Wood Lab Flashcards
what is responsible for secondary growth in plants?
2 secondary meristems
which 2 secondary meristems control secondary growth?
- vascular cambium
2. cork cambium
what is another name for the cork cambium?
phellogen
what is produced by the vascular cambium?
secondary xylem to the inside, secondary phloem to the outside
as a tree ages, what happens to the primary xylem and phloem?
xylem ceases to function and phloem is stretched and destroyed
the bulk of a tree is composed of what?
non-functional xylem
what replaces the epidermis in woody plants?
periderm
what is the function of the periderm?
outer protective layer
from whence is the periderm derived?
cork cambium
what does the periderm consist of?
phelloderm cork cambium cork (phellem)
what does bark consist of?
periderm and secondary phloem
what plant groups can have secondary growth?
gymnosperms and woody dicot angiosperms
what plant groups are hardwoods?
angiosperms
what plant groups are softwoods?
gymnosperms
at a cellular level, what is contained in hardwoods?
- parenchyma
- sclerenchyma
- tracheids
- vessels