7th Forest products and Waste management [Science class VII]

Holy faith abc of Science

I. Long answer type question

1. What are different ways of solid waste disposal?      

Ans : Following are different ways of solid waste disposal

(a)Solid waste is burnt and ash is removed from time to time

(b)Solid waste is buried in low lying area to level uneven ground

(c) Domestic solid waste are buried in a pit to make compost

(d)Non biodegradable solid wastes are recycled and reused

2. Why are forests such a valuable resources?

Ans: Forest product play vital role in socio-economic development. We get food (cereals, pulses, fruits), firewood, fibre, construction material, industrial products (tannins, lubricants, dyes, resins, perfumes) and products of medicinal importance.  It is also the home of diverse wildlife which maintains the ecosystem. Thus forests are valuable resources.

 3. List the various ways in which we can conserve forest?           

Ans: The various ways in which we can conserve forest are:

(i)Deforestation should be compensated by Afforestation.

(ii) Discourage the uses of firewood

(iii)By controlling forest fire applying anti-fire solution

(iv)Controlling overgrazing

(v) Educating people about the importance of forest.

4. List some uses of forest?

Ans: some uses of forest are:

(i) Forest purifies air and prevent air pollution

(ii)Forests recycle water into atmosphere

(iii) Forest bind soil and prevent soil erosion.

(iv) Forest gives us food, timber and medicinal materials

5. What are the techniques of waste management?

Ans: Following are the techniques of waste management

(i) Reduce consumption or find its substitute

(ii)Try to reuse it again and again in other form

(iii) Recover material for recycling

(iv)  Produce energy from the waste,

 II. Short answer type questions

1. How can an individual contribute in improving the quality of life?

Ans: An individual can contribute in improving the quality of life by :

(i)By thinking globally and act personally.

(ii) Joining hand with other to sustain and heal the earth.

(iii) By learning the how nature we are dependent on each other.

(iii) By giving protection and respect to every organism

2. List some problem caused by deforestation?

Ans: (i) Ecosystem and the ecological balance get disturbed.(ii)There is increase in global warming

(iii)Soil erosion will increases

(iv) Wild life may  not survive for long time.  

3 . What is waste management?

Ans: Waste management is the process of collection, transportation and disposal of waste materials.                                                                                                                                   

4. How is sea wage treated?  

Ans:   Treatment of sewage includes removal of solid waste from sewage and making liquid part less harmful.  In sewage treatment plant at first large solid material are removed by passing through vertical bars.  Now Liquid waste left is made to pass settling tank small sized solid impurities live sand or gravel are removed. After this, water is sent to sedimentation tank to separate organic waste. At last left water is chlorinated before releasing into water bodies.
5. How plants and animal interdependent?

Ans: Plants produce food using co₂ given by animals where as oxygen given by plant is used by animals. Animal help plant in pollination and dispersal of seeds and plant provide valuable food and medicinal product. Plants give shelter for animals where as animals excreta provide mineral for growth. Thus we can say that plants and animal interdependent.

III. Very short answer type questions

1. What is food chain?

Ans: A Food chain is a series of organisms depending on next one to feed upon.

2. What do you mean by planed harvesting of forest?

Ans: Use of modern management system that ensures that forest values will be protected during harvesting is called planed harvesting.

3.”You conserve forest, you conserve soil” Justify this statements.

Ans: Forests bind soil with roots and prevent soil erosion. They maintain fertility of soil and check flood.

4. Which should be bigger: those used for sea wage disposal or those used for storm water disposal?

Ans: storm water disposal            

5. Write short notes on: (a)Industrial effluent  (b) Sewage treatments (c) Forest conservation (d)Rainwater harvesting

Ans:

(a)Industrial effluent: The water discharged by the industries into drains and river that causes water pollution is called Industrial effluent.

(b) Sewage treatments: Treatment of sewage includes removal of solid waste from sewage and making liquid part less harmful is called Sewage treatments .  

 (c) Forest conservation: Management, protection and wise use of forest resources is called Forest conservation.

(d) Rainwater harvesting: The practice of storing rain water for further use is called rainwater harvesting. 
6. Distinguish between- (a) flora and fauna (b) tropical evergreen forest and deciduous forest.

(c) Thorn forest and mangrove forest.

Ans: (a) Flora and fauna is the term given to the plant life and animal life respectively. Their interactions comprise the ecosystem and the biodiversity on the planet earth. Hence, they are obviously inter-related.

(b)An temperate evergreen forest is a forest consisting entirely or mainly of evergreen trees that retain green foliage all year round. Deciduous trees lose their leaves in fall. The natural decaying of the fallen leaves enriches the soil and supports all kinds of plant and animal life.

 (c)The thorn forests are found in the region getting rainfall less than 70 cm . Mangrove Forests are found in the delta regions. The trees in the mangrove forests have roots completely submerged in water. They are dense and provide hard and durable timber

7. What are crown and Canopy?       

Ans: The part of the tree with branches is known as the crown. When the crown of tall trees in the forests forms a roof-like covering over the other plants, it is known as a canopy.

8. What is desertification?

Ans: The process by which fertile land becomes desert, due to drought, deforestation, or inappropriate agriculture is called desertification.

IV. Fill in the blanks

(a)The loss of ------- is the greatest threat of wildlife. [Forest]

(b)Sea water is unfit for ------------- purpose. [domestic]

(c) Waste is a material having no ------------ utility. [further]

(d)The sewage systems were ------- type in olden days.[three]

(e)Discharge of waste water from industries is known as ------------- [Industrial effluent]

NCERT/CBSE -7th Science Assignment Chapter –Waste Water Story

Q1) Fill in the blanks:-

(a) The World Water Day is on __________.

(b) The activated sludge is about __________ water.

(c) Water is disinfected by using chemicals like __________ and __________.

(d) __________ and __________ are water borne diseases

(e)The sewage system were ------ type in olden days.

Q2) What is sewage? What does it contain?

Q3) Give two examples of organic and inorganic impurities present in sewage.

Q4) What is meant by waste water?

Q5) How many processes are involved in the treatment of waste water? Name them.

Q6) What is the function of the bar screen used in a Wastewater Treatment Plant?

Q7) What is sludge?

Q8) What is clarified water? Explain.

Q9) What is the difference between aerobic and anaerobic bacteria?

Q10) Give reasons

a. Eucalyptus trees are grown all along sewage ponds.

b. Used tea leaves, solid food remains, cotton etc. should be thrown in the dustbin.

c. Large amount of waste generated at public places must be disposed off properly.

d. Untreated human excreta is a health hazard.

Ans:

a) Eucalyptus trees are grown near sewage ponds as they can grow in contaminated soils and soil containing high amount of salt and organic matter. Also, they absorb the metals, organic matter, nutrients and water from the sewage.

b) These wastes choke the drains. They do not allow free flow of oxygen. This hampers the degradation process.

c) Large amount of waste generated at public places must be disposed off properly otherwise epidemics could break out. 

d) Since a very large fraction of our people defecates in the open, on dry riverbeds, on railway tracks, near fields and many a time directly in water.It may cause water pollution and soil pollution

Q11) Write a short note on “vermiprocessing toilet”.


Q12) What can we do to reduce the load of pollutants in waste water and the pressure on Wastewater Treatment Plant?


Q13) Each tree can make its own manure. How?


Q14) How is sea wage treated?


Q15) What are the technique of waste water managements?


CBSE 7th Waste Water Story management Solved Test Paper Click here


CBSE 7th Waste Water Story management Solved questionsr Click here

VII Biology Ch. respiration in plants and animals Solution of Extra score questions

VII Biology Ch. respiration in plants and animals For scoring students

1.Q. why we breathe faster after a hard work?

Ans: We breathe faster after a hard work for more energy that is fulfilled by fast respiration.

2.Q. What are difference between breathing and respiration?

Ans: Differences between breathing and respiration are:

Breathing

1. It is a physical process because only the air moves from one place to another. 2. During this, energy is not released. 3. It involves breathing organs.

Respiration

1. It is a chemical process because the food undergoes chemical changes. 2. During this, energy is released. 3. It takes place in living cells.

3.Q. Distinguish between respirations from photosynthesis?

Ans: Respiration

1. It takes place throughout day and night. 2. All living organisms do it. 3. Food is consumed. 4. During this process oxygen is taken in and carbon dioxide is given out.

Photosynthesis

1. It takes place during day time.  2. Only green plants do it. 3. Food is synthesized. 4. During this process carbon dioxide is taken in and oxygen is given out

4.Q. what is the difference between the burning of food in cells and burning of wood?

Ans: Respiration

1. It takes place in living cells. 2. Heat energy is liberated. 3. Energy is released step by step in small quantity.

Burning of wood

1. It takes place outside. 2. Heat and light energy are liberated. 3. Energy is released all of a sudden in large quantity.

5.Q. How diaphragms help in breathing?

Ans: As we breathe in, the diaphragm moves down and ribs move up or expands. This movement increases space in our chest cavity.  Then the air rich in oxygen rushes into our lungs from outside. As we breathe out, the diaphragm moves up to its original place and ribs move down. This reduces the size of the chest cavity and air is pushed out of the lungs through bronchi, trachea and nose.

6. Q. why we sneeze?

Ans: We sneeze when dust enter and irritate the nasal cavity. A sneeze expels unwanted harmful particles from the nasal cavity.

7.Q. Why we get muscle cramps after heavy exercise?

Ans:  The anaerobic respiration takes place in the muscle cells during exercise to fulfill the excess demand of energy and produces lactic acid  causes muscle cramps.

8.How much air lung hold of a normal people?

Ans: 3500 ml

9. Q.How many alveoli are in our lungs?

Ans: About 300 millions

10. What is lungs

Ans: Lungs is spongy, pink and elastic respiratory organ.

11. What is the function of epiglottis

Ans: Epiglottis prevents food to enter in wind pipe and work as guars between larynx and pharynx.

Q.12. Why it is advised to breathe through nose not through mouth?

Ans: In nose there are mucus and nose hair that filter air before entering in trachea .so it is advised to breadth through nose only.

Q.13. Why do plant do not have respiratory system?

Ans: Plant respiration is limited by the process of diffusion and nutrients and gases diffuse directly  thus have no need of special organ and organ system.

Q. 14.How fishes breathe under water?

Ans: Fishes use gills to breathe oxygen dissolved in water .Gills are well supplied with blood vessels for exchange of gases..

Q. 15.Aquatic plants do not have stomata. So, how does exchange of gasses take place in them?

Ans: In submerged plants the exchange of gases take place through body surface while in floating plants the stomata are present on the upper surface of leaf.

Q. 16.Why do we yawn when we are sleepy?

Ans: Our body induce yawning to drawn in more oxygen or remove a build-up of carbon dioxide. we yawn to gather a large amount of oxygen for our brain, to help it function faster

Q.17. What do you mean by vital capacity? What is the vital capacity of a normal human being?

Ans: Maximum amount of air a person can breathe in/out after a forceful expiration/inspiration is called vital capacity .In men its value is approximately 4.8 litres while in females, it is approximately 3.5 litres.

7th Respiration in animals and plants:CBSE Class VII MCQ Fiil in the blanks

Class VII Chapter –Respiration in Plants and animals: Fill in the blanks

1. Bacteria and fungi can respire --------------

Ans: Anaerobically

2. --------------is one- celled fungus and respires anaerobically toproduce alcohol

Ans: Yeast

3. The respiration which takes place in the absence of oxygen is called -------------------

Anaerobic respiration

4. Anaerobic respiration takes place in our skeletal muscles and produce --- alcohol

Ans: Ethyl

5. The respiration which takes place in the presence of oxygen is called ------------

Ans: Aerobic respiration

6. The process of oxidation of food to release energy  from absorb food in living cells is called ----------

Ans: respiration or cellular respiration.

7. In cockroaches air enters the body through  ------

Spiracles

8. During heavy exercise, we get cramps in the legs due to the accumulation of ---------

lactic acid

9. As we breathe in, the diaphragm moves -------- and ribs move up or expands

Downward

10. Below the lungs is a strong, fl at sheet of muscle called --------

Diaphragm.

11. Each bronchus enters the lungs and divides into small tubes bronchioles which end up in air sacs called -------

Alveoli

12. The walls of alveoli are supplied with thin blood vessels called -------

Capillaries

13. Frogs breathe through their  -------- as well as their lungs.

skins

14. during exhalation, the ribs moves ----, as the diaphragm moves up to its original place

Ans:  downward

15. In unicellular and smaller multicellular animal’s exchange of gas takes place by ---------

Diffusion

16. Exchange of gases takes place in insect through -------into trachea.

Spiracles

17. plants breathe through tiny pores in the leaves called ---------

Ans: stomata.