Secondary Growth

Question 1

SECONDARY GROWTH

Answer 1

The increase in girth of a plants stem or root

Occurs due to activity of cambium

Question 2

FORMATION OF CAMBIUM RING

Answer 2

cambium division occurs extending out of vascular bundle

adjacent cambium strips fuse with one another to create a cambium ring

Question 3

CAMBIUM RING

Answer 3

Cambium continues to divide
new cells are form in the exterior and interior of the ring which turn into xy and ph
more activity in the interior creating more xy (forms main bulk of trees)

Question 4

ANNUAL RINGS

Answer 4

warmer weather = higher activity = bigger and wider xy

cooler weather = minimal activity = smaller narrow xy

Question 5

HEARTWOOD

Answer 5

Old mature trees xylem in the centre of the tree begins to to be filled with waste products e.g. resins
mechanical support

Question 6

SAPWOOD

Answer 6

Outer region of secondary wood
lighter in colour
conduction of water and minerals
mechanical support

Question 7

HARDWOOD

Answer 7

hardwood: refers to (wood derived from) angiosperms, i.e. those with true flowers,
eg: pukatea, beech, hinau, tawa, etc.
porous

Question 8

SOFTWOOD

Answer 8

softwood: refers to (wood derived from) gymnosperms, eg: kauri, kahikatea, totara,
rimu, matai, miro, etc.
Non-porous