Plant Pathology - Study Mode

[#486] Tick out the wrong pair
Correct Answer

(D) Pandemic - Disease not prevalent throughout the country, continent or the world

Explanation

Solution: A. Endemic - Confined to a particular country, district, or location. A disease outbreak is endemic when it is consistently present but limited to a particular region. This makes the disease spread and rates predictable. B. Epidemic - The disease which appears very virulently among the people. The Centers for Disease Control and Prevention (CDC) describes an epidemic as an unexpected increase in the number of disease cases in a specific geographical area. Yellow fever, smallpox, measles, and polio are prime examples of epidemics. C. Epiphytotic - The diseases which occur widely periodically. When the number of individuals a disease affects increases dramatically, it is said to have become an epidemic (meaning "on or among people"). D. Pandemic - Disease not prevalent throughout the country, continent or the world. It is wrongly paired. A PANDEMIC is an epidemic that's spread over multiple countries or continents.

[#487] Chlorophylls absorb visible light of wavelengths
Correct Answer

(D) 400 - 500 nm only and 600 - 700 nm

Explanation

Solution: Chlorophylls absorb visible light of wavelengths ranging from 400 - 500 nm only and 600 - 700 nm. Chlorophyll is any of several related green pigments found in cyanobacteria and the chloroplasts of algae and plants. Chlorophylls absorb light most strongly in the blue portion of the electromagnetic spectrum as well as the red portion. Plant chlorophylls absorb mainly in blue (between 400 and 500 nm) and red (around 650 to 680 nm).

[#488] In a fertilized ovule, n, 2n and 3n conditions occur respectively in
Correct Answer

(B) Egg, nucellus and endosperm

Explanation

Solution: In a fertilized ovule, n, 2n and 3n conditions occur respectively in Egg, nucellus and endosperm. In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: the integument, forming its outer layer, the nucellus, and the female gametophyte in its center. In flowering plants, one sperm nucleus fuses with the egg cell to produce a zygote, and the other fuses with the two polar nuclei of the central cell to give rise to the polyploid (typically triploid) endosperm. This double fertilization is unique to flowering plants, although in some other groups the second sperm cell does fuse with another cell in the megagametophyte to produce a second embryo.

[#489] Who is regarded as father of Nematology?
Correct Answer

(B) NA Cobb

Explanation

Solution: NA Cobb is regarded as the father of Nematology. Nathan Augustus Cobb is known as "the father of nematology in the United States".
He provided the foundations for nematode taxonomy and described over 1000 different nematode species. An individual with a variety of skills, he made significant contributions to several scientific disciplines and the USDA Nematology.

[#490] Leaf smut of rice is caused by
Correct Answer

(A) Entyloma oryzae

Explanation

Solution: Leaf smut of rice is caused by Entyloma oryzae. Leaf smut, caused by the fungus Entyloma oryzae, is a widely distributed, but somewhat minor, disease of rice. The fungus produces slightly raised, angular, black spots (sori) on both sides of the leaves. This is a minor fungal disease in which small slightly raised black spots develop mostly on the leaves. Raised spots or pustules break open releasing air-borne spores.