Tag: biology

Questions Related to biology

Which one of the following statements is correct regarding sexually transmitted diseases (STDs)?

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  1. A person may contact syphilis by sharing milk with one already suffering from the disease.

  2. Haemophilia is one of the STDs.

  3. Genital herpes and sickle-cell anaemia are both STDs.

  4. The chances of a 5-years boy contracting a STD are very rare.

Show answer
Correct Option: D
Explanation:

Syphilis is caused by bacterium Treponema pallidum. It is a sexually transmitted disease (STD) which is transmitted through sexual intercourse with infected person. Haemophilia is an X-linked genetic disorder of blood, It is not transmitted via any sexual practice. Genital herpes is an STD while sickle-cell anaemia is an autosomal hereditary disorder. The chances of a 5 years old boy contacting an STD are very rare since he is unlikely to have sex at this age. So, the correct answer is 'The chances of a 5-years boy contracting a STD are very rare'.

The smear of herpes virus is stained blue with

biology world of microbes cancer and aids hiv and aids immunity related disorders and problems

  1. 1% methylene blue

  2. 1% alcian blue

  3. 1% toluidine blue

  4. 1% coomassie blue

Show answer
Correct Option: C
Explanation:
  • Fluid or tissue scrap taken from the lesions and sores that appear in early stages of disease are used to diagnose if the patient is infected with viral infection or not.
  • The stains used are such that it may stain the acidic genetic material present in the rapidly dividing cells of the virus or bacteria
  • Since the fluid that is taken from the early lesions that appear on the skin in the early stage of the disease have syncytial condition ie more amount of genetic material is present therefore the staining will take place properly.
  • 1% toluidine blue is basic dye that will stain the nucleic acid blue.
  • Methylene blue is used to observe microscopic life under the microscope. It usually stains the outer wall or membrane of the organism.
  • Alcian blue is used to stain acidic polysaccharide in muscles and tissue in histological studies.
  • Coomassie blue is used for studying proteins as it stains the protein band blue color so that it can be observed as blue bands with a clear background as it does not stain any other thing in cell.
  • Therefore the option C is correct as toluidine is the only dye her which will stain the acidic genetic material in the dividing cells of the virus.
  • So, the correct answer is '1% toluidine blue'

To avoid transmission of STDs we should
(i) Avoid sex with multiple partners
(ii) Always have unprotected sex
(iii) Use condoms during coitus
(iv) Avoid sex with unknown partners
(v) Avoid sharing of needles

biology world of microbes cancer and aids hiv and aids immunity related disorders and problems

  1. (i), (ii), (iii), (iv) and (v)

  2. (i), (iii), (iv) and (v)

  3. (i), (ii) and (iii)

  4. (i), (ii) and (iv)

Show answer
Correct Option: B
Explanation:

STD's are the sexually transmitted disease that can be transferred from one organism to another by the exchange of body fluids.

For the prevention of STD one should avoid sex with multiple partners, always have protected sex and use condoms.
One should avoid having sex with unknown partners. 
Avoid sharing used needles as it is seen in the case of many hospitals and drug addicts.
So, the correct option is '(i), (iii), (iv) and (v)'

Which of the following is true regarding how increasing population helps in depletion of water table?

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  1. Increasing population creates demand for construction of houses, shops, offices, roads and pavements.

  2. This decreases the open areas like parks, and playgrounds.

  3. This, in turn, decreases the seepage of rainwater into the ground.

  4. All of the above

Show answer
Correct Option: D
Explanation:

All of the following are true. Increasing population creates demand for construction of houses, shops, offices, roads and pavements. This decreases the open areas like parks, and playgrounds. This, in turn, decreases the seepage of rainwater into the ground.

Water used by most of the industries is drawn from _________.

depletion of water table water a precious resource biology

  1. the ground

  2. the ocean

  3. ice caps

  4. All of the above

Show answer
Correct Option: A
Explanation:

Water used by most of the industries is drawn from the ground.

Water table may go down if the water is not sufficiently replenished. This may happen due to which of the following reason/(s)?

depletion of water table water a precious resource biology

  1. Increasing population

  2. Increasing industries

  3. Agricultural activities

  4. All of the above

Show answer
Correct Option: D
Explanation:

Water table may go down if the water is not sufficiently replenished. This may happen due to the following reasons. Increasing population, Increasing industries, agricultural activities.

Groundwater table may go down if the water is not sufficiently replenished. This may happen due to which of the following reason/(s)?

depletion of water table water a precious resource biology

  1. Scanty rainfall

  2. Deforestation

  3. Decrease in the effective area for seepage of water

  4. All of the above

Show answer
Correct Option: D
Explanation:

Water table may go down if the water is not sufficiently replenished. This may happen due to scanty rainfall, deforestation  and  decrease in the effective area for seepage of water.

How increasing population is responsible for water crises?

depletion of water table water a precious resource biology

  1. Increasing population creates demand for construction of houses this, in turn, decreases the seepage of rainwater into the ground.

  2. Increasing population creates demand for construction of houses this, in turn, increases the seepage of rainwater into the ground.

  3. both A and B

  4. none of these

Show answer
Correct Option: A
Explanation:

Increasing population creates demand for construction of houses this, in turn, decreases the seepage of rainwater into the ground. 

A majority of farmers in India depend upon _____ for irrigating their crops.

depletion of water table water a precious resource biology

  1. rains

  2. oceans

  3. both of the above

  4. none of the above

Show answer
Correct Option: A
Explanation:

A majority of farmers in India depend upon rains for irrigating their crops.

Water consumption in a city depends on

depletion of water table water a precious resource biology

  1. Size of the city.

  2. Population of the city.

  3. Demand of water.

  4. All of the above.

Show answer
Correct Option: D
Explanation:

Water consumption of a city depends on the size of the city which is directly related to the population of the city and demand of water in the city. When population increases consumption of water in daily needs, like drinking, bathing cooking also increases. Similerly construction work increase which consume excess amount of water.