Tag: plant growth

Vivipary means that seed remains attached to the plant even during germination. It is an undesirable character for annual crops as they are not able to store under normal condition for coming years.

The phenomenon of generation of whole plant by single cell is totipotency.

• Plant growth regulators function as chemical messengers for intercellular communication. There are currently five recognized groups of plant hormones: auxins, gibberellins, cytokinins, abscisic acid ($ABA$) and ethylene.
• Indole-3-acetic acid ($IAA$, $3-IAA$) is the most common, naturally occurring plant growth regulator of the auxin class. 
  
• $2IP$ (Isopentenyl adenine) is a naturally occurring cytokinin that regulates cell division, development, and nutrient processing in plants.
• Zinc ($Zn$) is not a plant growth regulator. It is one of the eight essential micronutrients. It is needed by plants in small amounts, but yet crucial to plant development.
• So, the correct answer is '$IAA, 2IP, Zn$'.

The cells derived from root apical and shoot-apical meristems and cambium differentiate and mature to perform specific functions. This act leading to maturation is termed as differentiation. During differentiation, cells undergo few to major structural changes both in their cell walls and protoplasm. The living differentiated cells, that by now have lost the capacity to divide can regain the capacity of division under certain conditions. This phenomenon is termed as dedifferentiation. For example, formation of meristems – interfascicular cambium and cork cambium from fully differentiated parenchyma cells. While doing so, such meristems / tissues are able to divide and produce cells that once again lose the capacity to divide but mature to perform specific functions, i.e., get redifferentiated. 

Three concentric regions of primary meristematic tissues develop immediately behind the apical meristem . These primary meristems produce the different tissues of the plant body: the outermost protoderm differentiates into the epidermis, a tissue that protects the plant; the adjacent ground meristem differentiates into the central ground tissues (the pith and cortex); and the procambium differentiates into the vascular tissues (the xylem, phloem, and vascular cambium).

Ethylene affects fruit - ripening. Normally, when the seeds are mature, ethylene production increases and builds - up within the fruit, resulting in a climacteric event just before seed dispersal. The nuclear protein 'Ethylene Insensitive 2' is regulated by ethylene production, and in turn, regulates other hormones including ABA and stress hormones.

Ethylene is a plant hormone. It is also called as ripening hormone. It is responsible for ripening of fruits. Fruit ripening is accompanied by increased rate of respiration. Ethylene rich atmosphere is used to accelerate the process of ripening of fruits like banana.

There are five classes of naturally occurring plant growth regulator. These are auxins, gibberellins, cytokinins, abscisic acid and ethylene. Ethylene is also called as ripening hormone as it is responsible for ripening of fruits. Fruit ripening is accompanied by increase rate of respiration. Due to increased respiration, complex carbohydrates are broken down into simpler sugars and cell wall becomes soft. It inhibits cell division. It is also involved in abscission of leaves, fruits and flowers.

Ethylene is a gaseous plant hormone. It is also called as ripening hormone as it increases ripening of fruits. Fruit ripening is accompanied by increase rate of respiration. Due to increased respiration, complex carbohydrates are broken down into simpler sugars and cell wall becomes soft. It inhibits cell division. It is also involved in abscission of leaves, fruits and flowers.

Many hormone-like abscisic acid (for closing)  cytokinin (for opening) and ethylene (for opening and closing both) are responsible for opening and closing of stomata.