What does cell elongation mean?

The term elongation will be used for any permanent enlargement of cells already formed by differentiation. As the size of a plant cell is determined by the extent of the surface of its wall, cell elongation may be defined also as any permanent increase in the surface of the cell wall.

First of all, the majority of cell elongation occurs after termination of cell division and, therefore, the actions of proliferation factors and cell expansion factors are separated in time. In addition, some signals, such as auxin, regulate both proliferation and elongation of cells [9]–[11].

Beside above, what is region of elongation? The zone of cell elongation is the region in which newly formed cells by the activity of apical meristem start elongating. Different regions of growth are very distinct in growing roots. These regions are: Zone of cell elongation. Maturation zone or zone of cell differentiation.

Accordingly, how does auxin cause cell elongation?

Auxin is a plant hormone produced in the stem tip that promotes cell elongation. Auxin moves to the darker side of the plant, causing the cells there to grow larger than corresponding cells on the lighter side of the plant. As long as sufficient auxin is produced by the apical meristem, the lateral buds remain dormant.

What is elongation phase of growth in higher plant?

Elongation Phase The cells in the zone just after the meristematic region represent the phase of elongation. The characteristics of cells in this zone are cell enlargement, increased vacuole formation and new cell wall deposition.

What are the types of auxin?

Auxin molecules are one of five major types of plant hormone. The other major groups are the gibberellins, cytokinins, ethylene, and abscisic acid. Auxin was the first of these groups to be identified, and was chemically isolated in the 1930’s. The most widespread auxin is indoleacetic acid, or simply IAA.

What happens in the zone of elongation?

The zone of elongation is where the newly-formed cells increase in length, thereby lengthening the root. Beginning at the first root hair is the zone of cell maturation where the root cells differentiate into specialized cell types. Cell division occurs in the apical meristem.

What is auxin and its function?

The main function of auxin is to help plants grow. Auxin stimulates plant cells to elongate, and the apical meristem of a plant is one of the main places that auxin is produced. Not only does auxin stimulate cell elongation, but it can also help repair wounds on the plant.

Who discovered auxin?

Charles Darwin

How does auxin travel through a plant?

Auxin moves through the plant by two mechanisms. It passes in the sap moving through the phloem from where it is synthesized (its “source”, usually the shoot) to a “sink” (e.g., the root). It also passes from cell to cell by the following mechanism.

How are gibberellins produced?

Chemically speaking, gibberellins are actually acids. They are produced in the plant cell’s plastids, or the double membrane-bound organelles responsible for making food, and are eventually transferred to the endoplasmic reticulum of the cell, where they are modified and prepared for use.

What is tropism in biology?

A tropism (from Greek τρόπος, tropos, “a turning”) is a biological phenomenon, indicating growth or turning movement of a biological organism, usually a plant, in response to an environmental stimulus. Tropisms are typically associated with plants (although not necessarily restricted to them).

What is the function of cytokinin?

Cytokinins are plant hormones that cause increased cell division by stimulating the process of mitosis. They are made naturally by plants but have been synthesized by humans. Increased mitosis results in plant growth and the formation of shoots and buds, as well as the development of fruits and seeds.

What is the main function of auxin?

Auxins promote stem elongation, inhibit growth of lateral buds (maintains apical dominance). They are produced in the stem, buds, and root tips. Example: Indole Acetic Acid (IA). Auxin is a plant hormone produced in the stem tip that promotes cell elongation.

What are the uses of auxin?

They are used in agriculture and horticulture to have a specific effect. Auxins were the first class of plant hormones to be discovered. Their main function is to help plants grow and auxin stimulates plant cells to elongate . The apical meristem of a plant is one of the main places where auxin is produced.

How is auxin transported?

In the primary root, auxin is transported acropetally (see Glossary, Box 1) towards the root tip by a PIN-dependent route through the vascular parenchyma and through the phloem, with subsequent AUX1-dependent unloading into protophloem cells (Friml et al., 2002a; Swarup et al., 2001).

How do auxin and cytokinin work together?

Auxin helps cells elongate, but it doesn’t work alone. Cytokinins promote cell division (cytokinesis) and are produced in roots, embryos and fruits, or wherever there is actively growing tissue. However, cytokinins need auxin to induce cell division. The ratio of cytokinins to auxin determines where cells will develop.

What are the 5 plant hormones?

Understanding Plant Hormones Hormones – Mighty Messengers! Hormones get things done. The Big Five. We’ll cover five major types of plant hormones: auxin, gibberellin, cytokinin, ethylene, and abscisic acid. AUXIN. You’ve seen auxin in action. GIBBERELLIN. CYTOKININ. ETYLENE. ABSCISIC ACID.

How does auxin promote root growth?

Auxins are a powerful growth hormone produced naturally by plants. They are found in shoot and root tips and promote cell division, stem and root growth. They can also drastically affect plant orientation by promoting cell division to one side of the plant in response to sunlight and gravity.