All Free Biology MCQs with Answers

2791. The body of a fungus is called:

• A. Hypha
• B. Mycelium
• C. Fruiting body
• D. Coenocyte

Explanation: Answer is "Mycelium"Explanation: The body of fungus, called mycelium, consists of long, slender, branched tubular thread like filaments called the hyphae.

2792. Non-hyphal unicellular fungi are called:

• A. Yeast
• B. Mushrooms
• C. Toadstools
• D. Fruiting bodies

Explanation: Option a) Yeast: Correct! Non-hyphal unicellular fungi are called yeast. Option b) Mushrooms: Mushrooms are macroscopic fruiting bodies, not non-hyphal unicellular fungi. Option c) Toadstools: Toadstools are also macroscopic fruiting bodies, not non-hyphal unicellular fungi. Option d) Fruiting bodies: "Fruiting bodies" is a general term for reproductive structures of fungi, not non-hyphal unicellular fungi. Answer is "Yeast"Explanation: Yeast are non-hyphal unicellular fungi.

2793. The only exception concerning sexual reproduction in fungi is that of:

• A. Conjugation fungi
• B. Imperfect fungi
• C. Sac fungi
• D. Club fungi

Explanation: Option a) Conjugation fungi: Not the exception, as they undergo sexual reproduction by forming zygospores. Option b) Imperfect fungi: The exception, as they lack a known sexual reproductive stage. Option c) Sac fungi: Not the exception, as they undergo sexual reproduction by forming asci and ascospores. Option d) Club fungi: Not the exception, as they undergo sexual reproduction by forming basidia and basidiospores. Answer is "Imperfect fungi"Explanation: Perfect stage is sexual stage which is absent in Deuteromycota. That is why it is called imperfect fungi or fungi imperfecti.

2794. Conidia are also called as:

• A. Naked spores
• B. Zygospores
• C. Zoospores
• D. Sexual spores

Explanation: Answer is "Naked spores"Explanation: Conidia being produced on conidrophore, without any covering like sporangial wall are called naked spores. These are haploid and asexual spores.

2795. Heterokaryotic hyphae/cell contains:

• A. Two nuclei of same types
• B. Two nuclei of different types
• C. Many nuclei of same types
• D. Many nuclei of different types

Explanation: Option a) Two nuclei of the same types: Not typical of heterokaryotic hyphae/cells. Option b) Two nuclei of different types: Correct! Heterokaryotic hyphae/cells contain two or more genetically distinct nuclei. Option c) Many nuclei of the same types: Typical of dikaryotic states in some fungi, not heterokaryotic hyphae/cells. Option d) Many nuclei of different types: Not typical of heterokaryotic hyphae/cells. Answer is "Two nuclei of different types"Explanation: Heterokaryotic hyphae/cells also called dikaryotic hyphae/cells contain two nuclei of different genetic types or mating types.

2796. The word virus was generally referred to as a poison associated with disease and death at the time of:

• A. Louis Pasteur and Charles Chamberland
• B. Louis Pasteur and Ivanowsky
• C. Louis Pasteur and W.M Stanley
• D. Louis Pasteur and Robert Koch

Explanation: Answer is "Louis Pasteur and Robert Koch"Explanation: as microscopic techniques were not well developed at the time of Louis Pasteur and Robert Koch, the study about virus was very limited and the only thing that is known about it was that it is a poison associated with disease and death.

2797. A particle of nucleic acid wrapped in a protein coat is recognized as a:

• A. Cell
• B. Bacterium
• C. Virus
• D. Prion

Explanation: Answer is "Virus"Explanation: Viruses are actually particles of nucleoproteins i.e. a nucleic acid core (DNA or RNA) have been coated in a protein coat called capsid.

2798. The study of nucleocapsids is carried out in:

• A. Microbiology
• B. Mycology
• C. Virology
• D. Cell biology

Explanation: Answer is "Virology"Explanation: That branch of biology which deals with the study of viruses is called virology and as structurally viruses are nucleocapsids so it may be study of nucleocapsids as well.

2799. For the synthesis of their proteins, a virus uses:

• A. Its own metabolism
• B. Metabolism of its host organism
• C. Metabolism of its host cell
• D. None of these

Explanation: Answer is "Metabolism of its host cell"Explanation: Viruses are acellular entities having no cellular/metabolic machinery. Thus they have to rely upon the biosynthetic machinery of host for this purpose.

2800. Which one of the following organisms can pass through the porcelain filter?

• A. Virus
• B. Bacteria
• C. Fungi
• D. Protozoans

Explanation: Answer is "Virus"Explanation: Viruses having smaller size as compared to bacteria can pass through the porcelain filter and it was first proved by Charles Chamberland by filtering rabies virus through porcelain filter.