顶部和侧向分生组织之间的差异

关键区别 - 顶部与侧生生物

Let us first understand what a meristem is, before looking at the differences between apical and lateral meristems.Meristemis a unique plant tissue made of cells that are not fully differentiated and capable of dividing continuously to produce new plant tissues. In addition, these cells possess some other general characteristic features, which include the presence of cube-shaped cells with dense细胞质, one or more prominent nuclei, smallvacuolesin the cytoplasm,plastidsin proplastid stage, presence of homogenous, thin cell walls made up ofcellulose, and the absence of intercellular spaces and ergastic matter. Since these cells have the power of division, theirmetabolic rateis very high compared to the cells in other plant tissues. Classification of meristems is done mainly based on their origin, developmental stages, structure and task. There are three types of meristems according to their position in a plant, namely;apical meristem,intercalary meristem, andlateral meristem. Thekey differencebetween apical and lateral meristem is,apical meristem helps in the初级增长植物whereas侧分生组织有助于植物的继发生长。

What is Apical Meristem?

顶部分生组织位于茎，根及其横向分支的顶端。该分生组织构成植物沿其轴的垂直生长。顶部分生组织是圆顶形的，有两个部分。外层（Tunica）和内部质量（语料库）。它由少量细胞组成，并产生植物的主要永久组织（主要生长）epidermis,xylem, phloem,和地面组织。根尖分生组织被称为根帽的细胞层覆盖。顶端分生组织的细胞具有分生组织的所有一般特征。射击顶点与根顶完全不同。拍摄顶端分生组织产生leaf primordia(which cover and protect the shoot apical meristem), andbud primordia.

What is Lateral Meristem?

Lateral meristems consist of thevascular cambium and cork cambiumand is responsible for the secondary growth of plant tissues.The secondary growth increases the girth of the plant (horizontal growth). Lateral meristem is found along the entire length of the stem and root except at apices. In a cross section of stem or root of a plant that undergoes secondary growth, the lateral meristem can be seen as rings.

What is the difference between Apical and Lateral Meristems?

顶端和侧向分生组织的定义：

Apical meristem:A plant tissue with undifferentiated cells found at the tip of a shoot or root and is responsible for the primary growth.

侧生组织：A plant tissue with undifferentiated cells that is found along the length of stems and roots and is responsible for the secondary growth.

Features of Apical and Lateral Meristem:

Location:

Apical meristem:Apical meristems are positioned at the apices of stems, roots, and their lateral branches.

侧生组织：Lateral meristems are found along the entire length of stem and root except at apices.

Growth Type:

Apical meristem:Primary growth takes place at apical meristems.

侧生组织：Secondary growth takes place at lateral meristems.

Growth:

Apical meristem:Apical meristem increases the length of a plant along its vertical axis,

侧生组织：Lateral meristem increases the girth of a plant.

Content:

Apical meristem:Apical meristem gives rise to lead primordia and bud primordia, unlike lateral meristem.

侧生组织：与根尖分生组织不同，侧向分生组织由血管形成和软木形成型组成。

组织类型：

Apical meristem:Apical meristem gives rise to primary permanent tissues including epidermis, xylem, phloem, and ground tissues.

侧生组织：Lateral meristem gives rise to wood, inner bark and outer bark.

Image Courtesy:

“Apical Meristems in Crassula ovata” by Daniel,levine – Digital Camera.(CC BY-SA 3.0)viaWikipedia

“Japanese Maple Bark” by David Shankbone- Own work.(CC BY-SA 3.0)viaCommons