Heartwood differs from sapwood in
presence of rays and fibres
absence of vessels and parenchyma
having dead and nonconducting elements
being susceptible to pests and pathogens.
In a dicotyledonous stem, the sequence of tissues from the outside to the inside is
Velamen is needed for
$I.$ Sunflower seed
$II.$ A wheat leaf
$III.$ Pea plant
$IV.$ Leaf blade of grass
Bulliform cells are present in which of the above plants?