phloem
Noun
Meaning
That portion of fibrovascular bundles which corresponds to the inner bark; the liber tissue; -- distinguished from xylem.
Source: Webster's dictionarySynonyms
Hypernyms
Phrases with the word
Examples
Apart from the xylem and phloem in their vascular bundles, leaves are composed mainly of parenchyma cells.
Diagram illustrating how Cuscuta uses haustoria to penetrate the vascular system of its host plant and remove sugars and nutrients from the host's phloem.
As a result, tissues beyond the secondary phloem including the epidermis and cortex, in many cases tend to be pushed outward and are eventually "sloughed off" (shed).
By the formation of a layer of cambium between the bundles (interfascicular cambium), a complete ring is formed, and a regular periodical increase in thickness results from the development of xylem on the inside and phloem on the outside.
Exceptions include highly lignified cells, the sclerenchyma and xylem which are dead at maturity, and the phloem sieve tubes which lack nuclei.
In plants with secondary growth, the vascular cambium, originating between the xylem and the phloem, forms a cylinder of tissue along the stem and root.