Tag: evs

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Questions Related to evs

Multiple choice evs light and shadow nature and sources of light how light travels path of light elementary ideas of astronomy

We can see an object from every direction due to ____________ of the incident light ray on the object.

  1. regular refraction

  2. regular reflection

  3. irregular reflection

  4. none of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Irregular reflection makes us see all the objects and everything around us. If light gets regularly reflected then every object would act like a mirror and our surroundings would be illuminated. This would have a blinding effect on eyes making it harder for us to see.

Multiple choice evs light and shadow nature and sources of light how light travels path of light elementary ideas of astronomy

A leaf which contains only green pigments, is illuminated by a laser light of wave length 0.6328 $\mu$ m. It wound appear to be:

  1. Brown

  2. Black

  3. Red

  4. Green
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

0.6328 $\mu m$ = $6328 \mathring A$
This is wavelength of red colour. So, this light will be absorbed by green pigments. 
The leaf will appear black.

Multiple choice evs mosquitoes and malaria diseases caused by mosquitoes contaminated water spreads disease water borne diseases mosquito and human health

The pathogen transmitted through female mosquito causing chronic inflammation of the lymphatic vessels of the lower limbs in man is__________

  1. Ascaris sp.

  2. E. histolytica

  3. Streptococcus pneumoniae

  4. W. malayi
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

W.malayi also called as brugia malayi are the important agents of bancroftian and brugian(it is sometimes referred to as Malayan)filariasis. In contrast to many other mosquito-borne infections of medical significance, lymphatic filariae are transmitted by not just one but by several genera of mosquitoes.

So, the correct option is 'W.malayi'.

Multiple choice evs mosquitoes and malaria diseases caused by mosquitoes contaminated water spreads disease water borne diseases mosquito and human health

The mouth parts of Anopheles are adapted to

  1. Biting and chewing type feeding

  2. Piercing and sucking type feeding

  3. Chewing type feeding

  4. Sucking type feeding
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 Female mosquito have mouthparts that pierce food items to enable sucking of internal fluids. In female mosquitoes, all mouthparts are elongated. The labium encloses all other mouthparts like a sheath. The labrum forms the main feeding tube, through which blood is sucked. Paired mandibles and maxillae are present, together forming the stylet, which is used to pierce an animal's skin. During piercing, the labium remains outside the food item's skin, folding away from the stylet. Saliva containing anticoagulants, is injected into the food item and blood sucked out, each through different tubes.

So, the correct option is B. ( Piercing and Sucking type )

Multiple choice evs mosquitoes and malaria diseases caused by mosquitoes contaminated water spreads disease water borne diseases mosquito and human health

Which state of Plasmodium is infective for mosquito?

  1. Sporozoite

  2. Ookinete

  3. Trophozoite

  4. Gametocyte
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The gametocytes are the sexual stages of Plasmodium that develop in human red blood cells. When a mosquito takes a blood meal, it ingests these gametocytes, making them the infective stage of the parasite for the mosquito vector.

Multiple choice evs mosquitoes and malaria diseases caused by mosquitoes contaminated water spreads disease water borne diseases mosquito and human health

The difference between Culex and Anopheles is

  1. Culex sits antiparallel to the substratum

  2. Anopheles sits at an angle to the substratum

  3. Anopheles sits parallel to the substartum

  4. Culex sits at an angle to the substratum
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Culex causes filariasis, bird malaria. Its body rests parallel to the surface or substratum. Whereas Anopheles causes malaria. The body is slender and rests at an angle to the surface or substratum.
Therefore, the correct answer is option B.

Multiple choice evs mosquitoes and malaria diseases caused by mosquitoes contaminated water spreads disease water borne diseases mosquito and human health

Spread of Malaria can be best controlled by ______________.

  1. Killing adult mosquito only.

  2. Proper medical treatment only.

  3. Making the mosquito breeding places unsuitable for completion of life-cycle.

  4. All of the above.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A malaria control method that targets mosquito larvae and pupae as they mature in standing water could be an important supplementary measure in the fight against the disease. Larval source management (LSM) is a method that targets immature mosquitoes, found in standing water before the females develop into flying adults that are capable of transmitting malaria. This is done by permanently removing standing water, for example by draining or filling land; making temporary changes to mosquito habitats to disrupt breeding, for example by clearing drains to make the water flow; or larviciding by adding chemicals or biological larvicides to standing water to kill larvae.