What is the meaning of apex explain it's types
What is the meaning of apex explain it's types
Apex
In botany, apex refers to the highest point or vertex of a plant stem or root. The shoot apex is where fresh stems, leaves, and other parts of a plant grow after the old parts fall off or dry up. In some cases, such as monocot stems, the shoot apex tends to be more elongated.
Apex is mainly classified by two
1. Shoot apex
2. Root apex The Shoot Apex: The terminal part of the shoot with the leaf primordia is the shoot apex where primary organisation of the shoot is initiated.
In size and shape it varies enormously, but in a general way it can be said that the shoot apex is more or less convex in longitudinal section.
The Root Apex:
In comparison to the stem apex the apical meristem of the root is simpler, because of the absence of nodes and internodes and lateral appendages. But it has a protective cap, which acts as the buffer between the root-tip and the soil particles.
As cap occupies the terminal position, the apical meristem is subterminal here. Curiously enough, growth in the root-tip proceeds in two directions opposite to each other—towards the tip in the cap and away from the tip in the root proper.
Similarities between Shoot Apex and Root Apex Ø Both shoot apex and root apex are the growing terminal regions.
Ø Both contain apical meristem.
Ø The tissue in both shoot and root apex are primary tissue.
Difference between Shoot Apex and Root Apex Sl. No.Shoot ApexRoot Apex 1 Shoot apex is positively phototropic. Root apex is negatively phototropic. 2 Shoot apex is negatively geotropic. Root apex is positively geotropic. 3 Apical meristem in shoot apex is terminal in position. Apical meristem in root apex is sub-terminal due to the presence of root-cap. 4 Shoot apex is protected by a crown of young leaves. Root apex is protected by a root-cap. 5 Shoot apex possesses leaf primordia. Leaf primordia are absent in root apex. 6 Shoot apex is dome-shaped. Root apex is hemispherical or cup-shaped. 7 Quiescent centre absent in the shoot apex Root apex is surrounded by a quiescent centre. 8 Cells are comparatively more differentiated in shoot apex. Cells are comparatively less differentiated. 9 Shoot apex is comparatively long. Root apex is comparatively short.
In botany, apex refers to the highest point or vertex of a plant stem or root. The shoot apex is where fresh stems, leaves, and other parts of a plant grow after the old parts fall off or dry up. In some cases, such as monocot stems, the shoot apex tends to be more elongated.
Apex is mainly classified by two
1. Shoot apex
2. Root apex The Shoot Apex:
The terminal part of the shoot with the leaf primordia is the shoot apex where primary organisation of the shoot is initiated.
In size and shape it varies enormously, but in a general way it can be said that the shoot apex is more or less convex in longitudinal section.
The Root Apex:
In comparison to the stem apex the apical meristem of the root is simpler, because of the absence of nodes and internodes and lateral appendages. But it has a protective cap, which acts as the buffer between the root-tip and the soil particles.
As cap occupies the terminal position, the apical meristem is subterminal here. Curiously enough, growth in the root-tip proceeds in two directions opposite to each other—towards the tip in the cap and away from the tip in the root proper.
Similarities between Shoot Apex and Root ApexØ Both shoot apex and root apex are the growing terminal regions.
Ø Both contain apical meristem.
Ø The tissue in both shoot and root apex are primary tissue.
Difference between Shoot Apex and Root Apex Sl. No.Shoot ApexRoot Apex| 1 | Shoot apex is positively phototropic. | Root apex is negatively phototropic. |
| 2 | Shoot apex is negatively geotropic. | Root apex is positively geotropic. |
| 3 | Apical meristem in shoot apex is terminal in position. | Apical meristem in root apex is sub-terminal due to the presence of root-cap. |
| 4 | Shoot apex is protected by a crown of young leaves. | Root apex is protected by a root-cap. |
| 5 | Shoot apex possesses leaf primordia. | Leaf primordia are absent in root apex. |
| 6 | Shoot apex is dome-shaped. | Root apex is hemispherical or cup-shaped. |
| 7 | Quiescent centre absent in the shoot apex | Root apex is surrounded by a quiescent centre. |
| 8 | Cells are comparatively more differentiated in shoot apex. | Cells are comparatively less differentiated. |
| 9 | Shoot apex is comparatively long. | Root apex is comparatively short. |
