STRUCTURAL ORGANISTION OF PLANTS AND ANIMALS
ANATOMY OF FLOWERING PLANTS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Uniform environmental conditions
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Non-uniform environmental conditions
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Absence of secondary growth
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Absence of primary growth
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Detailed explanation-1: -Annual rings are made out of a year’s worth of spring and fall wood. Annual rings are formed in trees due to non-uniform climatic conditions throughout the year. Cambium is very active in the spring season but in winter the activity reduces.
Detailed explanation-2: -Due to differential seasonal activity of cambium (during autumn and spring season) alternate light & dense wood is cut off leading to formation of annual rings.
Detailed explanation-3: -Annual rings and growth rings are formed due to fluctuation in the activity of cambium. Cambium is the meristematic layer responsible for cutting off vascular tissues – xylem and phloem. Initially, it is present in patches as a single layer between vascular bundles.
Detailed explanation-4: -growth ring, in a cross section of the stem of a woody plant, the increment of wood added during a single growth period. In temperate regions the growth period is usually one year, in which case the growth ring may be called an “annual ring.” In tropical regions, growth rings may not be discernible or are not annual.
Detailed explanation-5: -So, the correct answer is ‘Annual rings are not prominent in trees of temperate region’