Strand of fluid-carrying vascular tissue extending from the main stem to the base of a leaf is Leaf Trace. Relatively thinner portions of the cell wall that adjacent cells can communicate or exchange fluid through are called Pits. In this article, Leaf traces and Pits will be discussed explicitly. Prolongations …
Read More »External Secretory Structures
External surfaces of the plant bear several secretory structures of epidermal origin or epidermal derivatives or emergences from deeper tissues (Kisser, 1958). These include Glands, Glandular Trichomes, Nectaries, Osmophores, Hydathodes etc. In this article, these external structures of plant will be discussed briefly. Trichomes and glands In some leaves and flowers, more or less …
Read More »Secretory Tissue: A Laticiferous Discussion
The tissues that are concerned with the secretion of gums, resins, volatile oils, nectar, latex and other substances are called Secretory tissues. These tissues are mainly divided into two groups: Laticiferous tissue. Glandular tissue. In this article, Laticiferous tissue will be discussed explicitly. Laticiferous tissue A laticifer is a type of …
Read More »Bark and Lenticel: A Brief Discussion
Bark is the outermost covering of stems and roots of woody plants (especially trees), and is composed of periderm, cortex, and phloem. A lenticel is a porous tissue consisting of cells with large intercellular spaces in the periderm of the secondarily thickened organs and the bark of woody stems and roots of …
Read More »Internal Structure of Wood
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic material – a natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin that resists compression. In this article, Internal structure of Wood …
Read More »Anomalous Secondary Growth
Anomalous secondary growth” is the term under which have been grouped cambial conformations, cambial products, and cambial numbers which differ from the most common “normal” condition, namely, a single cylindrical cambium that produces phloem externally and xylem internally. In this article, Anomalous secondary growth, it’s causes and position will be …
Read More »Periderm: Structure and Development
Periderm is the corky outer layer of a plant stem formed in secondary thickening or as a response to injury or infection. It is a cylindrical tissue that covers the surfaces of stems and roots of perennial plants during early secondary growth; therefore it is not found in monocots and …
Read More »Root-Stem Transition
The change in arrangement of vascular tissues of roots having separate strands of phloem and xylem with exarch protoxylem to collaterally placed phloem and xylem with endarch protoxylem of stem is commonly referred to as root–stem transition. In higher plants root and shoot form a continuous axial structure. In this article, The Transition of Root and Stem …
Read More »Secondary Growth of Dicot Stem and Root
Secondary growth is characterized by an increase in thickness or girth of the plant. It is caused by cell division in the lateral meristem. Herbaceous plants mostly undergo primary growth, with little secondary growth or increase in thickness. Secondary growth is initiated by the activity of the vascular cambium as …
Read More »Primary Structure of Root and Leaf
Root is the underground part of a vascular plant. And Leaf is the flattened outgrowth from stem of a vascular plant. In this article, Primary structure of Root and Leaf will be discussed in detail. Primary Structure of Dicot Root The root of Dicot plants usually consists of Epidermis, Cortex, …
Read More »