Plant Physiology

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Plant Physiology Meaning

Plant physiology is basically a study of plant parts and their function. Plants are as important as every living orgasm on the earth. They give us oxygen to breathe. They were required to develop a process to survive with the separation of water and CO2. It includes the study of plant different body parts, like stems, leaves, roots, and reproductive organs. It also helps us to research plant processes like mineral nutrition, photosynthesis, transportation, respiration, and plant growth and development.

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Plant Parts And Functions

Plants have different body parts like Roots, Stem, Leaves, Flowers, and Fruits. Following are the different parts of plants and their functions: - 

  • Roots

Roots are known as the foundation system for the plants and keep the plants firmly grounded in the soil. The main function of the root is water and minerals absorption from the soi. It helps to synthesize plant growth and regulates reserve food material.

  • Stem

The stem is a part of the plant found above the ground. The color of the tree stem is brown, while the younger stems are green. The important functions performed by the stem are: - 

    • It facilitates the important process of photosynthesis in plants.

    • It offers a proper structure to a plant, which later helps it develop into a tree.

    • Another important function of the stem is to carry up leaves, flowers, buds, and fruits to the plant. 

    • It transports water, minerals, and ready food from the leaves to other parts of the plant.

    • The stem also helps to protect phloem and xylem and also allows them to perform their normal functions.

  • Leaves

Leaves are another essential part of a plant. They contain chlorophyll that helps the plant with the process of photosynthesis using sunlight, carbon dioxide, and water. A leaf has three main parts- leaf base, lamina, and petiole. The main functions of a leaf are: -

1) Transpiration: Apart from photosynthesis, leaves play an essential role within the removal of far more than water from plants through tiny pores called stomata. 

2) Photosynthesis: Green leaves prepare the food with the help of water and carbon dioxide in the presence of sunlight with the process of photosynthesis.

3) Reproduction: Leaves of some plants also help with the reproduction. For e.g., leaves of Bryophyllum produce a brand new Bryophyllum plant. 

  • Flowers

Flowers are the foremost beautiful and vibrant part of a plant. They are, in fact, the part of a plant that reproduces. A flower has four major components: petals, sepals, stamens, and carpels.

  • Fruits

Fruits are the most important feature of a seed plant. It’s a mature ovary that develops after fertilization. Some fruits are produced without fertilization and are called Parthenocarpy fruits.

Mineral Nutrition in Plants

It is essential for the growth of the plant. It gives insight methods to identify the essential elements of the plants. These minerals in plants spot their essentiality, deficiency symptoms, and mechanism of absorption elements. It also conveys the importance of the biological process. Macro and micronutrients present in plants do essential processes like cell-membrane permeability, osmotic concentration of cell sap and its maintenance, enzyme activity, and then on.

Nutrition Transportation in Plants

Plants have a definite system (xylem and phloem), which helps in transporting nutrients and water from roots to any or all the parts of the plant through translocation. Transport of water and nutrients in rooted plants is unidirectional or multidirectional. Modes of transportation can either be passive, which occurs through diffusion, facilitated diffusion to be precise, or maybe through effective methods meted out by specific membrane proteins, which are called pumps. 

Photosynthesis in Higher Plants

Photosynthesis is essential because it is the primary source of food for all living entities on earth. It releases oxygen within the atmosphere, which all living organisms inhale to breathe. It takes place in chloroplasts through light and dark reactions using four pigments i.e. xanthophyll, chlorophyll, chlorophyll, carotenoids. Extracting energy from oxidizable substances and storing within the kind of bond energy is phosphorylation. In plants, cyclic and non-cyclic photophosphorylation occur. 

Respiration in Plants

Food that’s required for keeping processes comes from photosynthesis. Metastasis ends up in the discharge of energy, which is employed for the synthesis of ATP, which involves glycolysis. Aerobic respiration ends up in complete oxidation of organic substances within the presence of oxygen, which is common in higher organisms. Another vital aspect of respiration is the ratio of the degree of CO2 released to the quantity of oxygen consumed.

FAQ (Frequently Asked Questions)

1. Write short notes on the physiology of Plant Parts?


Leaves are an important organ of the plant. They’re the first center of photosynthesis and grow in different kinds of shapes and sizes. 


The stem provides support and structure to the plant. They perform many essential functions like plant growth, compete and survive in several environments, etc. The structure of the stem differs in numerous species.


The roots grow underground and absorb water and nutrients from the soil. That’s why they’re a vital part of the plant.

Xylem and Phloem

Xylem and phloem are also called sap. These form the vascular tissues of the plant. They transport water, sugars, and other essential substances between the roots, stem, and leaves.

2. Elaborate on the process of Plant growth and development.

The process of plant development starts from germination under favourable environmental conditions. Plant growth is indeterminate as they preserve their capacity to grow throughout their lives thanks to the presence of meristems. The expansion of plants is, however, measurable through parameters like – dry weight, increase in fresh weight, length, area, volume, cell number, etc. the amount of plant growth is categorized into three phases – meristematic, elongation and maturation. Plant growth regulators control the expansion of plants. Plants also produce compounds like phytochromes that are light sensitive and stimulate the development of the plant in response to environmental signals.