Consider the following statements about ‘Biochemical Oxygen Demand’ (BOD):
1. It is the amount of oxygen required by bacteria to break down the organic matter present in a certain volume of a sample of water.
2. Highly polluted water have BOD value of less than 5 ppm.
Which of the statements given above is/are correct?
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A lemon kept in water in a glass tumbler appears to be bigger than its actual size, when viewed from the sides. This is because of which of the following reasons:
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:
Vaccines are now available for preventing a whole range of infectious diseases. Which among the following infectious diseases are preventable by the use of vaccine?
1. Polio
2. Measles
3. Whooping cough
4. Human Papilloma Virus (HPV)
Select the correct answer using the code given below:
Consider the following statements:
1. Tendons are type of connecting tissue that connect muscles to bones.
2. Nerve impulses are transmitted with the help of tendons throughout our body.
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:
Vectors are living organisms that can transmit infectious pathogens between humans, or from animals to humans. The commonest vectors we all know are mosquitoes. Which among the following vector borne diseases are caused by mosquitoes?
1. Yellow Fever
2. Lymphatic Filariasis
3. Zika Fever
4. Japanese Encephalitis
Select the correct answer using the code given below:
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?
Consider the following statements about ‘Photochemical Smog’:
1. It is a phenomenon of cool humid climate.
2. It occurs when sunlight acts on unburnt hydrocarbons and nitrogen oxides.
3. Ozone in photochemical smog is responsible for the haze.
Which of the statements given above is/are correct?
Consider the following statements about ‘Human Body’:
1. Muscles contain special proteins which contract and relax to cause movement.
2. We can control the movement of all the muscles in our body.
Which of the statement(s) given above is/are correct?
2. Consider the following statements:
1. Typhoid fever in human beings is caused by a virus.
2. Plasmodium is a tiny protozoan responsible for causing malaria.
3. Plasmodium enters the human body through the bite of infected female Anopheles mosquito.
Which of the statements given above is/are correct?