Dictionary > Metaxylem

Metaxylem

Definition
noun
The part of the primary xylem that is last to develop from the procambium, and characterized by weblike or pitted surfaces and broader tracheary elements than the protoxylem
Supplement
In vascular plants, the major conducting tissues are xylem and phloem. The xylem tissues may be classified as primary or secondary depending on where they are derived. The primary xylem is the type of xylem produced from the primary growth. It differentiates into two parts: (1) protoxylem and (2) metaxylem. The protoxylem is the first one to form followed by the metaxylem (thus, the name). Both protoxylem and metaxylem are found in the primary vascular bundle, and involved in the conduction of water and minerals towards the apical shoot. They are produced by the procambium. Both of them contain tracheids, vessels, and parenchyma. However, the metaxylem has more tracheary elements than the protoxylem. Furthermore, the lumen of tracheary elements of the metaxylem is larger than that of the protoxylem. This makes the metaxylem more efficient in conduction than the protoxylem. The metaxylem also has few fibers, which are lacking in protoxylem. It is not capable of stretch (unlike protoxylem). However, it is not subjected to strain or stress.
Word origin: meta– (“later”) + xylem, from Greek xúlon (“wood”)
See also:


You will also like...

squirrel
Animal Water Regulation

Animals adapt to their environment in aspects of anatomy, physiology, and behavior. This tutorial will help you understa..

Plant Water Regulation
Plant Water Regulation

Plants need to regulate water in order to stay upright and structurally stable. Find out the different evolutionary adap..

Water Cycle
The Water Cycle

The water cycle (also referred to as the hydrological cycle) is a system of continuous transfer of water from the air, s..

Adaptation Tutorial
Adaptation Tutorial

Adaptation, in biology and ecology, refers to the process or trait through which organisms or the populations in a habit..

Plant biology
Plant Biology

Plantlife can be studied at a variety of levels, from the molecular, genetic and biochemical level through organelles, c..

Early Earth
The Origins of Life

This tutorial digs into the past to investigate the origins of life. The section is split into geological periods in the..

Related Articles...

No related articles found

See all Related Topics