Class 8 lesson 3 important question

Q1: A synthetic fibre is a chain of small _____________ joined together.
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Q2: Give examples of some natural and man- made fibres.
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Q3: Define synthetic fibres.
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Q4: Define polymer
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Q5: Cellulose is made up of large number of___________________ units.
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Q6: What is artificial silk?
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Q7: Name the source of rayon.
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Q8: Define nylon fibre.
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Q9: Write down few properties of nylon.
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Q10: Name some articles used in our day to day life made from nylon.
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Q11: Polyester fabrics do not get__________________ easily.
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Q12: Give example of polyesters.
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Q13: Tick the correct answer
Acrylic is used to make

• Penicillin
• Alcohol
• Nitrate
• None of these

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Q14: What happens when synthetic fibres catch fire?
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Q15: Define petrochemicals.
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Q16: State few properties of plastics.
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Q17: Name some articles made from plastics
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Q18: Give examples of thermoplastics.
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Q19: Give examples of thermosetting plastics.
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Q20: Which one is good conductor of electricity: Bakelite or melamine?
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Q21: Why we prefer plastic containers for storage of items like water, milk, pickles, dry food?
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Q22: Plastics are poor conductor of ______________ and ____________________.
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Q23: What is Teflon?
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Q24: What do you mean by fire proof plastics?
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Q25: What do you mean by biodegradable?
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Q26: What do you mean by non-biodegradable?
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Q27: Paper is biodegradable or non- biodegradable?
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Q28: Why should we use a cotton carry bag or jute bag while going to market?
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Q29: Why plastic articles are available in all shape and size?
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Q30: Can all plastic articles be bent easily?
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Q31: Illustrate various uses of thermoplastic andthermosetting plastics.
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Q32: Name the fibre having properties similar to that of silk.
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Q33: Tick the right answer
Nylon fibres are used for making

• Ropes for rock climbing
• Parachutes
• Socks
• All of the above

Class 7 th lesson 3 important question

Q1: Wool is obtained from __________________ of sheep or yak.
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Q2: Silk fibres are obtained from cocoons of _________________.
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Q3: Name some animals which provide us with wool.
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Q4: Yak wool is common in
Tibet
Ladakh
Both a and b
None of these.
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Q5: Name the place where Angora goats are found in plenty.
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Q6: Name some Indian breed of sheep.
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Q7: Kashmiri goat's under fur is woven to form fine shawls called __________________.
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Q8: The fur on the body of camel is also used as wool .True/False.
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Q9: Which parts of the black sheep have wool?
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Q10: Name the protein which is the chief component of wool fibres.
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Q11: Name the process involved in getting fibres form the sheep.
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Q12: Define sericulture.
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Q13: Caterpillars should be collected from bare hand or not?
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Q14: Name the country which is the largest producer of silk.
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Q15: Silk is a good conductor of heat or poor conductor of heat?
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Q16: What is yarn?
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Q17: ______________is a dried perspiration found in raw wool.
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Q18: What is ginning?
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Q19: Spinning is a process of making fibers. True/False.
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Q20: Weaving yarn makes a piece of fabric. True/False
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Q21: Polyester is a natural fibre. True/False.
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Q22: Name a strongest variety of silk.
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Q23: Define weaving.
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Q24: Define spinning.
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Q25: Name the most common silk moth.
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Q26: Name some varieties of silk.
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Q27: ______________ weaves silk threads into silk cloth.
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Q28: What do you mean by cocoon?
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Q29: Name two animals of South America that yields wool.
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Q30: Which of the following does not yield wool?

• Yak
• Camel
• Woolly dog
• Goat

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Class 7 lesson 2 important question

Q1: Name the largest gland in the human body.

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Q2: Animal nutrition includesNutrient requirementsMode of intake of foodUtilisation of food in bodyAll of the above.

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Q3: Define digestion.

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Q4: Name the parts of alimentary canal.

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Q5: Name the glands that secrete digestive juice.__________________.

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Q6: The process of taking food into the body is called ______.

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Q7: We chew food with ________ and break it mechanically into small pieces.

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Q8: Name the different types of teeth.

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Q9: The saliva breakdown starch into sugars.True/ False.

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Q10: Kids of three years age have _________ teeth.

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Q11: Name the type of food of ant

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Q12: Name the type of food of mosquitoes True / False

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Q13: Name the mode of feeding of ant and mosquitoes.

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Q14: Amoeba digests its food in the ____________.

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Q15: The tongue helps in mixing food with the saliva. True/ False.

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Q17: Name some ruminants.

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Q18: Name the finger like projection present in the inner wall of the small intestine

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Q19: Name the organ responsible for removal of undigested and unabsorbed residues from human body.

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Q20: Bile juice is stored in a sac called___________________

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Q21: Bile is responsible for the digestion ofFatProteinVitaminsBoth a and bNone of these

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Q22: What is the location of pancreas?

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Q23: The pancreatic juice acts onCarbohydratesFatsProteinsAll of the above

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Q24: Name the end products of carbohydrates.

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Q25: Name the end products of fats.

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Q26: Name the end products of proteins.

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Q27: Large intestine receives digested and absorbed food. True/ False.

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Q28: Define egestion.

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Q29: What are the causes of diarrhoea in human beings?

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Q30: What is the full form of ORS?

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Q31: How food is pushed down from mouth to stomach?

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Q32: Human can digest cellulose. True/False.

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Q33: The digestion of cellulose takes place in ____________ present in all ruminants.

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Q34: Amoeba uses____________ for movement and capture of food.

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Q35: Name the part of digestive canal involved in absorption of food.

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Q36: Name the part of digestive canal involved in complete digestion of food.

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Q37: Name the part of digestive canal involved in killing of bacteria.

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Q38: Name the part of digestive canal involved in formation of faeces.

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Q39: Name the part of digestive canal involved in chewing of food.

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Class 7 lesson 1 important question

Q1: Name some components of food.

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Q2: Define nutrients.

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Q3: Give an example of autotrophs.

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Q4: Give an example of heterotrophs.

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Q5: Plants prepare their food by using raw materials present in ______________.

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Q6: What do you mean by nutrition?

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Q7: Name the food factories of plants.

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Q8: Name the tiny pores present on the surface of leaves.

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Q9: Name the green pigment present in leaves.

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Q10: ____________ helps leaves to capture the energy of sunlight

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Q11: Why photosynthesis is named so?

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Q12: Sun is the ultimate source of energy for all living organisms. True / False

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Q13: Where does the nucleus of cell lies?

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Q14: State the equation for the process of photosynthesis.

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Q15: The nucleus in a cell is surrounded by a jelly like substance called _______.

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Q16: Why algae present in stagnant water bodies are green in colour?

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Q17: Name a component of food other than carbohydrate synthesise by plants.

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Q18: Name some insectivorous plants.

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Q19: In saprotrophic mode of nutrition organisms take in nutrients fromOxygen maskWater maskPollution maskNone of these

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Q20: During photosynthesis plants take in ___________ and releases ___________.

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Q21: Some organisms live together and share shelter and nutrients, this type of relationship is called

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Q22: Lichen is a symbiotic association between ______ and fungi.

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Q23: Name the edible fungi.

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Q24: Name the organism responsible for converting atmospheric nitrogen into soluble forms.

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Q25: Where we can see Rhizobium bacteria?Dead matterDecaying matterBoth a and bNone of these

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Q26: Give an example of parasites.

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Q27: Give an example of saprotrophs.

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Q28: Amarbel is an example ofParasiteHostAutotrophsSaprotrophs

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Q29: Carbon dioxide is released during photosynthesis. True/ False.

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Q30: During photosynthesis solar energy is converted into chemical energy. True/ False.

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Q31: The product of photosynthesis isCarbohydrateProteinFatsAll of these

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Q32: Name a plant that has both autotrophic and heterotrophic mode of nutrition.

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Q33: Name a parasitic plant with yellow, slender and tubular type of stem.

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Q34: Name the pores present in leaves through which exchange of gas takes place.

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Q35: Animals are autotrophs. True/ False.

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Class 8 lesson 2 important question

Q1: Microorganisms are too small that they can be seen with the help of ______________.
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Q2: Microorganisms are classified into four major groups. Name them.
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Q3: Define virus
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Q4: Name some diseases caused by protozoa.
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Q5: Name some diseases caused by bacteria.
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Q6: Bacteria are of spiral shape as well as ____________________.
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Q7: Name some viral diseases.
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Q8: Give example of single cellular and multicellular microorganisms.
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Q9: Name some friendly microorganisms.
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Q10: Name some harmful microorganisms.
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Q11: Alcohol is produced with the help of ____________________.
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Q12: Tick the correct answer
Which of the following is an antibiotic?

• Penicillin
• Alcohol
• Nitrate
• None of these

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Q13: Define fermentation.
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Q14: Define antibiotics.
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Q15: What do you understand by antibodies?
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Q16: Several diseases like tuberculosis, smallpox and hepatitis can be prevented by ___________.
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Q17: Name some biological nitrogen fixers.
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Q18: Define pathogens.
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Q19: What do you mean by communicable diseases?
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Q20: Name some communicable diseases.
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Q21: Name some organisms which act as carriers of disease causing microbes.
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Q22: Female Anopheles mosquito carries the parasite of ____________________.
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Q23: Female______________ mosquito acts as carrier of dengue virus.
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Q24: Why we should not let water collect anywhere in our neighbourhood?
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Q25: Name some microorganisms that cause disease in animals.
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Q26: Name some microorganisms that cause disease in plants.
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Q27: Why a person suffers from food poisoning?
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Q28: What are preservatives?
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Q29: Define pasteurisation.
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Q30: Name the bacteria involved in nitrogen fixation and where does it lives?
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Q31: Can we see microorganisms with the naked eye? If not, how can we see them?
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Q32: Alcohol is produced with the help of__________________.
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Q33: Which of the following is prepared by the action of microorganism?
Manure
Fertilizer
Both of them
None of these
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Q34: Name the person who discovered fermentation and vaccine for small pox.
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Q35: Name some food preservatives.
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Class 8 lesson 1 important question

Q1: Tick the right answer
We get our food from

• Plants
• Animals
• Both plants and animals
• None of these

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Q2: The same kind of plants grown and cultivated at one place on large scale is called_________.
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Q3: Is crop production and management is important to provide food for a large number of population?

• Portuguese
• English
• Dutch
• Spanish

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Q4: Define crop.
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Q5: Name some crop plants.
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Q6: Classify crops on the basis of seasons in which they are grown.
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Q7: Define kharif crops with examples.
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Q8: Define rabi crops with examples.
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Q9: Why can paddy not be grown in winter season?
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Q10: Ploughing is done by ___________________.
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Q11: Hoe is a simple tool which is used for removing ________________.
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Q12: What is seed drill?
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Q13: What do you mean by good quality seeds?
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Q14: What do you understand by manures?
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Q15: Continuous growing of crops makes the soil poorer in certain______________________.
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Q16: What is manuring?
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Q17: What do you understand by fertilisers?
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Q18: Name the bacteria which fix atmospheric nitrogen.
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Q19: Which one is better organic manure or fertilisers?
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Q20: What do you mean by the term irrigation?
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Q21: Name different sources of irrigation.
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Q22: Name the following shown traditional methods of irrigation:

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Q23: Give few examples of weedicides.
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Q24: Is there any harmful effect of weedicides on the person handling the weedicides sprayer?
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Q25: Weedicides sprayer should cover their _________________ and _______________ with a piece of cloth during spraying of these chemicals.
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Q26: Define harvesting.
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Q27: Define threshing.
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Q28: What is a “combine”?
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Q29: What are harvest festivals?
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Q30: What do you mean by animal husbandry?
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class-7 chapter-2

Revision Notes on Nutrition in Animals

Quick Revision


The animals depend upon other plants and animals for their food.


Animal nutrition comprises the mode of taking in the food in the body, nutritional requirements of the body and how animals can utilize their food.


Digestion - it is a process by which animals break down complex food substances in simpler substances.



Different ways of taking the food



Figure 1: Mode of feeding in Animals

Digestion in Humans


The food that we eat passes through a Canal inside our body.


The food is processed and utilized in the body and unused food is collected inside the canal only.


This Canal is often called as the Alimentary Canal or the Digestive Tract.


The canal is divided into different parts:


The Mouth or Buccal Cavity


Food Pipe or Oesophagus


Stomach


Small Intestine


Large Intestine


Anus







Figure 2: Digestive Tract in Humans

There are three glands associated with the alimentary canal that secrete digestive juices that are used to convert the complex food substances into simpler substances.


liver


pancreas


salivary glands



The Digestive System - The alimentary canal and the digestive glands together form a system in the human body which is responsible for the digestion of food in the body. This system is called the Digestive System.

The Mouth or Buccal Cavity



Figure 3: The Mouth or Buccal Cavity


Ingestion - the process of taking in the food through the mouth is called ingestion.


The food is chewed with the help of teeth, saliva and the tongue present in the mouth.


The salivary glands present in our mouth secrete saliva which mixes with the food, moist it and breaks the starch present in the food into sugar.


The tongue present in the mouth helps in mixing the food with the saliva and helps in swallowing it inside the mouth. It also has taste buds which help in identifying the taste of anything that we eat. Besides this, the tongue also helps in talking.



The Teeth

Milk Teeth - In the early childhood a set of teeth growth in children that then fall off after certain age 6 to 8 years. These teeth are called Milk Teeth.

Permanent Teeth - The teeth that grow after milk teeth fall off are called Permanent Teeth. They generally remain during the lifetime of a person or at least until old age.

Different Types of Teeth



Figure 4: Different types of teeth

Tooth Decay –


A gradual damage of teeth is often called tooth decay.


The main cause of tooth decay is the presence of bacteria in the mouth that grow if we do not keep our mouth and teeth clean.


Any leftover food present inside our teeth is broken down by such bacteria.


As a result, an acid is released which damages the teeth slowly.


Tooth decay can cause severe pain and even toothless.


Tooth decay is caused mainly because of eating food with high sugar content, soft drinks and chocolates.





Figure 5: Stages of Tooth Decay

How can we prevent tooth decay?


Clean your teeth with a brush or dental floss at least twice a day


Rinse your mouth after every meal you eat


Do not put a dirty finger or any unwashed food items in your mouth



Food Pipe or Oesophagus


The food pipe starts from the neck region and runs until the chest area in animals.


The food, when the chewed, moves through the food pipe and reach the stomach through this path.


The food moves in download direction in the food pipe.



The Stomach



Figure 6: Stomach


It is the widest part of the alimentary canal.


It's a bag like structure in a flat U shape.


The stomach is connected with the food pipe and the small intestine.


The stomach’s inner lining produces three things:


Mucous: It protects the stomach lining


Hydrochloric Acid: It kills the bacteria present inside the stomach and activates the digestive juices


Digestive Juices: They help in digestion of the food by breaking down the proteins present in the food into simple substances (olympiads)





Small Intestine


It is a highly coiled structure.


The length of the small intestine is almost 7.5m.


The liver and pancreas release digestive juices into the small intestine.


The inner lining of the intestine also secretes some digestive juices on its own.


The small intestine breaks the carbohydrates into glucose, fats into fatty acids and proteins into amino acids.



The Liver


It is a gland reddish brown in colour.


It is known as the largest gland of the human body.


It secretes a digestive juice called bile juice.


The bile juice is stored in the gallbladder.


The bile juice makes it possible for the body to digest the fats.



The Pancreas


It is a cream coloured gland present in the human body.


It secretes pancreatic juice that helps in digestion of fats, carbohydrates and proteins.



How small intestine absorbs food?


Absorption: it is a process by which the digested food enters the blood vessels of the small intestine.


Villi in the intestine: the small intestine contains small finger-like structures called Villi. They increase the surface area of the intestine thereby increasing the amount of absorption. The digested food gets into the blood vessels through villi and then reaches the whole body. (Olympiads)





Figure 7: Villi in Small Intestine


Assimilation: The process by which the organs of the body utilize the digested food and form complex substances which the body needs such as proteins are called Assimilation.



Parts of Small Intestine

The small intestine has been divided into three parts:

1. Duodenum

It is the first part of the small intestine whose main function is to initiate the digestive process. In this process, the food that enters the small intestine from the stomach is mixed with the digestive juices (bile and pancreatic juice) and is further broken down into simpler substances.

2. Jejunum

It is the middle part of the small intestine that contains the villi and hence undergoes absorption and assimilation.

3. Ileum

It is the third and last part of the small intestine that contains villi-like structures. The ileum absorbs vitamin B12, bile acids and any other nutrients present in the food.

The Large Intestine


Any food that is left undigested passes through the small intestine and enters the large intestine.


It is a wide tube-like structure.


It is only 1.5 m long.


The main function of the large intestine is to absorb water and salts from the undigested food.


The rest of the waste, undigested food passes through the rectum.


Egestion: The process by which the waste, undigested food (the faecal matter) get out of the body through the anus.



 What is diarrhoea?


A condition when watery stools appear frequently is called Diarrhoea.


Food poisoning and infection are two main causes of diarrhoea.


It is a serious disease and can lead to death in severe cases because it involves extensive loss of water and salts from the body.


Generally, ORS (Oral Rehydration Solution) which is boiled cooled water in which a pinch of salt or sugar is added is recommended to the patients to maintain the water loss of the body.



Digestion in Grass Eating Animals



Figure 8: Digestive System in Cow


Rumen - It is a sac-like structure present between the food pipe and the small intestine in grass eating animals like cows and buffaloes.


At first, the animals do not chew their food (basically grass) and instead swallow it.


This partly digested food is stored in the rumen.


Cud: The partly digested food present in the rumen is called Cud.


Rumination: The cud returns to the mouth in these animals and then they chew it. This is called Rumination.


Ruminants: the animals that swallow their food at first and then chew it, later on, are called Ruminants.


Grass eating animals can digest cellulose while several other animals cannot. These animals have a different type of bacteria present in the stomach that helps in digesting the cellulose. (Olympiads)



Feeding and Digestion in Amoeba


The Amoeba is a microscopic organism which is made up of only one cell


The Amoeba has a cell membrane, cytoplasm, a nucleus which is round and dense and small vacuoles which are like bubbles present all over it.


The Amoeba is capable of changing its shape and position on its own.


 It uses false teeth called pseudopodia to take in the food present in the surroundings.


Whenever it wants to intake the food the pseudopodia or finger-like projections come out of its body.


The pseudopodia engulf the food in and the food gets stored in the food vacuoles.


Then it secretes some digestive juices inside the vacuoles that help in its digestion of the food.


The Amoeba then absorbs the digested food and uses it for fulfilling different life processes such as multiplication and growth.


The Amoeba also secretes out waste products or undigested food out of its body. (Olympiads)





Figure 9: How amoeba digests the food