Free Biodiversity and Variety of Life MCQs with Answers

291. Tumor causing virus:

• A. DNA enveloped
• B. DNA non-enveloped
• C. RNA enveloped
• D. RNA non-enveloped

Explanation: The correct answer is C) RNA enveloped, as some RNA enveloped viruses, particularly retroviruses like HTLV-1, are known to cause tumors in animals and humans.

292. Which of the following are the smallest bacteria?

• A. E. coli
• B. Mycoplasma
• C. Spirochete
• D. Streptococci

Explanation: The correct answer is B) Mycoplasma, as they are among the smallest known bacteria due to the absence of a cell wall, which contributes to their smaller size compared to other bacteria.

293. Plasma membrane and everything in it is called:

• A. Leucoplast
• B. Phragmoplast
• C. Protoplast
• D. Cytoplasm

Explanation: The correct answer is C) Protoplast, as it refers to the living part of the cell, including the plasma membrane and everything in it.

294. Hepatitis A and E are transrnitted by contact with _ from infected individuals.

• A. Scrum
• B. Blood
• C. Faeces
• D. Saliva

Explanation: The correct answer is C) Faeces, as Hepatitis A and E are primarily transmitted through contact with fecal matter from infected individuals.

295. Viruses can infect and parasitize _.

• A. Mammals
• B. Humans
• C. Bacteria
• D. All of these

Explanation: The correct answer is D) All of these, as viruses can infect and parasitize mammals, humans, bacteria, and various other hosts.

296. Which one is not a living character of the virus?

• A. Mutation
• B. Genome
• C. Replication
• D. Crystallization

Explanation: The correct answer is D) Crystallization, as it is not a living characteristic of the virus

297. Stanley crystallized:

• A. HIV
• B. TMV
• C. HBV
• D. T2

Explanation: Based on the information provided in the options, the correct answer is B) TMV, as Wendell Stanley is associated with crystallizing the tobacco mosaic virus.

298. Phage attaches to bacterial cell surface by its:

• A. Sheath
• B. Core
• C. Head
• D. Tail

Explanation: The correct answer is D) Tail, as the tail of the bacteriophage is responsible for attaching to the bacterial cell surface.

299. Which process/es take/s place during the lytic cycle?

• A. Replication
• B. Transcription
• C. Translation
• D. All of these

Explanation: The correct answer is D) All of these, as replication, transcription, and translation all take place during the lytic cycle of viral infection.

300. Pick the false statement about AIDS:

• A. HIV infection
• B. Reverse transcription in HIV particle
• C. Destruction of T cells
• D. Cure after proper medication

Explanation: The false statement is D) Cure after proper medication, as there is currently no cure for HIV/AIDS. While antiretroviral therapy (ART) can control the infection, it does not provide a cure.