Plant Pathology - Study Mode
[#456] Chlorophyll b is
Correct Answer
(B) C 55 H 70 O 6 N 4 Mg
Explanation
Solution: Chlorophyll b is C 55 H 70 O 6 N 4 Mg. Chlorophyll b is a form of chlorophyll. Chlorophyll b helps in photosynthesis by absorbing light energy. Its color is green, and it primarily absorbs blue light. The Chlorophyll b biosynthetic pathway utilizes a variety of enzymes. The axial ligands attached to the Mg 2+ center are often omitted for clarity. Appended to the chlorin ring are various side chains, usually including a long phytyl chain (C 20 H 39 O).
[#457] Viruses contain
Correct Answer
(D) Either RNA or DNA, never both
Explanation
Solution: Viruses contain Either RNA or DNA, never both. The essential components of infectious viral particles are nucleic acid (the genome) and protein. The genetic material (typically single-stranded RNA, but single-stranded DNA in some cases) is bound into the protein helix by interactions between the negatively charged nucleic acid and positive charges on the protein.
[#458] Teichoic acid found in
Correct Answer
(B) Gram (+) bacteria
Explanation
Solution: Teichoic acid is found in Gram (+) bacteria. Teichoic acids are bacterial copolymers of glycerol phosphate or ribitol phosphate and carbohydrates linked via phosphodiester bonds. These are found within the cell wall of Gram-positive bacteria such as species in the genera Staphylococcus, Streptococcus, Bacillus, Clostridium, Corynebacterium, and Listeria, and appear to extend to the surface of the peptidoglycan layer. Teichoic acids that are anchored to the lipid membrane are referred to as lipoteichoic acids (LTAs), whereas teichoic acids that are covalently bound to peptidoglycan are referred to as wall teichoic acids (WTA).
[#459] Which of the following pair has haploid structures?
Correct Answer
(B) Antipodal cells and egg cell
Explanation
Solution: Antipodal cells and egg cell has haploid structures. Egg cells and antipodal cells have a haploid number of chromosomes. In angiosperms, a single diploid megaspore mother cell matures within an ovule. Through meiosis. It gives rise to four megaspores (haploid).
[#460] The toxicity of zinc in soil is reduced by adding
Correct Answer
(A) superphosphate
Explanation
Solution: The toxicity of zinc in the soil is reduced by adding superphosphate. Superphosphate is a component of fertilizer that primarily consists of monocalcium phosphate, Ca(H 2 PO 4 ) 2 . Superphosphate or Super provides calcium, phosphorus and sulphur to promote legume growth and increase nitrogen fixation symbiotically from the atmosphere. Phosphorus inhibits the availability of zinc for absorption in soil, thus, zinc toxicity is reduced by adding superphosphate.