Question

Q.3 Answer the following questions in short: 1) What are weeds? How can we control them? 2) What are the major groups of micro-organisms? 3) Write only two properties of plastics.​

Answer 1

Answer:

1. Weeds are unwanted plants which grows with crop plant and they absorb water, minerals, space, sunlight. some weed may also produce poisonous to plants.
2. Bacteria, protozoa, algae, fungi, viruses
3. electrical conductivity, flammability

Answer 2

Answer 1 -

Weeds are unwanted plants. They grow with crops and compete for nutrients and water with main crop.

Weeds can be controlled using weedicides: It is a chemical, which is sprayed in the fields to kill all available weeds.

Answer 2 -

Microorganisms are classified into four major groups. These groups are bacteria, fungi, protozoa and some algae.

Answer 3 -

• water resistant.
• shock resistant.