HORTICULTURE SCIENCE
PLANT BIOLOGY
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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xylem production in winter
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a year of drought
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decreased production of phloem
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increased production of xylem
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Detailed explanation-1: -For example, tree rings usually grow wider in warm, wet years and they are thinner in years when it is cold and dry. If the tree has experienced stressful conditions, such as a drought, the tree might hardly grow at all in those years.
Detailed explanation-2: -Each year, the tree forms new cells, arranged in concentric circles called annual rings or annual growth rings. These annual rings show the amount of wood produced during one growing season. In Canada and the North United States, the growing season begins in the spring.
Detailed explanation-3: -A tree ring, representing one year, consists of two layers: A light colored layer which forms in the spring and early summer, which is typically thicker because the tree is growing. A dark colored layer which forms in late summer and fall, which is typically thinner because the trees growth slows.