Plant Pathology - Study Mode

[#296] Ovule is straight with funiculus, embryo sac, chalaza and micropyle lying on one straight line. It is
Correct Answer

(A) Orthotropous

Explanation

Solution: The ovule is straight with funiculus, embryo sac, chalaza and micropyle lying on one straight line. It is Orthotropous. An orthotropous ovule is one in which no curvature takes place during development the micropyle is positioned opposite the funiculus base. In the orthotropous ovule the body of these ovules is straight so that the chalaza, where the nucellus and integuments merge, the funicle, which attaches the ovule to the placenta, and the micropyle are all aligned.

[#297] The wavelength of light most absorbed during photosynthesis is
Correct Answer

(B) 660 nm

Explanation

Solution: The wavelength of light most absorbed during photosynthesis is 660 nm. Not all wavelengths of light can support photosynthesis. The photosynthetic action spectrum depends on the type of accessory pigments present. For example, in green plants, the action spectrum resembles the absorption spectrum for chlorophylls and carotenoids with absorption peaks in violet-blue and red light. The non-absorbed part of the light spectrum is what gives photosynthetic organisms their colour and is the least effective for photosynthesis in the respective organisms.

[#298] The largest group of virus is
Correct Answer

(A) Closteroviridae

Explanation

Solution: The largest group of the virus is Closteroviridae. Closteroviridae is a family of viruses. Plants serve as natural hosts. Viruses in the family Closteroviridae are non-enveloped, with flexuous and filamentous geometries. The diameter is around 10 - 13 nm, with a length of 950 - 2200 nm. Genomes are linear and non-segmented, bipartite, and around 20kb in length. The family Closteroviridae contains more than 30 plant viruses with flexuous, filamentous virions, with either mono- or bipartite (one tripartite) single-stranded positive-sense RNA genomes.

[#299] Complete girdling ultimately kills the tree due to
Correct Answer

(A) Starvation of root

Explanation

Solution: Complete girdling ultimately kills the tree due to Starvation of roots. Girdling also called ring-barking, is the complete removal of the bark from around the entire circumference of either a branch or trunk of a woody plant. Girdling results in the death of the area above the girdle over time. Girdling results in the removal of the phloem, and death occurs from the inability of the leaves to transport sugars to the roots. In this process, the xylem is left untouched, and the tree can usually still temporarily transport water and minerals from the roots to the leaves.

[#300] In aerobic respiration one glucose produces
Correct Answer

(D) 10 NADH + 2 FADH 2 + 2 ATP + 2 GTP

Explanation

Solution: In aerobic respiration one glucose produces 10 NADH + 2 FADH 2 + 2 ATP + 2 GTP. Aerobic respiration requires oxygen (O 2 ) to create ATP. The potential of NADH and FADH 2 is converted to more ATP through an electron transport chain with oxygen and protons as the "terminal electron acceptors". In aerobic conditions, the process converts one molecule of glucose into two molecules of pyruvate (pyruvic acid), generating energy in the form of two net molecules of ATP.