Study Set Content:
one year's growth of xylem
annual ring
tropical trees produce what kind of wood
ungrained and uniform wood
may contain many layers of xylem cells and it is all the layers produced in one growing season that constitute
an annual ring
vascular cambium produces more
secondary xylem than phloem
annual ring not just?
the dark layers
xylem cells characteristic
stronger more rigid walls and less subject to collapse from tension
what does annual rings indicate
age of the wood, climate, and conditions that happen during the tree's lifetime
fairly obvious lighter streaks or lines radiating out from the center across the annual rings when a tree trunk is transverse, or cross section.
vascular rays
In the early stages, primary tissues of stems of young herbaceous dicot, woody dicots, and cone-bearing trees are all arranged
in a similar fashion
function of vascular rays
lateral conduction of nutrients and water from stele, xylem and phloem, to the cortex, with some cells storing food
parenchyma cells of vascular rays may remain alive for
10 or more years
secondary xylem is aka
wood
alfalfa is aka
medicago
in woody plants
obvious differences begin to appear as soon as vascular and cork cambium develop
while the wood of woody dicot trees are called
hardwood
Pines and other cone-bearing trees have xylem that consists primarily of
tracheids
woods are softer than that of trees with them and is commonly referred to as
softwood
Pines and other cone-bearing barely have
fibers or vessel elements produced
extension through the phloem
Phloem ray
protrusion due to the expansion of the protoplasm that leads to the cavity of the vessel or tracheids that prevent further conduction of water and dissolved substance-resins, gums, and tannins begin to accumulate, along with pigments that darken the color of the wood
Tyloses
