Biological Classification MCQs for NEET — Botany Questions with Answers

None of the groups i.e., algae, fungi or mosses are purely anaerobic. Algae- The group algae includes most primitive plants with simple thalloid body. They are chlorophyll bearing photosynthetic aerobes.

Fungi- Generally aerobic but some unicellular forms like yeast can respire anaerobically (fermentation) which are beneficial and used in many industries for production of various products such as alcohol, enzymes, bread, etc.

Mosse- Includes simplest and primitive land plants which occupy a position between algae and pteridophyta.

A virus is a small particle that infects cells in biological organisms. Viruses are obligate intracellular parasites; they can reproduce only by invading and taking over othe cells as they lack the cellular machinery for self reproduction.

Viral envelope is a loose membranous covering that occurs in some animal viruses, rarely plant and bacterial viruses. In contrast to enveloped viruses, the viruses without an envelope are called naked. Envelope consists of proteins from (virus), lipids and carbohydrates (from host). It has subunits called peplomeres. Surface of envelope can be smooth or have outgrowths called spikes. Common enveloped viruses are HIV, herpes virus, vaccinia virus, etc.

Hepatitis B virus (HBV) is a DNA-containing double-shelled virus. It belongs to the Hepadnaviridae family and is a major cause of chronic liver disease and hepatocellular carcinoma worldwide.

In prokaryotes, chromatophores are internal membrane systems that may become extensive and complex in photosynthetic bacteria. They contain pigments like chlorophyll and carotenoids, and are involved in photosynthesis.

Under continuous supply of food and space in the laboratory conditions the bacterial population grows exponentially and shows a J-shaped curve, thus the curve would be hyperbolic.

Such populations ultimately crash when the population size grows beyond carrying capacity.

Tobacco mosaic virus (TMV) is a single-stranded RNA virus that infects plants, especially tobacco and other members of the family Solanaceae. Its genetic material is a single-stranded, positive-sense RNA molecule.

All statements are true except II.

Conjugation is process of transfer of genetic material that involve cell to cell connection. It was first reported in E. coli by Tatum and Lederberg in 1946. Transduction is a process of transfer of DNA by bacteriophage virus in bacteria. It was first reported in the Salmonella by Zinder and Lederberg in 1952. Gram staining is based on the composition or size of bacterial cell wall as gram +ve bacteria has thick cell wall compare to gram –ve bacteria.

Total number of bacteria produced = 2ⁿ

$n=\frac{\mathrm{Total} \mathrm{time}}{\mathrm{Time} \mathrm{of} \mathrm{division}}=\frac{175}{35}=5$

Thus, after 5 divisions total number of bacteria will 2⁵ = 32. Initially there are 10⁵ bacteria/mL and therefore, after 175 minutes, the concentration of bacterial cell will be 32 × 10⁵ or 3.2 × 10⁶ cells/mL.

In the fungus Agaricus, dikaryotisation (n + n) is brought about by two processes: clamp connections and somatogamy between two hyphae of different strains. Clamp connections allow the transfer of nuclei between adjacent cells, while somatogamy involves the fusion of two compatible hyphae.