ACME SMART PUBLICATION
Chapter 5
Morphology of flowering plants
Angiosperms have a wide range of exterior forms or morphology, but they all have roots, stems, leaves, flowers, and fruits in common. Flowers and fruits may be present. The root system of a flowering plant is underground, whereas the component above ground is called the shoot system.
The Root
All vascular plants have roots, which are a crucial subterranean component. This portion of the plant is primarily responsible for attaching it to the ground and absorbing the soil's necessary mineral components, nutrients, and water. It can also be used to keep food.
Types of roots:In the majority of dicotyledonous plants, direct radicle elongation results in the creation of the main root that grows inside the soil. It has lateral roots of several orders, referred to as secondary, tertiary, and so on. This is called the taproot system, as shown in the mustard plant. It is made up of the major roots and their branches. The primary root of monocotyledonous plants is short-lived and is replaced by a vast number of roots.As shown in the wheat plant, these roots grow from the base of the stem and form the fibrous root system.
Adventitious roots emerge from portions of the plant other than the radicle in some plants, such as grass, Monstera, and the banyan tree. Absorption of water and nutrients from the soil, appropriate anchorage of plant parts, storage of reserve food material, and synthesis of plant growth regulators are the key tasks of the root system.
Regions of a root:The root cap is a thimble-like structure that covers the root at its tip. It shields the root's fragile apex as it travels through the soil. Meristematic activity occurs a few centimeters above the root cap. This region's cells are tiny, thin-walled, and have thick protoplasm. They repeatedly divide. The cells closest to this region experience rapid elongation and expansion, and they are responsible for the root's length growth. The elongation region is the name given to this area. The elongation zone's cells mature and differentiate throughout time. As a result, the zone proximal to the region of elongation is known as the maturation zone.Root hairs are incredibly tiny and fragile thread-like structures formed by epidermal cells in this region. The soil's water and minerals are absorbed by these root hairs.
Modifications of a root:Some plants' roots change shape and structure, allowing them to perform roles beyond water and mineral absorption and conduction. They've been altered to provide support, food storage, and breathing. Carrot, turnip, and sweet potato adventitious roots are used for the storage of food in plants. Prop roots are the hanging structures that support a banyan tree. Similarly, maize and sugarcane stems have supporting roots that emerge from the lower nodes of the stem. They are called Stilt roots. Many roots emerge from the ground and climb vertically upwards in plants like Rhizophora that flourish in swampy environments. Pneumatophores are roots that aid in the acquisition of oxygen for breathing.
