secondary growth

What defines lateral meristem?

Lateral meristem is a cylindrical sheath of meristematic cells responsible for secondary growth that increases the girth of stems and roots.

What are the two types of lateral meristems?

Vascular cambium and cork cambium.

What is the function of the vascular cambium?

The vascular cambium produces secondary xylem (wood) and secondary phloem (bark).

What is the difference between wood and bark?

Wood is everything interior to the vascular cambium, and consists of xylem, while bark is everything exterior and consists of phloem and periderm.

Describe the difference between early wood and late wood.

Early wood (spring wood) has a high proportion of wide vessels; late wood (summer wood) has fewer, narrower vessels or thick-walled tracheids.

What are lenticels, and what is their function?

Lenticels are regions of rounded cork cells that allow for gas exchange in the bark.

What distinguishes conifer wood from angiosperm wood?

Conifer wood contains tracheids, whereas angiosperm wood has vessel elements and is generally more complex.

What do fusiform initials and ray initials produce in the vascular cambium?

Fusiform initials produce secondary xylem or phloem, while ray initials produce parenchyma cells that function in storage and metabolic support.

What is dendrochronology?

Dendrochronology is the study of growth rings in trees to understand historical climate activity.

Explain the role of cork cambium in the plant body.

Cork cambium arises from the pericycle, replacing the epidermis and producing cork cells to the exterior and phelloderm to the interior.