Table of Contents
Definition:
Growth is a very important part of every living thing. It is an irreversible and permanent metabolic process. It can be plants, animals, birds, or insects, all simple, and the most complex living species, including the Growth-Growing process. Plants have the unique ability to grow continuously during their life cycle. The whole process of plant growth and development is carried out by specialized cells – the meristems.
Growth is an important, natural, and irreversible factor. Like living things, every plant grows but, unlike humans, plants have unique growth characteristics. They grow throughout their lives. Plant growth occurs in an orderly fashion. This process of growth is defined as plant development.
Plant growth is an irreversible and permanent growth in the size of plant parts, organs, tissues, the whole plant, or individual cells. Growth is a very important part of living plants, just like any other living thing. Plant growth is also associated with metabolic processes such as catabolism and anabolism that require energy depletion.
Growth in plants is an open-source process that is unrestricted and some cells are constantly dividing and helping to increase the size of the cell or tissue. Frequent cells are called meristematic cells.
Plant growth is moderate as an increase in protoplasmic content occurs. Also, an increase in new or dry weight occurs an increase in height and size, and an increase in the number of occurring cells that can all be measured.
Three Stages of Plant Growth
The growing season is divided into three stages, namely –
- Meristematic or Structural Category
The root zone of the plant consists of meristematic cells that continue to divide and are isodiametric (with no spaces between cells), and that area is called the meristematic zone; here, the meristematic zone cells have a rich protoplasm with a large and distinct nucleus. The cell walls of these cells are naturally important, thin, and contain cellulose. These cells have a white plasmodesmata connection.
Cells in this plant region continue to divide rapidly. The meristematic region of a plant usually comprises a large nucleus. Cells exist to stimulate the early stages of plant growth. These are present in the roots and shoots of all plants.
- Elongation Category
Cells located near the meristematic cells are present in the stretch phase. These cells multiply due to the expansion of the existing vacuole in the cell hence the area is called the stretch area. Cell proliferation and the formation of new cell walls occur in existing cells in the proliferation phase. Adjustment as large vacuoles occur in cells here.
- Maturity Phase
The following cells found after stretching are present in the maturation phase and acquire a larger size. They do not degenerate further after reaching the stage of maturity. The maturation zone is found as the phase of mass fragmentation in which cells divide to perform special functions in plants.
Knowing these three stages of cell growth, we can say that cell division, cell proliferation and cell division are the various processes that take place in these stages. The first two stages lead to an increase in plant size and the third stage leads to cell maturity. During differentiation, cells undergo structural changes in the protoplasm and cell wall.
Arithmetic and Geometric Pattern Growth
Crop Growth Rate – Defined as growth during unit time. The two types of plant growth are
Mathematical Growth in Plants
When plant cells are mitotic, two cells are made up of a single cell. In these two cells, one continues to divide and the other divides into separate structures. The front cell then divides and forms two cells and then another continues to divide and then one separates. Now, we have two cells separated from the original cell. Similarly, a pattern is formed and a gradual increase in plant size occurs.
We can represent this category in the form of a line graph in relation to plant height compared to time.
To calculate the results of the Arithmetic Growth curve, the Formula is as follows:
Lt = L0 + rt
There, L = plant height
Lt = length during ‘t’ or after ‘t’
L0 = Length for the first time
r = growth rate
t = interval when calculating the plant growth rate
Growth of Geometry in Plants
In this case, the cell divides into a mitotic cell and forms two cells. Both cells then divide to form two more cells in one. Thus, the number of cells now doubles in each phase. The cell number will be 2, 4, 8, 16, 32, 64, … and so on. In contrast to the stages of arithmetic growth, here no cell division occurs. The cellular growth rate is very rapid here in the geometric phase and when growth reaches a peak, it later begins to slow down and later stabilizes due to certain limiting factors. The growth of the geometric plant can be represented by the following S-shaped graph with the Sigmoid Growth curve in the plants.
Lag Phase – It is a slow phase in which cell division is slow.
Entry Phase – Here, growth is very fast and is known as the refractive phase as well. A steep curve is being built.
Stable or Stable Phase – Here, growth is stable or stable and consistent.
The formula for the Sigmoid Growth Curve is as follows:
Wt = W0 × rt
W0 = size for the first time
Wt = size during t or after t
r = growth rate
t = time
e = the basis of the natural logarithm
Growth is a natural process and unlike humans, plants have different types of growth. The process that facilitates full growth is a process known as plants in which there is sunlight, water, and organic compounds to produce food in the form of ATP. This helps the plant to grow and provide energy to each cell of its structure.
Factors for plant growth
Some of the characteristics of plant growth are listed below:
- Plant Growth Unrestrained: Plants have the roots present in the roots and grow both. Meristems provide the right response to key growth. Due to the presence of only the meristems, the plants grow endlessly throughout their lives. Meristem has the power to isolate and propagate itself. This is because plant growth is said to be unrestricted.
- Plant Growth Rated: Growth only indicates a normal increase in protoplasm. Plant growth is measured by the increase in cell number, location, volume, height, etc. In general, plant growth is difficult to measure, which is why the increase in plant growth rate is accurately measured using a protoplasm increment. Increased plant growth and protoplasm share equally
Chloroplast is the site of photosynthesis. It is present in the mesophyll cell of the leaf. Chloroplast contains chlorophyll pigment.
Example of active transport in plants
Some examples of active transport in plants include: Ions moving from the soil into plant roots. Transportation of chloride and nitrate from the cytosol to the vacuole. Sugars from photosynthesis move from leaves to the fruit.
Also read: Important Topic Of Biology: Plant Growth Rate
FAQs
What are the key elements needed for plant growth?
The four main factors that affect plant growth and development are water, light, temperature, and nutrients. All four of these nutrients affect plant growth hormones which help in faster growth. Unnecessary variations in any of the four elements can lead to increased plant stress and thus alter the pattern of plant growth and inhibitory growth occurs. Therefore, the necessary conditions for plant growth must be carefully studied in order to grow properly.
What is the Plant Growth Rate?
Plant growth can take place in two ways that include arithmetic growth and geometric growth. These two types of growth in plants help us in calculating the plant growth rate; it can be studied and measured with the help of graphical representation w.r.t. Height/Size/Weight of the plant and time. The plant growth rate, therefore, is the percentage change of a specific variable like height/weight/size of the plant’s cell/tissue/organ within a specific time period.
What stage of plant growth comes first?
The first stage of the growth of any plant is the seedling stage. When the first roots and shoots are formed, the seedling usually has only 5 leaves. After the stage is completed, two more leaves grow. The shoots and roots grow continuously until the first tiller appears.
