Class-9 Sciene Chapter-7 Diversity in Living Organism

 EVENTS CONVENT H. SCHOOL

05/02/2021             CLASS-9                   SLOT-2
Science
Chapter-7 Diversity in Living Organism

_______________________________________

 Page 80
Question 1. Why do we classify organisms?

Answer: For easier and convenient study we classify organisms.

 Question 2. Give three examples of the range of variations that you see in life-forms around you.

Answer:

(a) Small cat and big cow

(b) Grass and banyan tree

(c) Black crow and green parrot

 

Page 82

Question 1. Which do you think is a more- basic characteristic for classifying organisms?

(a) the place where they live.

(b) the kind of cells they are made of. Why?

Answer: Classification based on living place is more basic as there can be wide variations in organisms living in a given place.

 Question 2. What is the primary characteristic on which the first division of organisms is made?

Answer: Nature of cell is the primary characteristics on which the first division of organisms is decided. Based on this criterion life forms can be classified into prokaryotes or eukaryotes.

 Question 3. On what bases are plants and animal’ out into different categories?

Answer: Mode of nutrition and presence or absence of cell walls.

 

Page 83

Question 1. Which organisms are called primitive and how are they different from the so-called – advanced organisms?

Answer: Organisms with simple cellular structure and no division of labour are called

primitive. Advanced organisms, like mammals have millions of cells and there are different organs and organ system for different biological functions.

 

Question 2. Will adiKznced organisms be the same as complex organisms? 

Answer: Yes, advanced organisms means greater degree of evolution which leads to more complexity.

 
Page 85

Question 1. Whaf is the criterion for classification of organisms as belonging to kingdom Monera or Protista?

Answer: It is the presence or absence of a well defined nucleus. Monera has no nuclear membrane, while Protista shows well defined nucleus.

 Question 2. In which kingdom will you place an organism which is single-celled, eukaryotic and

photosynthetic?

Answer: Protista.

 Question 3. In the hierarchy of classification, which grouping will have the smallest number of organisms with a maximum of characteristics in common and which will have the largest number of organisms?

Answer: Organisms belonging to Kingdom Monera will have the small number of organisms with a maximum of characteristics in common. And kingdom Animalia will have the largest number of organisms.

 
Page 88

Question 1. Which division among plants has the simplest organisms?

Answer: Thallophyta or algae.

 Question 2. How are pteridophytes different from the phanerogams?

Answer: Pteridophytes have naked embryo and inconspicuous reproductive organ whereas — phanerogams have well-differentiated reproductive organs and covered embryo.

 Question 3. How do gymnosperms and angiosperms differ from each other?

Answer: Seeds are naked in Gymnosperms and are covered in angiosperms.

Page 94

Question 1. How do poriferan animals differ from coelenterate animals?

Answer:Animals from Porifera show cellular level of organisation, while those from Coelenterata show tissue level of organisation.

In Porifera there is no division of labour, while in Coelenterata some division of labour is seen. Porifera do not have coelom, while coelenterata have coelom.

Question 2. How do annelid animals differ from arthropods?

Answer:

Question 3. What are the differences between amphibians and reptiles?

Answer:

 Question 4. What are the differences between animals belonging to the Aves group and those in the mammalia group?

Answer:

Class-6 Science Chapter-14 Water

 EVENTS CONVENT HIGH SCHOOL

05/02/2021             CLASS-6                   SLOT-2
Science
Chapter-14 Water

                               _______________________________________

 
1.Fill up the blanks of the following:-

(a) The process of changing of water into its vapour is called evaporation or vaporisation

(b) The process of changing water vapour into water is called condensation

(c) No rainfall for a year or more may lead to droughts in that region.

(d) Excessive rains may cause flood

 

2. State for each of the following whether it is due to evaporation or condensation:

(a) Water drops appear on the outer surface of a glass containing cold water. -condensation

(b) Steam rising from wet clothes while they are ironed. -evaporation

(c) Fog appearing on a cold winter morning. -condensation

(d) Blackboard dries up after wiping it. -evaporation

(e) Steam rising from a hot girdle when water is sprinkled on it. -evaporation

 

3. Which of the following statements are “true” Or “false’

(a) Water vapour is present in air only during the monsoon. False

(b) Water evaporates into air from oceans, rivers and lakes but not from the soil. False

(c) The process of water changing into its vapour is called evaporation. True

(d) The evaporation of water takes place only in sunlight. False

(e) Water vapour condenses to form tiny droplets of water in the upper layers of air where it is cooler. True

 

VERY SHORT ANSWER TYPE QUESTIONS

 1. Write the sources of water on the earth.

Ans:  Sources of water on the earth are:

Seas, Oceans, Rivers, Springs, Tubewells, etc.

 2. In which forms, water exists on the earth?

Ans: Water exists on the earth in all three physical forms: ice, water and water vapour.

 3. What is transpiration?

Ans: Loss of water in the form of water vapour through stomata of leaves is called transpiration.

4. How are the clouds formed?

Ans: Clouds are formed by the condensation of water vapour at high altitude.

 5. What is meant by the conservation of water?

Ans: Careful, economical and wise use of water and avoiding the wastage of water is called conservation of water.

 
SHORT ANSWER TYPE QUESTIONS

 1. Mention two main functions of water for living organisms.

Ans: Two main functions of water for living organisms are:

1. Water is essential for the germination of seeds, growth of plants and in photosynthesis.

2. Water is used for the transportation of people and goods.

2. Why is ocean water not suitable for domestic use?

Ans: Sea and ocean water contains large amounts of various salts. It is due to these salts the ocean water is salty and cannot be used for drinking, washing and for irrigation purposes.

 3. Why does the water split on the floor disappear after some time?

Ans:  Due to evaporation the water split is changed into water vapour. So it disappears after some time.

 4. How does heavy rain affect us?

Ans: Heavy rains may cause:

1. A rise of water level in dams, rivers, lakes, etc.

2. Waterlogging and floods.

3. Floods cause damage to property, crops and animals.

 5. How does the failure of rainfall affect people on the earth?

Ans: The failure of rainfall can cause the following:

1.The soil becomes dry.

2. Water level in rivers, lakes, dams, etc. may fall. Ponds and canals may even dry up.

3. The ground water level falls.

 
6. Name two processes responsible for the formation of clouds.

Ans:  Evaporation and transpiration.

 7. During winters why do we see more fog in close areas where there are lots of .trees?

Ans:  Due to lots of trees, air at that place contains much more water vapour during winters. These vapour condense on dust or smoke particles forming thick fog.

 

Class-8 Science Chapter-15 Some Natural Phenomina

         EVENTS CONVENT H.SCHOOL

05/02/2021             CLASS-8                   SLOT-2
Science
Chapter-15 Some Natural Phenomina

_______________________________________

MCQs

Question 1.Like charges when brought near each other then they

(a) repel (√)

(b) attract

(c) sometimes attract and sometimes repel

(d) have no effect

 

Question 2.A device used to test the charge on an object is called

(a) ammeter

(b) electroscope  (√)

(c) seismograph

(d) none of these

 

Question 3.A major earthquake occurred on 8th October 2005 in

(a) Gujarat

(b) Delhi

(c) Haryana

(d) North Kashmir  (√)

 

Question 4.A sudden shaking of the earth lasting for a very short time is known as □

(a) lightning

(b) thunder

(c) earthquake  (√)

(d) Tsunami

 

Question 5.A major Tsunami occurred in the Indian Ocean on

(a) 26th December 2001

(b) 26th December 2002

(c) 26th December 2003

(d) 26th December 2004  (√)

 

Question 6.Instrument used to find the source of seismic waves is known as

(a) seismometer  (√)

(b) voltammeter

(c) galvanometer

(d) ammeter

 

Question 7.Richter scale is used to measure the magnitude of

(a) lightning

(b) charges

(c) earthquake  (√)

(d) rainfall

  

Very Short Questions and Answers:-

Question 1.Why do two charge bodies attract or repel ? [NCT2008]

Answer:When the two bodies have the same charges, they repel each other and when the two bodies have different charges they attract each other.

 

Question 2.Write the one name of method by which object can be charged. 

Answer:Object can be charged by conduction.

 

Question 3.Which of the following cannot be charged easily by friction ? 

 1.A plastic scale.

2.A copper rod. (√)

3.An inflated balloon.

4.A woollen cloth.

 

Question 4.When a glass rod is rubbed with a piece of silk cloth the rod and the cloth both acquire positive charge.

1.becomes positively charged while the cloth has a negative charge. (√)

2.and the cloth both acquire negative charge.

3.becomes negatively charged while the cloth has a positive charge

 

Question 5.Tick T for true and F for false in the following statements : 

1.     Like charges attract each other. (False)

2.    A charged glass rod attract a charged plastic straw. (True)

3.    Lightning conductor cannot protect a building from lightning. (False)

4.    Earthquakes can be predicated in advance. (False)

Question 6.Sometimes, a crackling sound is heard while taking off a sweater during winters. Explain. 

Answer:This crackling sound is heared because due to friction between the hair and sweater the sweater gets charged.

 Question 7.What is meant by earthing ?

Answer:The process of transfer of charges from a charged object to the earth is called earthing.

 Question 8.When does a body become discharged ?

Answer:When a body looses its charges, it is said to be discharged.

Short Questions and Answers

Question 1.Explain why a charged body loses its charge if we touch it with our hand.

Answer:When we touch a charged body with our hand, the body is earthed. This causes the charges flow to the earth and the body looses the charge.

 

Question 2.List three states in India where earthquakes are more likely to strike. 

Answer:Three states in India where earthquakes can occur are Gujarat, Rajasthan and Jammu & Kashmir.

 

Question 3.The weather department has predicted that a thunderstorm is likely to occur on a certain day. Suppose you have to go out on that day. Would you carry an umbrella ? Explain. 

Answer:No, I would not carry an umbrella. The charges produced during a thunderstrom can flow through the umbrella and harm us.

 

Question 4.When a charged plastic straw is brought near a charged plastic straw, there is repulsion between them. What type of charge exists between them ?

Answer:The charge on both the plastic straw are same, since like charges repel each other.

 

Question 5.When a charged balloon is brought near a charged refill, there is attraction between the two. What type of charge exists between the two ?

Answer:The charge on the balloon and a refill are different, because unlike charges attract each other.

 

Question 6.Why is the charging by rubbing known as static electricity ?

Answer:Charging by rubbing is known as static electricity because the charges do not move.

Long Questions and Answers

Question 1.Name the scale on which the destructive energy of an earthquake is measured. An earthquake measures 3 on this scale. Would it be recorded by a seismograph ? Is it likely to cause much damage ?

Answer:The destructive energy of the earthquake can be measured on the Richter scale. Yes, an earthquake measuring 3 would be recorded by the seismograph. This earthquake would not cause much damage.

 

Question 2.Suggest three measures to protect ourselves from lightning. [

Answer:We can protect ourselves from lightning by

switching off and disconnecting all heavy electrical appliances.

Not bathing under running tap water.

Not standing near metallic poles.

 

Question 3.Explain why a charged balloon is repelled by another charged balloon whereas an uncharged balloon is attracted by another charged balloon ? 

Answer:A charged balloon has the same charge as another charged balloon, so there is repulsion between them because like charges repel each other. On the other hand, an uncharged body always attracts a charged body. Therefore, an uncharged balloon is attracted by a charged balloon.

 

Question 4.Apart from disturbance inside the earth, what are the other reasons of earthquake ?

Answer:Earthquakes can also occur due to underground nuclear explosion, or when a volcano erupts, or when a meteor hits the earth.

Question 5.What are weak zones ?

Answer:Since earthquakes are caused by the movements of plates, the boundaries of the plates are weak zones where earthquakes are most likely to occur.

Class-7 Science Chapter-12 Reproduction in Plant

 EVENTS CONVENT H.SCHOOL

05/02/2021             CLASS-7                   SLOT-2
Science
Chapter-12 Reproduction in Plant
_______________________________________

 Q.1.Fill in the blanks:

(a) Production of new individuals from the vegetative part of parent is called vegetative reproduction

(b) A flower may have either male or female reproductive parts. Such a flower is called unisexual flower

(c) The transfer of pollen grains from the anther to the stigma of the same or of

another flower of the same kind is known as pollination

(d) The fusion of male and female gametes is termed as fertilization

(e) Seed dispersal takes place by means of wind and water.

 

Q.2. Describe the different methods of asexual reproduction. Give examples.

Ans. Different methods of asexual reproduction are:

(a) Binary Fission: This process takes place in unicellular organisms. Parent cell elongates and gets divided into two identical daughter cells. Each daughter cell grows into an independent adult.

(b) Endospore Formation: In this method the spore wall is formed around a bacterial cell to form an endospore. This endospore germinates to form an active bacterium under favourable conditions.

(c) Fragmentation: In this process, body of the organism breaks up into two parts. Then each part grows into a new filament thus forming two organisms from a single one.

 (d) Budding: In yeast, new organisms are produced by the bud formation from the parent organism. After growing to full size, the bud gets detached and forms a new independent individual.

(e) Vegetative propagation: When vegetative parts of a plant like stems, leaves and root etc., give rise to new ones, it is.called vegetative propagation.

 

Q.3. Explain what you understand by sexual reproduction.

Ans.Sexual reproduction means involvement of two parents in the process of reproduction. It is found mainly in higher plants where male gamete and female gamete fuse to form a zygote. These zygotes develop into individuals which are not identical. Offsprings inherit the characteristics of both the parents. In sexual reproduction both parents survive after the process of reproduction.

 

Q.4. State the main difference between asexual and sexual reproduction.

Ans.

 Q.5.Sketch the reproductive parts of a flower.

Ans.

Q.6.Explain the difference between self-pollination and cross-pollination

Ans.

 Q.7.How does the process of fertilization take place in flowers?

Ans.When the pollen grain reaches the stigma of a same species flower, it starts

growing out into the pollen tube of the stigma. This tube continues to grow inside the style till it reaches the ovule. Male cells are released into the ovule for the fertilization with the female egg cell and thus the zygote is formed. After this process of fertilization, the ovary develops into fruit and ovule into seeds.

 

Q.8.Describe the various ways by which seeds are dispersed.

Ans. Following are the ways in which the seeds are dispersed:

(i) Some light seeds like that of madar, which are hairy, dry and small are carried away by the wind to different places.

(ii) Spiny seeds and fruits like that of xanthium and urena, stick to the clothes of passers by and animals. These seeds are carried away by these agents to different places.

(iii) In some plants having heavy seeds like that of coconut, water acts as the dispersing agents.

(iv) Some seeds are dispersed with the fruit burst like in case of balsam and castor.

Q.9.Match items in Column I with those in Column II

 

Q.10. Tick (%/) the correct answer:

(a) The reproductive part of a plant is the

(i) leaf (ii) stem (iii) root (iv) flower(√)

(b) The process of fusion of the male and the female gametes is called

(i) fertilisation (√) (ii) pollination (iii) reproduction (iv) seed formation

c) Mature ovary forms the

(i) seed (ii) stamen (iii) pistil (iv) fruit(√)

(d) A spore producing plant is

(i) rose (ii) bread mould (√) (iii) potato (iv) ginger

(e) Bryophyllum can be reproduced by its

(i) stem (ii) leaves (√) (iii) roots (iv) flower