Annual syllabus
1. Reproduction in Animals
2. Reaching the age of adolescence
3. Force and pressure
4. Friction
5. Chemical effects of Electric current
6. Light
7. Combustion and flame
Assignment
Lesson 1 ` Crop production and management`
1.What is a crop?
2. What is ploughing and tilling ? State its advantages.
3. State the important steps taken during crop production.
4. Write short note on the terms : 1. storage and 2. harvesting
5. Propagation of ginger is generally done using
(a) Seed (b) Stem (c) root (d) leaf
6.Which activity of the farmer can promote growth of earthworms and microbes in the field ?
7. Name the tool used with a tractor for sowing seeds in a field . what are the advantages of using this tool?
8. During which months do farmers grow mustard in India?
9. What is sowing ?
10. Name the two modern methods of irrigation that help us to use water economically.
11. Why can paddy not be grown in the winter season?
Lesson 2 ` Micro- organisms : friend and foe
1.Give one word answers
(a) The process of conversion of sugar into alcohol
(b)Disease causing microbes
(c) A virus that feeds on bacteria
(d)The first scientist to have discovered microorganism
(e) The scientist who discovered vaccine for smallpopx
(f) The scientist who discovered fermentation
(g) An insect which is a carrier of parasites of malaria
(h) An insect which carries the dengue virus
(i) A biological nitrogen fixer
2. What are microorganism ? Where do they live ?
3. How microbes is used in making of curd and bread ?
4. Explain medicinal use of microorganisms.
5. Write some diseases caused by (a) Bacteria (b) virus (c) protozoa
6. What are preservatives ? Name some commonly used preservatives .
7. Explain in detail the process of pasteurisation .
8. What do you mean by carrier of disease ? Name two such carriers and the disease they caused .
9. What do you mean by food preservation ? Write some ways to preserve food.
10. Explain nitrogen cycle in detail.
Lesson 3 Coal and petroleum
Lesson 4 Combustion and flame
Q1 Fill in the blanks :
1. A blue flame on a burner shows _____ combustion .
2. Hottest part of the candle is its ____ zone .
3.Mined coal and petroleum are _____ fuels
4. ______ has the highest calorific value among the fuels.
Q2. MCQs
1. Which of the following is not used as fuels?
(a) LPG (b) CNG (c) hydrogen (d) oxygen
2. Combustion is the process of
(a) Production of explosive sound (b) Formation of carbon dioxide
(c) vaporisation of a fuel (d) burning of fuel emitting heat
3. The colour of the flame with the highest amount of fuels?
(a) white (b) yellow (c) red (d) blue
4. Which of the following is caused by burning of fuels?
(a) Acid rain (b) global warming (c) emissin of carbon monoxide (d) all of these
Q 3. Answer the following questions
1. What are the requisites of combustion ?
2. Explain different types of fuels and their uses .
3. Write a short note on the calorific value of hydrogen . How Will you differentiate an ideal fuel.(characteristics of good fuel)
4. Define the terms :- ignition temperature , calorific value of the fuel , inflammable substances
lesson 5 Conservation of plants and animals
1. Why do some birds migrate from one place to another ?
2. Name any three (a) bird santuaries (b) wildlife sanctuaries (c) national parks in India
3. list some of the natural disasters which are a danger to biodiversity
4. Why do we consider tiger an endangered species ?
5. Why each one of us must plant at least one tree in our lifetime?
6. What are the main causes of extinction of species ?
7. What purpose is served by biosphere reserves?
8. How ecosystem is the self supporting system of an organism?
9. Write a report on project tiger.
10. Define endemic species.
11. Write some ways to save paper.
Lesson 6 Reproduction in Animals
1. Short Answer questions
(a) Creation of new life of its own kind
(b)Animals which lay eggs
(c) Animals which give birth to young ones.
(d) A sperm producing organ
(e) Ova producing organs
(f) Product of fertilization
(g) The organ where fertilization takes place in humans
(h) Fusion of gametes
(i) The organ which holds foetus in females .
2. How does hydra reproduce?
3. Explain in detail the male reproductive organs.
4. Explain in detail the female reproductive organs.
5. Explain the `invitro` technique of fertilization ? Why is it necessary to adopt this method of fertilization ?
6. What is a clone? Write advantages and disadvantages of cloning.
7. Describe post fertilisation stages till the formation of foetus in women.
8. Label the parts of female and male reproductive systems:
Lesson 7 Reaching the age of adolescence
Q1 Very short answer questons
(a) Period ofgrowth from childhood to adult
(b) The first menstrual flow
(c) Stoppage of menstruation
(d) The master endocrine gland
(e) The mineral essential component of thyroxine
(f) The hormone which regulates the maturation of testes.
(g) The hormone produced by ovaries on puberty
(h) The oil secreting gland present in the skin
(i) The protruding growth of larynx in male.
(j) The spoken term used for adolescence
2. How many chances are there in nature that a woman may be a male or a female baby?
3. What is a teenage period in life? Why do we call it teenage?
4. Why doe we call the pituatary gland as master gland ?
Q2. Short Answer Questions
1. What do you mean by the terms menarche and menupause?
2. Why is a diabetic patient advised to take insulin injections?
3. What are the nutritional necessities of adolescence and why?
4. Female foeticide is a crime against humanity .
match the following:
column 1 column II
1. Growth hormones voice box
2.Pituatary gland thyroxine
3. XX chromosomes male child
4. Adrenal gland male hormone
5. THYROID gland Adrenaline
6. XY chromosomes female child
7. Pancreas stoppage of menstruation
8. testosterone insulin
9. menopause master gland
10. Adam`s apple pituitary gland
Lesson 8 Force and pressure (Grade8th)
1. It is difficult to cut cloth using a pair of scissors with blunt blades. Explain.
Ans 1 It is difficult to cut cloth using a pair of scissors with blunt blades because blunt blades have more area and due to which applied force produces very less pressure. As we know that pressure is inversely proportional to area of cross-section, so it is difficult to cut cloth from blunt blades.
2.Two women are of the same weight. One wears sandals with pointed heels while the other wears sandals with flat soles. Which one would feel more comfortable while walking on a sandy beach? Give reasons for your answer.
Answer 2. While walking on a sandy surface, one needs the footwears of larger area so that the pressure exerted on the ground is minimum. So, in this case, the woman having the sandals with pointed heels will be less comfortable in walking while the other woman wears sandals with flat soles feels more comfortable while walking on sandy beach.
3. It is much easier to burst an inflated balloon with a needle than by a finger. Explain.
Answer 3. Because needle tip has very less area of cross-section in comparison to that of our finger and we know that pressure exerted by a force is inversely proportional to the area where it has been applied, so pressure exerted will be more by the needle tip than the finger.
4.What do you mean by contact force ? Explain with the help of example.
Contact forces : Force that arises with the contact of 2 or more objects involved. Examples : Muscular force and Frictional Force
Muscular force is the type of force wherein we use our physical strength to change the state of motion of an object. Eg: Man pushing a car, Bullocks pulling a cart of load, Cycling, Weight Lifting
Frictional Force is a force that acts on all moving objects by the surface which it is in contact with.
The Frictional force is always in the direction opposite to the applied force
5..What do you mean by non contact force ? Explain with the help of example.
Non-contact forces: Forces that arise without the contact of 2 or more objects involved. Examples: Magnetic Force, Electrostatic Force, Gravitational force
Magnetic Force is a force that attracts certain metal objects (like iron and iron filings) towards a magnet.
Gravitational : it is an attractive force between two massive bodies .
G= (gmM)/r2
Electrostatic force is the force exerted by a charged body on another charged or uncharged body
6. What is meant by atmospheric pressure ? What is the cause of atmospheric pressure?
Atmospheric pressure:- The air all around us also exerts pressure. This is known as Atmospheric Pressure. The value of atmospheric pressure is very high.
Atmospheric pressure is caused by the weight of the air molecules above the Earth's surface, which are pulled downward by the planet's gravitational force.
7.Two objects repel each other. This repulsion could be due to the
(a) frictional force only (b) electrostatic force only
(c) magnetic force only (d) either a magnetic or an electrostatic force
Answer. (d) The reason for repulsions may be either an electrostatic (in case of similar charges) or a magnetic (in case of similar pole_s) force.
8.A brick is kept in three different ways on a table as shown in figure. The pressure exerted by the brick on the table will be
(a) maximum in position A (b) maximum in position C
(c) maximum in position B (d) equal in all cases
Answer. (a) Pressure will be maximum in position A because area of contact is minimum in this case and area is inversely proportional to pressure.
lesson 9 Friction
Q1. Very short answer questions :-
1.In which direction does the force of friction act on a moving object ?
2. Write the factors on which friction between the solid surfaces depends.
3.Write the factors on which the frictional force of an object while moving through a fluid depends .
4. What is the advantage of providing rollers on your travelling suitcase ?
5. What type of shoes are worn by the mountaineers and why?
6. Why do wrestlers generally apply oil on their body while going for wresting ?
Q.2. Short answer questions :-
7. List any three harmful effects of friction .
8. List some ways to reduce friction.
9. What is special about streamlined shape?
10. Give reasons for the following :-
(a) Streamline shape of the fish helps it in swimming in water
(b) Car engine gets heated on running
(c) It is always easier to roll an object than to slide it on the surface.
11. Write advantages of friction .
12. Write methods to increase friction .
Lesson 10 Sound
Lesson 11th Chemical effects of Electric current
1.Name one metal which is a good conductor of electricity.
Ans:- Graphite
2. Name some liquids which are weak conductors of electricity.
Ans:- Pure water, oil, glycerine
3. What makes tap water a conductor of electricity?
Ans:- Salts dissolved in water make the tap water good conductor of electricity.
4. Which of the two , magnetic compass or LED , is better to use in a tester and why?
Ans:-LED is better to use in a tester because it can detect even small amount of current passes . Also it is not affected by magnet nearby.
Ans 2
What is LED ? Why does the LED have one leg short and the other long?
Ans:- LED is a device which glows a very weak current and it's glow is visible even from a distance. It contains one short leg which is connected to negative terminal of battery and one leg long which is connected to positive terminal of batter in the electric circuit.
What do you understand about conductors and non Conductors of electricity?
Ans:- Conductors: the substances through which electric current passes are Called conductors. Example: silver and copper etc.
Non Conductors(Insulators) The substances through which electric current donot passes are called non Conductors (Insulators)
Ex- Wood , plastic etc
What happens when electric current is passed through a cut potato?
Ans:- When electric current is passes through cut potato, a greenish blue spot on the cut potato is formed around the positive terminal showing the change in colour on passing electric current through it.
What are the various applications of Electrolysis?
Ans:- done in class
In what way is electroplating useful?
Ans:- done in class
With the help of an activity explain electroplating of a piece of iron with copper.
Ans:- Activity to explain the electroplating of a piece of iron with copper.
Material required: iron piece , copper plate , battery , switch , wires copper sulphate solution.
Procedure. To the beaker add 50 ml water and dissolve few crystals of Copper sulphate salt .
Take a battery of suitable strength and set up the circuit through switch.
Tie the iron key to negative terminal of batter and copper plate to positive terminal of battery.
Suspend both the plates (iron and copper) in the copper sulphate solution.
Put the switch on to pass the current for 15-20 mins .
Switch off the current after some time.
Observation: the iron key is found with a shiny uniform layer of copper. It has been electroplated with copper.
What are the various uses of the chemical effects of electric current?
Ans:- Uses of chemical effects of electric current are listed below:
Electrolysis
Change in colour of metal plate
Electroplating
Purification of impure metal.
Preparing various compounds.
8. Define the following terms:-
(a)Electrolyte: a substance that produces an electrically conducting solution when dissolved in water is called electrolyte.
(b) Cathode: It is an electrode with negative charge on it. It is connected to negative terminal of battery.
© Electrolysis: It is the decomposition of a compound from its solution on passing electric current through the electrolytes of solution.
(d) anode: It is an electrode with positive charge on it . It is connected to positive terminal of battery.
(e) electroplating: process of depositing a thin film of desired metal over the object by passing current through an electrolyte in its Electrolytic solution.
(f) Galvanising: The process the depositing a layer of zinc over the other metal is called galvanising.
lesson 12 Some natural phenomena
Lesson 13 Light
1. Name the following:-
(a) A highly polished glass with a reflecting surface
(b) Irregular reflection of light
(c) Central coloured part of an eye(d) Muscles which hold the lens in the eye in position.
(e) Instrument with three mirrors which shows multiple images.
(f) Angle between incident ray and the normal.
(g) Deficiency of this nutrient causes night blindness
2. Write uses of periscope and plane mirror.
3. Write some common diseases of the human eye.
4. What makes some people colour blind?
5. How many pictures should appear per second on screen in succession to have a moving picture?
6. Write characteristics of an image formed in a plane mirror.
7. Draw diagrams showing regular and diffused reflection.
8. How will you find out how many images wil be formed when two mirrors are placed at different angles?
9. Explain the function of the following parts of human eye:-
(a) Iris (b) rods (c) Retina (d) optic nerve (e) eye lens (f) cones10. What do you mean by short sightedness and long sightedness?
11. What is cataract and what is it's treatment?
