from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The outer layers of tissue of woody roots and stems, consisting of the cork cambium and the tissues produced by it, such as cork.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The outer layer of plant tissue; the outer bark.
- n. The perisarc; the hard outer layer of hydroids and other marine animals.
from the GNU version of the Collaborative International Dictionary of English
- n. The outer layer of bark.
- n. The hard outer covering of hydroids and other marine animals; the perisarc.
from The Century Dictionary and Cyclopedia
- n. In zoology, epiderm or cuticle forming an investing sheath or tube, as in some tubularian hydromedusans; a kind of hard perisarc or cortical layer of the cœnosarc of certain hydrozoans.
- n. 2. In botany, the continuous layers of cork which cover the stems of many plants after they acquired a certain age.
Slide 4: The periderm (cork) • The periderm is the outer layer of the bark which replaces the epidermis and is formed by the cork cambium.
It may take the form of either epidermis or periderm.
Our culinary experience of periderm is usually limited to the skins of potatoes, beets, and so on.
In addition to some of the above, Indian reports include root periderm brown scorch, Pythium sp., radish mosaic virus, damping off, Rhizoctonia solani, and the seed-borne Alternaria alternata.
The cork periderm and the cortex below this form the exterior protection for the root.
To form the wound periderm certain metabolic processes are necessary These processes use energy which is gained by expiring starch stored in the tuber.
Increased temperature and humidity stimulate the yam tubers to from cork cells which can hermetically close the lesions The cork cells are formed in the cork cumbium and then make their way to the wound areas which they close with several layers of wound periderm (BAUTISTA, 1990)
The yam worm particularly damages the periderm and subperiderm, cell layers which are directly under the cork shell.
Immune suppressive properties of MUC16, along with its expression in ovarian cancer cells and fetal periderm, suggest a role for MUC16 in immune evasion of ovarian cancer cells from the host immune system and in fetal tolerance from maternal immune rejection during early pregnancy
Hardardottir H, Parmley TH 2nd, Quirk JG Jr, Sanders MM, Miller FC, et al. (1990) Distribution of CA125 in embryonic tissues and adult derivatives of the fetal periderm.