BIOLOGY
HORMONES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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It is the matching of the products of a plant’s R gene with the products of a pathogen’s Avr gene.
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It is the coiling of a plant around a rigid object.
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When an insect incorporates plant-produced canavanine instead of arginine, the insect dies.
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When an infection occurs at one site on a plant, hormones trigger a signal transduction pathway that leads to increased production of defensive chemicals by other parts of the plant.
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Detailed explanation-1: -Upon infection with necrotizing pathogens many plants develop an enhanced resistance to further pathogen attack also in the uninoculated organs. This type of enhanced resistance is referred to as systemic acquired resistance (SAR).
Detailed explanation-2: -Systemic acquired resistance (SAR) is a mechanism of induced defense that confers long-lasting protection against a broad spectrum of microorganisms. SAR requires the signal molecule salicylic acid (SA) and is associated with accumulation of pathogenesis-related proteins, which are thought to contribute to resistance.
Detailed explanation-3: -Salicylic acid (SA) is a critical plant hormone that regulates numerous aspects of plant growth and development as well as the activation of defenses against biotic and abiotic stress.
Detailed explanation-4: -The systemic acquired resistance response is dependent on the plant hormone, salicylic acid.