Tag: world of virus

Questions Related to world of virus

Make correct pair

A. Cyanophyceae                      b. Green colour
B. Chlorophyceae                     a. Blue green colour
C. Phaeophyceae                      d. Red colour
D. Rhodophyceae                     c. Brown colour

  1. Aa, Bb, Cc, Dd

  2. Ab, Bc, Cd, Da

  3. Ab, Ba, Cd, Dc

  4. Ad, Bd, Ca, Db


Correct Option: A
Explanation:
(A) Cyanophyceae - the blue green color is because of pigments phycobilins and phycocyanin, in addition to chlorophyll pigments
(B) Chlorophyceae  -The green colour is due to presence of a chl -a chl - b xanthophylls and carotenes 
(C) Phaeophyceae _ Brown colour is due to presence of pigment  fucoxanthin in addition to chlorophyll pigments
(D) Rhodophyceae _ Colour is red due to presence of r - pigment (r_phycoerythin) in addition to chlorophyll pigments
So, the correct answer is 'Aa, Bb, Cc, Dd'

Which of the following is the reason behind the autotrophic nature of algae?

  1. It can carry out photosynthesis

  2. They depend on other animals for nutrition

  3. They are insectivores

  4. None of these


Correct Option: A
Explanation:

The answer is option A "It can carry out photosynthesis"
Because organisms that carry out photosynthesis to make their own food are called autotrophic. Algae contain chlorophyll pigments which helps them to trap energy from sunlight to form glucose (food) on their own.
While option B represents a feature of heterotrophs and option C for carnivores that eat insects.

Which of the following is a microscopic plant?

  1. Algae

  2. Fungi

  3. Bacteria

  4. None of the above


Correct Option: A
Explanation:

Algae are single-celled, aquatic, microscopic plants. As they can make their own food, they are considered as plants. They contain photosynthetic pigment, chlorophyll-like plants. However, they do not have root, leaves and stems, unlike plants.

Thus, the correct answer is 'Algae'.

The agents which are known to cause Creutzfeldt-Jakob disease (CJD) are 

  1. Protein particles

  2. A class of bacteria

  3. A class of viruses

  4. Fungi


Correct Option: A
Explanation:

Creutzfeldt-Jakob disease (CJD) is caused by infectious protein particle called prions.

Which gives the green colour appearance to the pond?

  1. Algae

  2. Grass

  3. Fertilizer

  4. None of the above


Correct Option: A
Explanation:
Planktonic Algae bloom can appear as a paint-like scum on top of the water's surface. The water column turns green throughout and is often described as "pea soup."

So, the correct answer is 'Algae'.

Viruses that infects plants generally have

  1. ds DNA

  2. ssRNA

  3. ds RNA

  4. ssDNA


Correct Option: B
Explanation:

  • Approximately around 70% of viruses infecting plant are ssRNA, 20% are ssDNA and rest are either dsRNA or dsDNA.
  • ssDNA is advantageous due to it's ability to infect and duplicate it's genome faster.

So, the correct option is 'ssRNA'.

Cryptogram of a virus (Gibbs and Harrison 1968) has $4$ pairs of symbols to be used in virus classification. The pair $1$ indicates

  1. Type of nucleic acid in virus/ structure of nucleic acid

  2. Molecular weight of nucleic acid/ percentage of nucleic acid

  3. Shape of virus particle/ shape of capsid

  4. Kind of host infected/ kind of vector


Correct Option: A
Explanation:
Cryptogram code is proposed by Gibbs and Harrison (1968) to describe the virus. The code consists of 4 pairs of symbols. 
The first pair indicates- The type of nucleic acid/number of strands in the particular nucleic acids. For example cryptogram of Poliovirus is written as R/l: 2.5/30: S/S: V/O.
So, the correct answer is option A, Type of nucleic acid in virus/ structure of nucleic acid

The latest view for the origin of viruses is?

  1. They have arisen from nucleic acid and proteins found in primitive soup

  2. They arose from bacteria as a result of the loss of the cell, ribosome etc

  3. They arose from some bacteria, which has developed a nucleus only

  4. They are modified plasmids, which are in-fact the fragments of the nucleic acids of host


Correct Option: A

Restriction endonuclease enzyme obtained from?

  1. Virus

  2. Bacteria

  3. Plant

  4. Fungi


Correct Option: A