Weeds are unwanted plants in a cultivated field. In this context, consider the following statements:
1. The weeds compete for food, space and light.
2. Weeds are responsible for affecting the growth of the crop.
3. Timely sowing of crops and crop rotation help in weed control.
Which of the statement(s) given above is/are correct?
More Questions Selected Just For You. Attempt Now!
Consider the following statements:
1. Anti-viral medicines are harder to make as viruses have biochemical mechanisms of their own.
2. Anti-bacterial medicines target both bacteria and fungi.
Which of the statement(s) given above is/are correct?
Consider the following statements about pesticide residue in our food chain:
1. It is introduced in the food chain by aquatic plants and animals.
2. These chemicals get accumulated progressively at each trophic level.
3. Human body accumulates minimum concentration of these chemicals.
Select the correct answer using the code given below:
Which of the following are the properties of the image formed by a plane mirror?
1. The image is always real and erect.
2. The size of the image is equal to that of the object.
3. The image formed is as far behind the mirror as the object is in front of it.
4. The image is laterally inverted.
Select the correct answer using the code given below.
Water vapour present in the atmosphere is formed due to which of the following factors?
1. Heating of water bodies.
2. Activities of living organisms.
3. Weathering of rocks.
4. Photosynthesis.
Select the correct answer using the code given below:
In context of Air pollution in India, consider the following statements:
1. Presence of high levels of pollutants in air causes visibility to be lowered.
2. Formation of smog is a visible indication of air pollution.
3. Oxides of nitrogen and sulphur dissolve in rain to give rise to acid rain.
Which of the statement(s) given above is/are correct?
Unicellular organism are unique because they are made up of a single cell only. Which of the following is/are examples of unicellular organisms?
1. Amoeba
2. Yeast
3. Bacteria
Select the correct answer using the code given below:
In the question given below, there are two statements marked as Assertion (A) and Reason (R). Read the statements given below carefully:
Assertion (A): The Sun at the sunrise or the sunset appears red whereas at noon, the Sun appears white.
Reason (R): Light from the Sun near the horizon passes through larger distance in the earth’s atmosphere than the light from the Sun overhead.
Choose the correct answer using the codes given below:
If an opaque object on the path of light becomes very small, light has a tendency to bend around it and not walk in a straight line. This effect is known as:
Consider the following statements:
1. The ‘danger’ signal lights are red in colour as the red is least scattered by fog or smoke.
2. The sky appears dark to passengers flying at very high altitudes because of scattering of light.
Which of the statements given above is/are correct?
In the Animal Kingdom, which of the following groups of organisms shows the highest level of cellular organisation?
1. Annelids
2. Sponges
3. Coelenterates
Choose the correct answer by using the codes given below: