All Free Biology MCQs with Answers

2781. Which one of the following is wood rotting fungi:

• A. Bracket fungi or shelf fungi
• B. Truffles or morels
• C. Mushrooms or truffles
• D. Black bread mold or pink bread mold

Explanation: Answer is "Bracket fungi or shelf fungi"Wood rotting fungi destroy not only living trees but also structural timber. Bracket fungi/shelf fungi cause lot of damage to stored cut lumber as well as stands of tumber of living trees.These types of fungi are commonly associated with wood rotting and can be found growing on tree trunks or dead wood. The other options are not typically known as wood rotting fungi.

2782. Who used the term bacteriophage for the first time?

• A. Twort
• B. D'Herelle
• C. Louis Pasteur
• D. Charles chamberland

Explanation: Answer is "D' Herelle"Explanation: As far as discovery is conserned, Towrt discovered the bacterial viruses earlier than D'Herelle, however the term bacteriophage was used by D'Herelle for the first time. Bacteriophage means bacteria eater.Félix d'Herelle is credited with coining the term "bacteriophage" to describe viruses that infect bacteria.

2783. In Charles Chamberland's experiment one of the following represented filterable viruses:

• A. Bacteria
• B. Rabies virus
• C. TMV
• D. HIV

Explanation: Answer is "Rabies virus"Explanation: Those days word virus was generally used for any poisonous fluid which caused any disease or death. That is why Chamberland used the term filterable viruses for rabies causing agents as they passed through the filter.

2784. The virus that was first ever obtained in purified form was:

• A. TMV
• B. Pox virus
• C. Rabies virus
• D. Polio virus

Explanation: Answer is "TMV"Explanation: TMV was crystallized by W. M Stanley.

2785. The size of the largest virus is:

• A. 250 nm
• B. 20 nm
• C. 150 nm
• D. 200 nm

Explanation: Answer is "200nm"Explanation: Pox virus is the largest virus with 200 nm size.

2786. The transmittable nature of TMV was first observed by:

• A. W.M Stanley
• B. Ivanowsky
• C. Chamberland
• D. Twort

Explanation: Answer is "Ivanowsky"Explanation: Ivanowsky took bacteria free extract from infected tobacco leaves and sprinkled it over healthy plants which suffered from TMV later on.

2787. The protein subunits that make the protein coat of viruses are called:

• A. Capsids
• B. Capsomeres
• C. Monomers
• D. Amino acids

Explanation: Answer is "Capsomeres"Explanation: Capsomeres are those protein subunits whereas capsid is entire protein coat.

2788. The capsid of herpes virus and that of adenovirus differ from each other concerning:

• A. Chemical nature
• B. Type of subunits
• C. Number of subunits
• D. Role in the life cycle

Explanation: Answer is "Number of subunits"Explanation: Herpes virus have 162 capsomeres, whereas adenovirus have 252 capsomeres. Net difference is that of 90 capsomeres.

2789. How many additional capsomeres are found in adenovirus, as compared to those in herpes virus:

• A. 70
• B. 80
• C. 90
• D. 100

Explanation: Answer is "90"Explanation: Herpes virus have 162 capsomeres, whereas adenovirus have 252 capsomeres. Net difference is that of 90 capsomeres

2790. Which one of the following characters does not belong to fungi?

• A. Absorptive heterotrophic mode
• B. Eukaryotic organization
• C. Centrioles present
• D. Nuclear mitosis

Explanation: Answer is "Centriole present"Explanation: Fungi like plants lack centrioles.