some important question and answer of science for class 8
Answers
Answer:
branches of biology
zoology
botany
microbiology
cell biology
physiology
taxonomy
genetics
etc.
Answer:
1.Crop Production and Management:
Question 1.
What is the name of the undesirable plants that grow among the crops?
Answer:
Weeds
Question 2.
Name one weed.
Answer:
Wild oat
Question 3.
Name the methods applied for weeding.
Answer:
Manual methodChemical methodBiological method
2.Microorganisms:
Question 1.
Name the groups in which microorganisms are broadly classified.
Answer:
Microorganisms are broadly classified in four groups:
bacteriafungiprotozoa algae
Question 2.
Name the type of microorganism that is smaller than bacteria.
Answer:
Virus
Question 3.
Write the name of a bacterium that helps in the formation of curd.
Answer:
Lactobacillus
3.Synthetic Fibres and Plastics:
Question 1.
Name a natural fibre.
Answer:
Cotton
Question 2.
Name the basic component of animal fibres.
Answer:
Protein
Question 3.
Name some artificial fibres.
Answer:
Nylon, terylene, PET, acrylic, teflon, etc.
4.Materials: Metals and Non-Metals:
Question 1.
Name some common metals.
Answer:
Copper, aluminium, iron, silver, gold, etc.
Question 2.
Name some common non-metals.
Answer:
Hydrogen, oxygen, carbon, sulphur, phosphorus, etc.
Question 3.
Give examples of metalloids.
Answer:
Antimony, arsenic, silicon, boron, etc.
5.Coal and Petroleum:
Question 1.
Name some renewable sources of energy.
Answer:
Water, wind, solar.
Question 2.
Give some examples of fossil fuels.
Answer:
Coal, petroleum, natural gas.
Question 3.
Name the elements present in coal.
Answer:
Carbon, oxygen and sulphur.