Give differences : Heartwood and Sapwood
Heartwood | Sapwood |
$(1)$ In old trees where secondary growth takes place in sufficient amount, that region is called Heartwood. | $(1)$ The outer region of secondary wood that possesses young xylem cells, such region is called sapwood. |
$(2)$ Its cells are filled with Tanin, Resin and other substances. |
$(2)$ It has living cells, tubes and fibres. |
$(3)$It is durable and has black colour | $(3)$ It is soft and of yellow colour. |
$(4)$ It gives mechanical strength. | $(4)$ It does physiological processes of plant. |
$(5)$ It loses the property of water transport. | $(5)$ It transports water and nutrients and stores food. |
In a stem which is covered by periderm and in which stomata are absent, gaseous exchange takes place through
Vascular cambium of dicot root is purely secondary in origin and arise from
The youngest layer of secondary xylem in the wood of dicot plant is located
Which one of the following is not a lateral meristem?
$I.$ Protection of internal tissues
$II.$ Protection of leaves from microbes
$III.$ Gaseous exchange
$IV.$ Reduction in the rate of transpiration through epidermal cells due to trichomes
Which of the function of epidermis is/are relevant from the above given statements?