Question

In order to ‘tap’ a maple tree for sap, how far should you insert the tap
(a) It must go no further than the bark and primary epidermis layer
(b) it must go into this year’s xylem
(c) it must go into this year’s phloem
(d) it must go into the pith
(e) it must go into the vascular cambium

The oldest tissues in a woody dicot stem are…
(a) The primary xylem and primary phloem
(b) The layer of xylem and phloem closest to the vascular cambium
(c) The ring nearest the cork cambium
(d) The ring of phloem just under the bark of the tree and the xylem closest to the cent

Growth rings in trees are caused by…
(a) the fact that the xylem does not grow at the same rate all year
(b) chromoplast pigments being released at the end of a growing season
(c) the phloem cells depositing large amounts of sugar at the start of a growing season
(d) the fact that vascular cambium dies at the end of every season
(e) cortex cells shrinking during the winter season

Answer 1

(#3) different temperatures and water availability. when water is scarce the tree grows many new small diameter pipes (xylem) which look darker to us and when water is plentiful the new xylem are few and bigger in diameter appearing lighter in color. if you cut a tree that grows in a tropical region which doesn't have the above mentioned variations you wont see any growth rings.

Answer 2

So, which one is it o.o a,b,c,d,e