The secondary xylem is produced more because
(1)cambium is more active towards the inner side
(2)cambium is more active towards the outer side
(3)xylem is more important than phloem
(4)All of the above
The primary and secondary phloems get gradually crushed because of
(1) continuous formation and accumulation of secondary xylem
(2)discontinuous formation and accumulation of secondary xylem
(3)by pressure of secondary xylem as they are continuously formed
(4)Both A and C
Primary xylem remains less or more intact towards the __________
(1) around the centre
(2) around the periphery
(3)outer to the pith
(4)Both A and C
Which one is correct for spring wood
(1)It is formed due more activity of cambium
(2)It produces more xylary elements having vessels with wider cavities
(3)It is also called as early wood
(4)All of the above
Which one is correct for autumn wood
(1)It is formed due less activity of cambium
(2)It produces fewer xylary elements having narrow vessels
(3)It is also called as late wood
(4)All of the above
The early wood is ___________ in color and late wood is ____________ in color.
(1)lighter, darker
(2)darker, lighter
(3)lighter, lighter
(4)darker, darker
The early wood has ___________ density and late wood has ____________ density.
(1)lower, higher
(2)higher, lower
(3)lower, lower
(4)higher, higher
Which one is true for annual ring
(1) A ring of autumn wood and a ring of spring wood constitute annual ring
(2) It appears as alternate concentric ring
(3)It gives an estimate of the age of the tree.
(4)All of the above
Heartwood is
(1)dark brown in color
(2)contains organic compounds like tannin, resins, gums, oils
(3)known as duramen
(4)All of these
How many of the statements are true for heartwood
a. It provides mechanical support to the stem
b. It does not conduct water
c. It is hard, durable and resistant to the attacks of microbes
d. It is the innermost layer of the wood
e. It comprises dead elements with highly lignified walls
f. More the heartwood is present the better is the quality of the wood
(1)4
(2)5
(3)6
(4)3