of Fertilizer use. (b) Global Warming.
B. Atmospheric Pollution (Types, Sources, Causes and effects of major
air pollutants (COx, Particulate Matter, NOx, SOx, Tropospheric Ozone,
Volatile Organic Compounds, Dioxins). Regional and Global air
pollution issues (Acid- rain, Ozone Depletion, Greenhouse Effect and
Global Warming). International agreements on air pollution control
(Montreal Protocol and Kyoto Protocol).
1. What were the main objectives of Clean Development Mechanism?
Also explain the reasons for the criticism on Koyoto Protocol by the
developed countries. (CSS 2016)
2. Comment, Green House Effect is a blessing Also discuss Enhanced
Green House Effect and its relation with global warming. (CSS
2016)
3. What do you mean by Ozone depletion and how we can prevent its
depletion? (CSS 2017)
4. What is an Acid Rain and how it is produced. Briefly describe the
dangers associated with it? (CSS 2017)
5. What is ‘Acid Rain’.Describe its causes and how it can be
prevented? (CSS 2018)
6. Write a comprehensive note on ‘Smog’. (CSS 2018)
7. Why are scientists worried about the increase of Carbon Dioxide in

13. the atmosphere? (CSS 2019)
8. What does Ozone depletion mean and how can we protect the
ozone layer? (CSS 2019)
Discuss various factors which affect the variations in the climate of a place
Discuss the possible negative effects that Pakistan my face due to Global
Warming and Climate Change. What steps may be helpful to control the
climatic change?
What is the difference between fog and smog? What are the causes of
smog and its effects on human health? Write short note on any one of the
latest technologies to eliminate smog to avoid atmospheric pollution.
Write short note on Global warming
Differentiate between: (2 each)
(a) Smog and Smoke
Differenciate between
Smog and Smoke
Differenciate between Mist and Fog
Write down short note on any two of the following on the Green house
effect
(a) What is global warming? Is there a sunny side to global warming? If yes,
explain. (2 + 6)
(b) What makes the seasons happen?
C. Water Pollution (Types, sources, causes and effects of major water
pollutants (Synthetic Organic Chemicals, Oxygen Demanding Wastes,
Plant Nutrients, Thermal Pollution, Infectious Agents, Sediments,
Radioactivity, Heavy Metals and Acids). Drinking water quality and
standards.)
1. What is ‘Water Pollution’. Discuss its causes and measurement

14. methods. Name the countries with the highest and lowest
percentage of it. (CSS 2018)
2. What is natural radioactivity? How it is different from the artificial
radioactivity? (CSS 2020)
What is ‘Water Pollution’. Discuss its causes and measurement methods.
Name the countries with the highest and lowest percentage of it.
Describe water cycle and briefly explain the major processes involved in
water cycle?
Define the term Water Pollution. What indicators are used to measure the
quality of water? Write down the drinking water quality standards.
What is Radioactivity? Differentiate between natural and artificial
radioactivity
What is the role of oxygen-demanding wastes in water pollution? How it
can be prevented?
What is radioactivity? Discuss the laws of radioactivity. Name two
radioactive elements.
What are the standards of drinking water? How Heavy Metals in the water
affect the living organisms?
D. Land Pollution (Solid waste management and disposal)
1. Differentiate between Sanitary and Industrial Landfills, also
describe the land selection criteria for Landfills. (CSS 2016)
What is Solid Waste? Discuss the main issues of Solid Waste Management
in our country?
E. Role of Remote Sensing and GIS in Environmental Science.
What do you know about the Remote Sensing Techniques? Explain

15. 1.
resolution and write down the names of its various types? (CSS
2016)
What do you understand by the term Remote Sensing? Write its basic
principle. Give its important applications.
What do you know about the Remote Sensing Techniques? Explain
resolution and write down the names of its various types?
What is role of Remote sensing and GIS in environmental Science? Discuss
briefly
F. Population Planning.
What do you understand by the term Population Planning? Point out the
different benefits of Population Planning.
IV. Food Science
A. Concept of Balance Diet (Vitamins, Carbohydrates, Protein, Fats and
oil, Minerals, Fiber).
What is role of Carbohydrates and Vitamins in the body? Discuss briefly.
Explain what is meant by a balanced diet?
(b) Give the major function of the following micronutrients:
Vitamin A
Vitamin C
Iron
Calcium
Iodine
1. What is Cholesterol? Discuss its importance, normal blood level
and dangers of elevated levels with reference to the health and
disease in humans. (CSS 2016)
2. What is the significance of Vitamins? Describe the sources, uses
and deficiency symptoms of fat soluble vitamins. (CSS 2017)

16. 3. Define ‘Carbohydrates’. Describe different steps to digest these in
the human body. (CSS 2018)
4. Write a comprehensive note on ‘Balanced Diet’. (CSS 2018)
5. Deficiency of vitamins causes different human diseases some of
which are given in the table below. Choose the correct type of
vitamin from the box and write in front of each disease: Vit. A, Vit.
B1, Vit. C, Vit. D, Vit.E, Vit.K.
Disease caused due to lack of which vitamin:
1. Poor night Vision
2. Bleeding Gums
3. Rickets in Children
4. Beri-Beri
5. Anaemia
Define the term “malnutrition”. Elaborate its major causes and
consequences.
How the carbohydrates, proteins, and fats are digested in humans?
B. Quality of Food (Bioavailability of Nutrients, Appearance, Texture,
Flavor, Quality of Packed and Frozen Food, Food Additives,
Preservatives and Antioxidants)
1. Discuss importance of preservatives and antioxidants in food. (CSS
2016)
What are antioxidants and why are they used in foods? Write a short note
on natural and synthetic antioxidants.
What is difference between preservatives and antioxidants? Discuss briefly
with examples.
C. Food Deterioration and its Control (Causes of Food Deterioration,
Adulteration, Food Preservation).
1. Discuss different methods of Food preservation. (CSS 2020)
Differentiate between food contaminants and food adulterants.

17. Explain how a slice of bread after few days decomposes due to the growth
of fungi.
V. Information Technology
A. Computer (Hardware & Software Fundamentals); (I/O Processing
and data storage, Networking & Internet Standards, Application and
business Software, Social Media Websites. Information Systems.
Fundamentals of artificial intelligence)
1. Write a short note on artificial intelligence. (CSS 2016)
2. (A) Differentiate between RAM and ROM (B) Name three basic
buses employed in a computer and explain what each is used for.
(C) Draw a basic computer block diagram and briefly explain the
function of each part. (D) Describe various types of computers
classified on the basis of size, memory, capacity and speed. (CSS
2017)
4. Write a note, how data is stored on a ‘Hard Disk’. (CSS 2018)
What is ‘Artificial Intelligence’? How is it helpful for humanity?
What is a computer memory? Describe its units and discuss various types of
memories.
4.
(CSS 2018)
What 5. are the different types of a network? Explain each briefly.
(CSS 2019)
6. What is Open System Interconnections (OSI) and describe its
layers? (CSS 2020)
Explain Artificial Intelligence. What do you understand by the term
Robotics?
(ii) What is the difference among application, program and software?
What do the following abbreviations stand for:
(i) LAN (ii) HTTP (iii) HTML (iv) PDF (v) URL

18. What is difference between software and hardware? Give five examples of
each.
B. Telecommunications (Basics of Wireless Communication (Mobile,
Satellite, Surveillance and GPS and Fiber Optic etc).
1. Write short notes on: (i) Four optics (ii) Global Positioning System
(CSS 2016)
2. How an ‘Optical Fiber’ is constructed? How is it helpful in
transmitting the electromagnetic radiations? (CSS 2018)
3. Give a brief account of Optic Fibres. What is their importance in
present day telecom system? (CSS 2019)
4. Where and how Fiber Optics are used? Also write down their
advantages and disadvantages. (CSS 2020)
5. What is GPS? How does it work? (CSS 2020)
Past Papers Analysis (CSS 2015-2020)
Explain the Optical Fiber. Explain how Fiber Optic Communication works?
Differentiate between natural and artificial satellites. Briefly describe the
working of communication satellites with some applications.
Briefly explain the working and structure of a Cell Phone.
How does the Navstar GPS system work for different applications?
(i) Differentiate between network and internet.
Differentiate between natural and artificial satellites. For what purpose
artificial satellites are
used?
(b) write comprehensive note on OPTIC FIBRES and their importance in
modern telecom system.

19. Explain the mechanism of Fiber Optic Cable for signal. Explain its
construction
X.Current affairs(everday science)
(b) State the message of “The Earth Hour Movement”.
How Energy crises can be minimized in Pakistan.
IX. Out of Syllabus
1. Explain the shape of water molecule with the help of Molecular
Orbital Theory, also draw its orbital diagram. (CSS 2016)
2. What are the gamma rays? Explain their applications. (CSS 2016)
3. Briefly explain the main reasons of water-logging in Pakistan. (CSS
2017)
Differentiate between drug addiction and drug abuse. (CSS 2017)
4.
What is 5. a mirage? Describe in detail the creation of mirage. (CSS
2017)
6. Most of the household appliances utilize ‘DC’ then why we
generate ‘AC’ at power stations? (CSS 2017)
7. Explain the terms Dark Energy and Dark Matter. (CSS 2018)
8. Define the term Black Hole. What’s expected inside it? (CSS 2018)
9. Give a brief account of Biotechnology. (CSS 2019)
10. Do the mammals also lay eggs? If yes, where in the world do they
live? Write the name of some of them. (CSS 2019)
11. How can the Sun have such a strong gravitational field if it’s made
of gases? (CSS 2019)

20. 12. What are the Fossils? Discuss the importance of paleontology.
(CSS 2020)
Differentiate between any FIVE of the following pairs:- (5 x 2 = 10)
(a) Typhoons and Tornadoes (b) Microscope and Telescope (c) Ultrasonics
and Infrasonics
(d) Hard water and Heavy water (e) Isotopes and Isomers (f) Antibodies and
Antibiotics
(g) Antigen and Vaccine
(a) What is Nanotechnology and what are its uses?
(b) Briefly explain the differences between Chemotherapy and
Radiotherapy.
(b) What do the following scientific abbreviations stand far? (1/2 each)
(i) STP (ii) LORAN (iii) SONAR (iv) MAF
(v) MeV (vi) MASER
Xi..CONCEPTUAL QUESTIONS
Give brief explanations for following phenomena: (2 each)
(a) While watching a cricket match we see the ball struck a moment before
we
hear the sound of the bat hitting the ball.
(b) A ship though made largely of steel, which is heavier than water, floats
in
water.
(c) The colour of the same cloth when seen in electric light appears
different from
the colour when seen in day light.
(d) Glass when heated cracks while metal does not.
(e) Although each eye perceives a separate image, we do not see everything
double.

21. Give brief answers to the following questions: (2 each)
(a) Why do we bring our hands close to our mouth while shouting across to
someone far away?
(b) Why do we lean forward while climbing a hill?
(c) Why does a swimming pool appear less deep than it actually is?
(d) Why cannot petrol fire be extinguished by water?
(e) Why do Australians celebrate their Christmas during summer?
What do mean by night vision technology?