Question

What is the difference between primary and secondary xylem?

Answer 1

Xylem:

1. Xylem is a form of vascular tissue found in plants that distribute water and nutrients from the roots to the stem and leaves.
2. Xylem is in charge of replenishing the whole amount of water molecules lost during transpiration and photosynthesis.
3. They also give the plants mechanical strength.
4. They are found at the vascular bundle's center.
5. They can be found in roots, stems, and leaves.
6. These tissues migrate in a unidirectional fashion (just in one direction — upward).
7. Vessels, tracheid, fibres, and parenchyma cells make up the xylem.
8. It's a sort of transport tissue found in vascular plants.

Primary xylem: It is made of the procambium of the apical meristem.

Secondary xylem: This formation occurs only during secondary growth.

Difference between primary and secondary xylem:

Primary xylem	Secondary xylem
1. Primary xylem is found in all vascular plants' primary plant bodies.	1. It exclusively affects the stems and roots of perennial dicots and gymnosperms.
2. It takes place in the center.	2. It is situated on the outside edge of the main xylem.
3. Primary xylem patches can be identified.	3. The secondary xylem is shaped like a cylinder.
4. The xylem is divided into two parts: protoxylem and metaxylem.	4. Such distinction does not exist.
5. There is no such thing as a radial system.	5. It is traversed by a radial system of xylem rays.
6. There are no yearly rings.	6. It has yearly rings.
7. There is no distinction between sapwood and heartwood.	7. Sapwood and heartwood are distinguishable in big woody trees.
8. Fibres are few or non-existent.	8. In most situations, fibres are abundant.
9. The tracheid and vessels are long and thin-walled.	9. The tracheid and vessels are thinner and shorter than the rest of the body.
10. Tracheary components can thicken in a variety of ways.	10. Pitted thickenings are prevalent in tracheary components.
11. Tyloses are not usually present.	11. Tyloses growth obstructs the arteries and tracheid of older xylem cells.