Plant Pathology - Study Mode
[#251] Late blight of potato turned into an epidemic in which year?
Correct Answer
(A) 1845
Explanation
Solution: Late blight of potato turned into an epidemic in the year 1845. Phytophthora infestans is an oomycete or water mold, a fungus-like microorganism that causes the serious potato and tomato disease known as late blight or potato blight. The Irish Potato Famine, also known as the Great Hunger, began in 1845 when a mold known as Phytophthora infestans (or P. infestans) caused a destructive plant disease that spread rapidly throughout Ireland.
[#252] Path of dark reaction of photosynthesis was traced through the use of
Correct Answer
(B) 14 CO 2
Explanation
Solution: The path of the dark reaction of photosynthesis was traced through the use of 14 CO 2 . Calvin and his co-workers by using the isotope of C which is 14C to trace the path of the carbon fixation in light reaction. Due to his discovery, the cycle is known as the Calvin cycle (Dark reaction) which is the common path for all plants in photosynthesis.
[#253] Which one is product in respiration and reagent in photosynthesis
Correct Answer
(B) CO 2
Explanation
Solution: CO 2 is one product in respiration and a reagent in photosynthesis. Cellular respiration converts ingested nutrients in the form of glucose (C 6 H 12 O 6 ) and oxygen to energy in the form of adenosine triphosphate (ATP). CO 2 is produced as a byproduct of this reaction. During photosynthesis, plants take in carbon dioxide (CO 2 ) and water (H 2 O) from the air and soil. Within the plant cell, the water is oxidized, meaning it loses electrons, while the carbon dioxide is reduced, meaning it gains electrons.
[#254] A photosynthesising plant is releasing 18 O more than the normal. The plant must have been supplied with
Correct Answer
(B) H 2 O with 18 O
Explanation
Solution: A photosynthesizing plant is releasing 18 O more than normal. The plant must have been supplied with H 2 O with 18 O. Ruben, Hassid and Kamen (1941) using a heavy isotope of oxygen, ` 18 O` in water, found that oxygen evolved in photosynthesis comes from water evolution of oxygen does not require carbon dioxide.
[#255] Infection of smut of maize (Ustilago maydis) occurs during
Correct Answer
(A) Vegetative stage
Explanation
Solution: Infection of smut of maize (Ustilago maydis) occurs during the Vegetative stage. Corn smut is a plant disease caused by the pathogenic fungus Ustilago maydis that causes smut on maize and teosinte. The fungus forms galls on all above-ground parts of corn species. The fungus infects all parts of the host plant by invading the ovaries of its host. The infection causes the corn kernels to swell up into tumor-like galls, whose tissues, texture, and developmental patterns are vegetative and mushroom-like.