Ag Crop Physiology Final Exam 2022 with complete solution

Ag Crop Physiology Final Exam 2022 with complete solution Define a plant hormone -Ans>>a plant hormone is an organic compound that is synthesized in one part of the plant and translocated to another part, and in low concentrations it will cause a physiological response List the three primary groups of secondary metabolites and describe their chemical difference. -Ans>>-terpenes -phenolics -nitrogen- containing compounds What type of experiment did scientists conduct using Arabidopsis to help identify "floral identity genes" in flowering plants? -Ans>>They used and ABC model, using petals, sepals, stamen and carpel. They used mutations and measured the plants using this model If the soil is at field capacity(Yp=0) and the root hairs have a Yw= -0.3 and a Yp= 0.2, what is the Ys? -Ans>>-0.5 If salt water intrusion should occur and the soil is still at field capacity and the Ys of the soil = -3.0, the Yw of the root hairs becomes -1.1. This is caused by a ________________ pressure potential. -Ans>>lower This was a direct effect of water moving _____________ the root hair cells. -Ans>>out of The process by which this water movement and change in water potential occurred is called __________? -Ans>>diffusion This plant growth regulator is a relatively new hormone called ________? - Ans>>Brassinosteroids Their effect on plant growth is similar to_____? -Ans>>Auxins However they may stimulate ______________ production causing lateral root formation. -Ans>>Ethylene Although this growth hormone has been found to increase the yield of many crops, the response depended on the __________ under which the crop was grown. -Ans>>stress Abscisic acid is translocated in the vascular cambium, primarily in the _________. - Ans>>phloem During water stress the pH of xylem sap ______ favoring dissociated ABA. - Ans>>increases This result in redistribution of ABA in the leaf and thus increases ABA reaching the guard cells stimulating closing of the guard cells by potassium ____________. - Ans>>effux ABA inhibits ethylene production promoting root growth when the water potential is ____________. -Ans>>low _________ is the major site of free cytokinin synthesis. -Ans>>root apical meristem Cytokinins move from through the xylem into the ___________ -Ans>>shoot Cytokinins induce cell division in callus cells in the presence of _______________. - Ans>>Auxin Cytokinins promote ___________ formation leading to organogenesis in tissue culture. - Ans>>callus The rate limiting step for ethylene production is ___________ induced by wounding of the plant. -Ans>>ACC synthase ____________ inhibits ethylene synthesis by blocking ACC oxidase and used to prevent ripening of fruits in storage. -Ans>>carbon dioxide These types of fruit produce ethylene and can be stimulated to ripen by ethylene. _____________ -Ans>>Climacteric Ethylene can be used to help _________ fruits such as pineapples. -Ans>>ripen The most predominant auxin that stimulates elongation and promotes cell division is __________ -Ans>>indoleacetic acid A synthetic auxin that is used as a herbicide is called _________ -Ans>>2, 4-D Most auxins are synthesized from _________ by removal of the amino acid group and terminal carboxyl group. -Ans>>tryptophan auxins can be synthesized in __________. -Ans>>shoot meristems Auxins are primarily transported through the __________. -Ans>>phloem Meristem identify genes -Ans>>flower initiation floral organ identity genes -Ans>>control formation of floral organs Cadastral genes -Ans>>spatial regulators of floral parts Rhythemic behaviors in plants are controlled by an endogenous oscillator or clock mechanism that contains physiological functions such as leaf movement, photosynthesis and etc. and is called the _________. -Ans>>circadian rhythm this clock enables organisms to determine the time of day or night at which a particular molecular or biochemical event occurs or seasonal response such as __________. - Ans>>photoperiod The duration of light that elicits a flowering response is called _____________. - Ans>>critical day length ________ is the primary light receptor molecule. -Ans>>phytochrome There are _____ forms of this molecule that determines the flowering response. - Ans>>two A short day plant flowers only in short days which is _________ than the critical day length or ________ than the critical night length. -Ans>>shorter, longer Addition of electrons or H's or removal of O2 -Ans>>reductase hydrolyze starch -Ans>>amylase Breaks bonds by the addition of H2O -Ans>>hydrolase The enzyme polypeptide chain is coiled and twisted and the shape is dependent on the ________- -Ans>>amino acids The place where the reaction occurs on the enzyme is specific and is called the _________. -Ans>>active site The _________ is when the enzyme has an active site that can be altered. - Ans>>induced-fit hypothesis Enzymes lower the energy of activation when they combine with a substrate to form the ____ -Ans>>enzyme substrate complex Mycorrhizae are _____ that colonize roots in a symbiotic relationship. -Ans>>fungi Mycorrhizae are composed of fine, tubular filaments called _________ which form th