Plant roots Is there a definate boundary between the root cap and the rest of th
ID: 82162 • Letter: P
Question
Plant roots
Is there a definate boundary between the root cap and the rest of the root?
Is there a boundary between the the region of cell division and cell elongation?
As the cell elongate, what position does the nucleus assume?
What is the appearance of the cytoplasm?
Plant Stems
Where in the stem tip does one begin to see differentiated tissues, such as xylem cell?
Is there a discrete zone of cell elongation in the step tip?
As the cells elongate, what position does the nucleus assume?
What is the appearance of the cytoplasm?
Comparing monocots and dicot stem tips, how are they similar and different?
Explanation / Answer
A clear distinct cell boundary exists in close meristem structure. A discrete region of meristem produces either the root cap cells or cap and epidermal cells. For example in Zea mays and Arabidopsis thaliana. In an open meristem structure like in Vicia faba, it is not well defined, the boundary is unstable. Cells between root cap and stellar pole divide to form unstable boundary between cap and the rest root.
Plant stem
The xylem appears in the zone of cellular maturation. Here the cells begin to deifferentiate and xylem cells are the first ones to develop.
Zone of cell division lies under and behind at the very tip of root cap.however there is no discrete zone of elongation in stem tip.
Comparison between dicot and monocot stem tips
Both monocots and dicot stems have epidermis made up of parenchyma cells and have a thick cuticle. Hypodermis in dicots is made up of collenchyma cells while that of monocot is sclerenchyma cells.