Showing posts with label class7-science. Show all posts
Showing posts with label class7-science. Show all posts

Thursday 20 December 2012

CBSE Class 7 - Science - CH8 - Winds, Storms and Cyclones

Winds, Storms and Cyclones
CBSE Class 7 - Science - CH8 - Winds, Storms and Cyclones
Cyclone Hit at Samoa Islands
credits: NOAA

NCERT Solutions, Q & A

Q1: Fill the missing word in the blank spaces in the following statements:

(a) Wind is _________ air.
(b) Winds are generated due to ________ heating on the earth.
(c) Near the earth’s surface __________air rises up whereas ___________ air comes down.
(d) Air moves from a region of _________ pressure to a region of ___________ pressure.
(e) Air around us exerts __________ in all directions.
(f) Winds carrying ______________ bring rain.
(g) Air _________ on heating while ________ on cooling.
(h) A cyclone is called a __________ in the American continents and __________ in Japan and Philippines.
(i) The word monsoon is derived from the Arabic word _________, which means ‘season’.

Answer:
(a) moving
(b) uneven
(c) warm, cooler

Saturday 17 November 2012

CBSE Class 7 - Science - CH11 - Transportation in Animals and Plants

Transportation in Animals and Plants
Transportation in Animals
Human Heart
(credits:wpclipart)

NCERT Solution, Q & A

Q1(NCERT): Fill in the blanks.

i.     The blood from the heart is transported to all parts of the body by the ___________________.

ii.    Haemoglobin is present in ______________ cells.

iii.   Arteries and veins are joined by a network of ______________.

iv.   The rhythmic expansion and contraction of the heart is called _________________.

v.    The main excretory product in human beings is _____________.

vi.   Sweat contains water and _______________.

vii.  Kidneys eliminate the waste materials in the liquid form called _______________.

viii. Water reaches great heights in the trees because of suction pull caused by _____________.


Answer:

Friday 9 November 2012

CBSE Class 7 - Science - CH16 - Water: A Precious Resource

Water: A Precious Resource
Save Water
credits:openclipart
NCERT Solutions, Q & A

Q1: When 'World Water Day' is celebrated?

Answer: March 22nd.

Q2: What is the main objective of celebrating 'Water Day'?

Answer: We celebrate water day every year to attract the attention of everybody towards the
importance of conserving water.

Q3: How much much amount of water is recommended by UN for daily use by a person?

Friday 28 September 2012

CBSE Class 7 - Science - CH 7 - Weather, Climate and Adaptations of Animals to Climate

Weather, Climate and Adaptations of Animals to Climate
Weather Applet on
your smartphone.
Can you identify weather icons?
NCERT Solution, Q & A, MCQ

Q1(NCERT): Name the elements that determine the weather of a place.

Answer: Following are the important elements that determine weather of a place:
  • Temperature
  • Air pressure
  • Humidity
  • Rainfall
  • Wind Speed

Wednesday 26 September 2012

Science (Quiz) for CTET, Class 6, 7 and 8

Science (Quiz) 
Science Quiz

For CTET (Env. Studies Paper-1), Class 6, 7, 8 and NTSE

Q1: Which of the following is an energy giving food?

(a) Bread
(b) Pulses
(c) Fish
(d) Green Vegetables

Friday 21 September 2012

CBSE Class 7 - Science - CH9 - Soil (#class7Science)(#eduvictors)

SOIL

NCERT Solutions, MCQs, Q&A

Q1(MCQ): In addition to the rock particles, the soil contains

(a) air and water
(b) water and plants
(c) minerals, organic matter, air and water
(d) water, air and plants

Answer: (c) minerals, organic matter, air and water

Q2(MCQ): The water holding capacity is the highest in

(a) Sandy soil
(b) clayey soil
(c) loamy soil
(d) a mixture of sand and loam

Monday 17 September 2012

CBSE Class 7 - Science - CH13 - Motion and Time

Motion and Time
MCQs, NCERT Chapter Solution, Q & A

Q1(MCQ/NCERT): The basic unit of speed is:
(a) km/min
(b) m/min
(c) km/h
(d) m/s

Answer: (d) m/s

Sunday 9 September 2012

Class 7 - Science - CH18 - Wastewater Story

Wastewater Story
Potable Water is Precious
(credits: openclipart)
(NCERT Chapter Solutions and Other Q & A)

Q1: Fill in the blanks:

Answer:

(a) Cleaning of water is a process of removing _pollutants_.

(b) Wastewater released by houses is called _sewage_.

(c) Dried _sludge__ is used as manure.

(d) Drains get blocked by _cooking oil__ and _fats__.

(e) Wastewater is treated in a sewage treatment plant.

(f) Septic tanks, chemical toilets, composting pits are the examples of low-cost sewage disposal systems.

Tuesday 21 August 2012

CBSE Class 7 Science - CH10 - Respiration in Organisms (#eduvictors)(#class7Science)

Respiration in Organisms


NCERT Chapter Solutions and other Q & A

Q1: How breathing is different from respiration?

Answer:
S.No.BreathingRespiration
1It involves the intake of oxygen and release of Carbon dioxide.Respiration is more complex and it includes
breathing as well as oxidation of food in cells to release energy.
2It is a physical process i.e. exchange of gases.It is a biochemical process in which food is broken along with the release of energy.
3It involves breathing organs e.g. lungs in mammals.It occurs at a cellular level


Thursday 2 August 2012

CBSE Class 7 Science - CH14 - Electric Current and its Effects

Electric Current and its Effects
Why CFL is better than electric bulb?
NCERT Solutions and other Q & A

Q1: Draw in your notebook the symbols to represent the following components of electrical circuits: connecting wires, switch in the ‘OFF’ position, bulb, cell, switch in the ‘ON’ position, and battery.

Answer:


















Tuesday 26 June 2012

CBSE Class 7 Science - CH5 - Acids, Bases and Salts

NCERT Chapter Solutions & other Q & A
pH value is used
to indicate acidic, basic or
neutral nature of a
substance.
credits: wikicommons


Q1: State differences between acids and bases.

Answer:

SNo.PropertiesAcidsBases
1.TasteSour TasteBitter Taste
2.Litmus TestTurn blue litmus into red.Turn red litmus into blue
3.Dissolved in waterGive H+ ions (responsible for its acidic nature)Give OH- ions (responsible for its basic nature)
4.Action with
metals
Give Hydrogen GasGenerally do not react.
5.Action with Ammonium SaltDo not reactGive ammonia gas
6.Action with phenolphthaleinDo not give any colour.Give pink colour
7.Action with methyl orangeGive red colour.Give yellow colour.
8.Absorb Carbon dioxideDo not absorb CO2 gas.Some bases like NaOH absorb CO2 gas.
9.Naturally FoundVinegar, Curd, Citrus fruits, HCl etc.Lime Water, Soap, Milk of Magnesia etc.


Sunday 20 May 2012

Class 7 - Science - CH4 - Heat



NCERT Solution and Q & A


Q1: Define Heat.
Answer: Heat is a form of energy which produces a sensation of hotness or coldness. It is measured in Joules (J) or in Calories. Heat energy flows from one body to another due to temperature difference between the two. Heat is an internal energy of the substance due to molecular motion of the substance.

Sunday 13 May 2012

Class 7 - Science - CH3 - Fibre To Fabric

NCERT Chapter Solutions and Q & A

Sources of Wool
(image credits: openclipart.org)
Q1: You must be familiar with the following nursery rhymes:
(i) ‘Baa baa black sheep, have you any wool.’
(ii) ‘Mary had a little lamb, whose fleece was white as snow.’

Answer the following:
(a) Which parts of the black sheep have wool?
(b) What is meant by the white fleece of the lamb?

Thursday 3 May 2012

class 7 - Science - Ch6 - Physical and Chemical Changes

NCERT Solutions and other Q & A


Melting of Ice Cream (Physical Change)
(Source: openclipart.org)
Q1: What do you mean by physical properties of matter?

Answer: A physical property can be measured and observed without changing the composition or identity of a substance. E.g. Odour, colour, volume, state (gas, liquid, or solid), density, melting point, and boiling point are physical properties of a substance.

Q2: What do you mean by physical changes?

Answer: Physical changes are changes in the physical properties of substances. No new substances are formed in these changes. These changes may be reversible. E.g. melting of ice.


Saturday 21 April 2012

Class 7 - Science - Ch2 - Nutrition in Animals

NCERT Text book Solutions and other Questions and Answers


Q1: Fill in the blanks:
Answer
(a) The main steps of digestion in humans are ingestion, digestion, absorption , assimilation and egestion.

(b) The largest gland in the human body is liver.

(c) The stomach releases hydrochloric acid and digestive juices which act on food.

(d) The inner wall of the small intestine has many finger-like outgrowths called villi.

(e) Amoeba digests its food in the food vacuole .

Q2: Mark ‘T’ if the statement is true and ‘F’ if it is false:
Answer:
(a) Digestion of starch starts in the stomach. (T/F) : False. It starts in the mouth
(b) The tongue helps in mixing food with saliva. (T/F) : True
(c) The gall bladder temporarily stores bile. (T/F) : True
(d) The ruminants bring back swallowed grass into their mouth and chew it for some time. (T/F) : True

Q3: Tick () mark the correct answer in each of the following:
Answer:

(a) Fat is completely digested in the(i) stomach
(ii) mouth
(iii) small intestine  (√)
(iv) large intestine

(b) Water from the undigested food is absorbed mainly in the
(i) stomach
(ii) foodpipe
(iii) small intestine
(iv) large intestine (√)

Q4: Match the items of Column I with those given in Column II:
Answer:
Carbohydrates - Sugar
Proteins           - Amino acids
Fats                 - Fatty acids and glycerol


Saturday 14 April 2012

class 7 - Science - Ch1 - Nutrition in Plants

Nutrition in Plants


Q1: Why do organisms need to take food?

Answer: All organisms take food and utilise it to get energy for the growth and maintenance of their bodies.

Q2: Why do plants use the nitrogen present in soil? How is this nitrogen replenished in the soil?

Answer: Plants cannot absorb nitrogen in gas form; they need it in soluble form. Therefore, they use the nitrogen present in soil to prepare proteins.

Atmospheric nitrogen is fixed in soil by nitrogen-fixing bacteria such as Rhizobium,which live in the root nodules of leguminous plants such as gram, peas, beans, etc. In return, the plants provide food and shelter to the bacteria.


Monday 26 December 2011

Explore Biodigital Human Body in 3D

Explore Biodigital Human Body in 3D


The website BioDigitalHuman provides interactive 3D Human body and anatomical systems views.
Explore Biodigital Human Body in 3D (#humanbody)(#eduvictors)

To view the website you need a browser supports HTML5 and WebGL. Chrome supports these. I think you need to install plugins in Firefox and IE9+. You need a broadband connection to view the site. No doubt it has been the award winning site.

Wednesday 2 November 2011

NTSE (SAT Quiz-3)

NTSE (SAT Quiz-3)


Q1: Which of the following is an antibiotic?
       a. Aspirin
       b. Penicillin
       c. Paracetamol
       d. Sulphadizine

Q2: Digestion of food starts in:
       a. mouth
       b. liver
       c. stomach
       d. intestines

Q3: By taking the pulse rate of the human body, a doctor determines
       a. heartbeat
       b. functioning of heart valves
       c. condition of lever
       d. functioning of lungs

Q4: A thermostat is used to
       a. purify air
       b. regulate humidity
       c. regulate temperature
       d. regulate air pressure

Q5: Heat from the sun reaches the earth by
        a. reflection
        b. conduction
        c. convection
        d. radiation

Q6: Dew forms most readily on nights that are:
        a. calm and clear
        b. stormy
        c. windy
        d. cloudy

Q7: The full moon rises in the
        a. east
        b. west
        c. south
        d. north

Q8: An aeroplane is able to fly because
       a. it is lighter than air
       b. it is heavier than air
       c. it is made up of very light material
       d. moving air can lift objects

Q9: The souring of milk is caused by the action of
        a. protozoan
        b. bacteria
        c. virus
        d. fungus

Q10. The smallest thing that can cause disease in the human body is
         a. flea
         b. bacteria
         c. protozoa
         d. virus

Q11: The most abundant gas in the air is:
         a. oxygen
         b. carbon dioxide
         c. nitrogen
         d. hydrogen

Q12: Which element is common between brass and bronze
         a. copper
         b. Iron
         c. Zinc
         d. Aluminium

Q13: The densest element known so far is
         a. gold
         b. mercury
         c. osmium
         d. tungsten

Q14: The most ductile element is
         a. gold
         b. silver
         c. iron
         d. aluminium

Q15: The metal having the highest melting point is
         a. chromium
         b. tungsten
         c. diamond
         d. Silver


Answers: 1-b     2-a     3-a     4-c    5-d     6-a     7-a    8-d    9-b    10-d
                11-c    12-a   13-c    14-a   15-b

See other quizes at link1, link2, link3

Sunday 23 October 2011

CBSE Class 7 - Science - Light - Questions & Answers

Class 7 - Ch 15 - Science - Light - Questions & Answers

Question1: Fill in the blanks
a. An image that cannot be obtained on a screen is called ______.

b. Image formed by a convex _______ is always virtual and smaller in size.

c. An image formed by a __________ mirror is always of the same size as that of the object.

d. An image which can be obtained on a screen is called a _________ image.

e. An image formed by a concave ___________ cannot be obtained on a screen.

Answers:
1 a) virtual image
b) convex mirror
c) plane
d) real
e) concave lens
 

Question2: Mark ‘T’ if the statement is true and ‘F’ if it is false:
(a) We can obtain an enlarged and erect image by a convex mirror. (T/F)
(b) A concave lens always form a virtual image. (T/F)
(c) We can obtain a real, enlarged and inverted image by a concave mirror. (T/F)
(d) A real image cannot be obtained on a screen. (T/F)
(e) A concave mirror always form a real image. (T/F)

Answers: a-false b-true c-true d-false e-false

Friday 21 October 2011

Class 7 - Science Chapter 15 - Light

 Class 7 - Science Chapter 15 - Light

1. Light travels along straight lines. This property is called rectilinear propagation of light.

2. Any polished or a shining surface acts as a mirror.

3. Change in direction of light from an object is called reflection of light.

4. An image which can be obtained on a screen is called a real image.

5. An image which cannot be obtained on a screen is called a virtual image.

6. The image formed by a plane mirror is erect. It is virtual and is of the same size as the object. The image is at the same distance behind the mirror as the object is in front of it.

7. In an image formed by a mirror, the left side of the object is seen on the right side in the image, and right side of the object appears to be on the left side in the image. This property is called Lateral Inversion.