CBSE Class 8 Science: Important Topics for SA1 Exams

The SA1 or the CBSE Summative Assessment I is almost here now. You must be busy with your revisions and looking for final tips and suggestions for your Science exam.

No need to worry because the team of experts at Meritnation has come up with some great insights into each chapter to help you with your revisions. The key points for revision and these quick tips will be extremely helpful to you in prioritising preparations and revisions for your exam. Here are chapter wise tips and tricks for CBSE Class 8 Science:

MUST READ FOR CBSE CLASS 8 > Important Topics & Tips for: MATHS | ENGLISH

Chapter 2 – Micro organisms – Friend and Foe

This is a very interesting chapter about the world that is not visible to the naked eyes. There are many ways in which microorganisms are useful to us but they can be harmful to us as well. We need to be very careful while handling microorganisms.

Key Points to Revise in This Chapter:
1. Major groups of microorganisms
2. Uses of microorganisms
3. Harmful effects of microorganisms
4. Food poisoning
5. Nitrogen Cycle

Method for Quick Understanding:
1. To understand about microorganisms you first need to understand the different type of microbes. Then you can learn about the uses of certain microbes and harmful effects of some microbes.
2. We use various methods in our daily life either to reap benefits from microbes or to save ourselves from harmful effects of them.

MERITNATION TIP:  a) It is very important to learn about various microbes, their shape and characteristics. Conditions required for the growth of all microbes is almost same. You also must remember the name of certain microbes that are extremely useful to us like Lactobacillus is used to make curd. b) Do not miss reading about common diseases caused by microorganisms. They are very important topic.

RECOMMENDED RESOURCES: Revision Notes | Sample Papers | Textbook Solutions | Ask & Answer

Chapter 7 – Conservation of Plants and Animals

This chapter will help you become aware about the current conditions regarding environment on earth and how various factors including human activities are ruining the natural habitats of plants and organisms making their survival difficult in these conditions.

Key Points to Revise in This Chapter:
1. Deforestation
2. Conservation of forest and wild life
3. Extinct and endangered species
4. Migration
5. Recycling of paper and reforestation

Method for Quick Understanding:
To understand this chapter to its core you must understand the causes which are threatening organisms and are responsible for the extinction of certain organisms in past. Then you will be able to understand the purpose of setting up biosphere reserve, Wild life sanctuaries and National parks.

MERITNATION TIP:  Deforestation is an important topic. You must also know the difference between biosphere reserve, wildlife sanctuary and national parks and places where these are located. The definition of extinct and endangered species must be clear as you may get question regarding this. Reforestation is a remedy to conserve natural habitat for organisms hence it is also a very important topic in the view of exam.

Chapter 8 – Cell : Structure and Function

This chapter is about you and all other beings. We all are made up of cells and through this chapter we can understand about cell and its organelles.

Key Points to Revise in This Chapter:
1. Cell and cell parts
2. Structure of plant and animal cell
3. Prokaryotic and eukaryotic cells
4. System of organisation of cells

Method for Quick Understanding:
You can have a better understand about cell if you compare cell to human beings. Humans have different organs to perform various functions in body. Similarly, cells also have different organelle present in them that help the cell to perform various functions required.

MERITNATION TIP:  a) Read a little about the history of cell discovery and general characteristics of cells. b) It is very important that you remember the function of all the components of cells. It is often asked in exams. c) You must also know the difference between plant cells and animal cells with diagram.

MUST READ FOR CBSE CLASS 8 > Important Topics & Tips for: MATHS | ENGLISH

Chapter 3 – Synthetic Fibres and Plastics

Fabrics are made from fibres obtained from natural or artificial sources. This chapter is all about synthetic fibres obtained by chemical processing of petrochemicals. Synthetic fibres are Rayon, Nylon, Polyester and Acrylic. Today life without plastic cannot be imagined. But we need to use synthetic fibres and plastics in such a manner that we can enjoy their good qualities and at the same time minimise the environmental hazards for the living communities.

Key Points to Revise in This Chapter:
1. Polymer
2. Synthetic fibres and plastics
3. Types of synthetic fibres as rayon, nylon, polyester and acrylic
4. Arrangement of units in plastics as linear or cross linked
5. Thermoplastics and thermosetting plastics
6. Biodegradable and non-biodegradable materials
7. The 4 R principle: Reduce, Reuse, Recycle and Recover

Method for Quick Understanding:
1. For easy learning about rayon, nylon, polyester and acrylic, just draw a table and compare their sources, properties and uses.
It is forced to you to remember the differences between –
(i) thermoplastics and thermosetting plastics and (ii) biodegradable and non-biodegradable materials
2. With example and activity, if possible, try to explain the characteristic properties of plastics as non-reactive, light, strong, durable and poor conductors.
3. Prepare a short note about plastics as they are not environmental friendly and also how the uses of plastics can be avoided.

MERITNATION TIP: Develop a positive attitude towards exams. Prepare this chapter by learning definitions of all important terms. Try to solve a number of questions of different varieties. Also, be careful about some uncommon terms which can be asked in examination like artificial silk, PET, polycot, polywool, terylene and teflon.

Chapter 4 – Materials: Metal and Non-Metal

We are living in a world where nobody can live without the use of metals and non-matals. This a very important chapter.

Key Points to Revise in This Chapter:
1. Malleability, ductility, sonorous and lustrous with examples.
2. Conduction of heat and electricity.
3. Reactions of metals and non-metals with oxygen, water, acids and bases.
4. Displacement reactions.
5. Uses of metals and non-metals.

Method for Quick Understanding:
1. Learn that metals are hard, lustrous, malleable, ductile, sonorous and good conductors of heat and electricity but non-metals are opposite in nature.
2. Focus metals like iron, aluminium, zinc, copper, silver, calcium, magnesium, sodium, potassium, gold and mercury and non-metals like sulphur, carbon, oxygen, phosphorus for their physical and chemical properties.

MERITNATION TIP:  a) Pattern in which the questions are being asked is predefined. Students need to solve the previous years papers which will build their strong foundation to face the examination. b) Learn the names of specific metals which are least or most hard, lustrous, malleable, ductile, sonorous and good conductors of heat and electricity. c) Keep “exceptions” in mind always like all metals are solid at room temperature except mercury. d)The area you think you are weak in, study again and then attempt related questions.

RECOMMENDED RESOURCES: Revision Notes | Chapter Tests | Textbook Solutions | Ask & Answer

Chapter 11 – Force and Pressure

Picking, kicking, flicking, lifting, hitting, pushing, pulling, opening, shutting, stretching like actions involve the concept of force. Do you know that the force and area over which the force is applied are related. This relation is called pressure.

Key Points to Revise in This Chapter:
1. Forces (push and pull)
2. Contact forces (muscular and friction)
3. Non-contact forces (magnetic, electrostatic and gravitational)
4. Magnitude
5. State of motion
6. North and South poles of magnet
7. Pressure
8. Atmospheric pressure

Method for Quick Understanding:
1. Learn basic concepts like force has magnitude as well as direction and it may change the speed, direction of motion and shape.
2. Try to learn examples where effect of force is involved. You may fit various examples at each step in the following flow chart.

3. Pressure = Force/Area

MERITNATION TIP:  To capture high marks, learn many examples where effect of force is involved. Be cautious that the net effect of force is due to net force on an object. Equal and opposite forces cancel each other giving zero effect.

Chapter 12 – Friction

Do you know that an object moving over the surface of another object slows down and finally stops it? Why do we slip when we step on banana peel? This is nothing, it is friction. Even a gem cannot be polished without this friction. This chapter is all about Jekyll and Hyde of friction.

Key Points to Revise in This Chapter:
1. Force of friction
2. Factors affecting friction
3. Lubricants
4. Rolling friction
5. Sliding friction
6. Fluid friction
7. Static friction
8. Ball bearings
9. Interlocking

Method for Quick Understanding:
1. Do practice the arrangement of forces due to rolling, static and sliding frictions in a decreasing/increasing order. These friction forces can be asked by giving particular examples.
2. Methods on reducing/increasing friction.
3. Be prepared for questions on friction, whether it increases or decreases if lubricants like sand/oil/ice/powder/grease is inserted between two objects in contact.
4. You must know that fluid friction can be minimised by giving suitable shapes to bodies moving in fluids.

MERITNATION TIP:  Be sure with the fundamental concept that friction will always oppose the direction of slipping at the contacting surface. Just learn the cause of friction, its significance, how to reduce and increase, effect of friction and finally the factors on which it depends. Prepare yourself with these points, if you do, you cannot drop a good score in examination.

MUST READ FOR CBSE CLASS 8 > Important Topics & Tips for: MATHS | ENGLISH

Chapter 13 – Sound

This interesting chapter has a lot to do with practical knowledge. There are so many types of sound in the nature. Do you know why they are different? This chapter makes you aware about it.

Key Points to Revise in This Chapter:
1. Vibration
2. Amplitude
3. Frequency
4. Time period
5. Loudness
6. Pitch
7. Larynx
8. Oscillations
9. Noise
10.Noise pollution

Method for Quick Understanding:
1. Be confident with each and every term used in this chapter.
2. Learn the SI unit of frequency and time period.
3. Find out the medium through which sound can travel.
4. Relate frequency and pitch of the sound.
5. Practise numericals based on time, period and frequency.
6. Practise to draw and larynx.

MERITNATION TIP:  Questions based on numerical, conceptual, factual and logical aspects are asked from this chapter generally, hence prepare yourself accordingly.

RECOMMENDED RESOURCES: Revision Notes | Sample Papers | Textbook Solutions | Ask & Answer

Chapter 16 – Light

Light plays a very critical role in our daily life. Why are the things visible? How are there so many colours in the world? How does white sunlight give different beautiful colours? This is an amazing chapter to learn. Shadow and reflection are related with light. This chapter includes all of these.

Key Points to Revise in This Chapter:
1. Laws of reflection
2. Angle of incidence
3. Angle of reflection
4. Dispersion
5. Lateral inversion
6. Multiple images
7. Braille

Method for Quick Understanding:
1. Learn the laws of reflection by heart.
2. Practise to draw angle of incidence and angle of reflection.
3. Practice to draw image formation in a plane mirror, on an irregular surface.
4. Practice to draw and label the human eye.
5. Learn how visually challenged people read.

MERITNATION TIP:  Solve many questions based on this chapter. Be prepared to draw diagrams from this chapter which are usually asked in the exams.

All the best with your SA1 revisions and exams! 🙂

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