As we know that many plants have a vascular system and this system allows plants to absorb water and mineral from the soil. There are two types of vascular tissues that are mainly involved in this process namely xylem and phloem.
In this article, we are going to understand the difference between xylem and phloem.
Related Topic: Mineral Transportation in Plants and Its Means
What is Xylem
The xylem in plants are responsible for the transportation of water from roots to stems and leaves, along with the transport of nutrients. Here, the transportation works due to capillary action. The name has been derived from the Ancient Greek word ξύλον, meaning “wood”. This name was introduced by Carl Nageli in 1858.
Xylem has got two difference cells namely tracheids and vessels for transporting minerals and water.
There are two types of xylem:
- Primary xylem, which is formed during primary growth from procambium of the apical meristem.
- Secondary xylem, which is formed during secondary growth from vascular cambium of the lateral meristem.
What is Phloem
Phloem is the tissue that transports the soluble organic compounds made during photosynthesis. This transport process is called translocation. The name has been derived from the Ancient Greek word, φλοιός, which means “bark”, as in tree bark. This name was also introduced by Carl Nageli in 1858.
The phloem tissue consists of the following cells:
- Conducting cells are responsible for transporting sugars throughout the plant. Also known as sieve elements.
- Parenchyma cells are used for food storage. Companion cells and Albuminous cells comes under this category.
- Supportive cells are used to transport sugars and may also contain cells that have a mechanical support function. Fibres and Sclereids are part of supportive cells.
Difference between Xylem and Phloem
Below are some of the major differences between the two types of vascular tissues:
|Vascular tissue that carries food and water from roots to leaves.||Vascular tissue carries various substances like sugar from leaves to roots.|
|Consists of fiber, tracheids, vessel elements, xylem parenchyma, xylem sclerenchyma, and xylem fibers.||Consists of sieve cells, sieve tubes, phloem fibers, parenchyma, and companion cells.|
|Provides mechanical support.||No mechanical support.|
|Xylem constitutes the bulk of the body.||Phloem constitutes a small part of the body.|
|Located in the center of the vascular bundle.||Located on the outermost side of the vascular bundle.|
|Responsible for replacing the total amount of lost water molecules through transpiration and photosynthesis.||Responsible for transporting proteins and mRNAs throughout the plant.|
|Xylem fibers are small.||Phloem fibers are large.|
Xylem transports water and minerals from roots to leaves, whereas phloem carries the food prepared by the leaves to different parts of the plant.
Xylem is located in the center of the vascular bundle, while phloem is located in the outermost part of the vascular bundle.
Three major differences are discussed below:
1. Xylem transports water and minerals from roots to leaves, whereas phloem carries the food prepared by the leaves to different parts of the plant.
2. Xylem is unidirectional whereas Phloem is bidirectional.
3. Xylem consists of fiber, tracheids, vessel elements, xylem parenchyma, xylem sclerenchyma, and xylem fibers, whereas phloem consists of sieve cells, sieve tubes, phloem fibers, parenchyma, and companion cells.