What is the cambium in tree structure?
The cambium is a microscopically thin layer of living cells with protoplasm in their cell cavities.
Cells whose axes is horizontal, they extend radially outward from the pith.
They are called Rays
Rays provide what?
Horizontal conduction of sap in the tree, some store carbohydrates.
Meristems or Meristematic Tissue
Tree cells that can divide to form new cells.
Apical Meristems
The growing tips of twigs, responsible for the elongation of trees. Pith cells are what’s left in the path traveled by them.
Where and how does thickening growth happen?
In the Cambium, lateral meristem. Through cell division.
Photosynthesis
Water from the soil is combined with carbon dioxide from the atmosphere, catalyzed by chlorophyll and energized by sunlight. Produces a basic sugar C6H12O6.
What is sap?
Sap carries the basic sugar, water plus other materials, to where the tree can use it to build new cells in the cambium layer.
When does a cambium cell form the secondary wall?
Once the daughter cells have attained their ultimate size and shape.
What is the secondary wall built from?
Mainly of cellulose, long-chain molecules that are strong and stable. Further fortified by lignin.
What cells are sometimes termed prosenchyma?
Cells who lose their protoplasm, function to support the tree and in some cases conduct sap.
Cells that retain their protoplasm in the sap wood are called?
Parenchyma
Where are parenchyma cells primarily found?
In the rays
What can parenchyma cells do?
They have protoplasm and can assimilate and store food.
Contrast within a single growth ring is termed?
Earlywood and latewood
Grain direction often defines what?
The direction of the dominant longitudinal cells in a tree
Uneven and even-grained refer to what?
The contract difference between the late and early wood
What is sapwood?
Wood portion involved in sap conduction
What materials forms in the cell walls during the transformation into heartwood?
Extractives p
When is sapwood transformed into heartwood?
In the center of the stem, nearest the pith, prosenchyma cells cease to conduct sap and the parenchyma cells die. The sapwood transforms into heartwood.
Transverse Plane
The end grain, looking down on the stump.
Radial Plane
Radiating lines, crossing through the pith
Tangential Plane
Parallel to the pith but not touching it. Tangent to growth rings.
Quartersawn
The growth rings form angles of anywhere from 60 to 90 degrees with the surface.
