You all like stories. In our childhood days our parents and grandparents used to narrate stories for us. Let me tell you a short story for you now. Once upon a time a large elephant approached a group of blind guys as they were crossing a road. Though none of them had seen it, they all knew it was an elephant. How was it possible? They all touched the elephant and made a cumulative decision based on the examination in the below mentioned way.
Each of them went and touched the part they could get their hands on and from what they felt they described the elephant as you see here. The one who touched the trunk said that the elephant is like a snake. The tusk was described as a spear by one. Ears felt like a fan to one. The huge body felt like a giant wall to one. The legs felt like huge tree trunks to someone. The tail was described as a rope. All of them correctly described the external appearance of the part they touched, thinking it was the whole elephant. In this way they were trying to describe the ‘morphology’ of this elephant. Morphology is the branch of Biology that deals with the study of the external form and structure of organisms.
Fig: Story of elephant and bind people
Similarly, when you look at a plant, what are the parts you see with your naked eyes? List out the major parts with functions.
Fig: Morphology of a plant
Phytomorphology is the branch of Biology that deals with the study of the form and structure of plants. A plant possesses different parts, such as the roots, stems, leaves, and flowers. All these parts have distinct functions in plant growth and development. Let’s take a deep dive into the details of morphology of plants and find out the various characteristics and functions of different parts of a plant in this particle.
Table of contents
This kingdom includes multicellular, eukaryotic and producer organisms. They possess chlorophyll. They are mostly autotrophic. From microscopic plants to very complex and evolved forms, the kingdom Plantae includes a diverse range of species. The majority of the vegetation on Earth is made up of flowering plants. They are a collection of advanced and specialised groups. Every organ or component of the plant performs a specific task in the plant body.
A plant body possesses two main fundamental parts as follows:
Both systems function well in quite different environments. The plant's root system grows downward within the soil and aids the plant in anchoring. Leaves, stems, flowers, and fruits make up the shoot system.
The root system is the part of the plant axis that descends (grows downward) into the soil. When a seed germinates, the radicle is the first organ to appear. To form the primary or tap root, it grows longer. By growing lateral branches (secondary and tertiary roots), it establishes the root system. It deeply embeds the plant by spreading out into vast areas of soil. Another crucial job that it does is to bring water and mineral salts up from the soil. From the seed's radicle, the root system grows.
Fig: root system develops from the radicle
It consists of the main root and its branches. The most prominent root present in the centre is called the primary root. It bears several lateral roots called secondary roots. These secondary roots further branches to form tertiary roots and finer rootlets. The tips of rootlets are normally covered with root caps. Behind the root tips it possesses fine outgrowth called root hairs. It is developed from the epiblema (epidermis of the root).
Fig: Parts of the root system
All vascular plants have roots, which are their most significant underground component. This area of the plant is in charge of holding it firmly in place and absorbing essential nutrients, minerals, and water. Food can be stored in it as well. However, not all plants have underground roots; some also have above-ground roots called aerial roots. Mangrove plants, bonsai, and banyan trees are a few examples of plants with aerial roots. Roots play a crucial role in absorbing nutrients as well as anchoring and attaching the plant to various structures like trellises, rocks, and other nearby walls.
Fig: Buttress roots
Some of the important characteristics of the root are listed below:
Root performs two types of functions as follows:
Primary functions of the roots are as follows:
The secondary or accessory functions of the root are as follows:
Fig: Prop roots in banyan tree
Fig: Root nodules
Fig: Velamen roots of orchids
GIF: Parasitic roots of Cuscuta
Fig: Respiratory root (pneumatophores) in Rhizophora
The shoot system is the ascending part of the axis that bears branches, leaves, flowers, and fruits. The shoot system is typically found above ground, however, it can also be modified to be found underground. It develops from the plumule part of the seed.
GIF: Shoot system develops from the plumule
The following are the main parts of the shoot system:
The ascending portion of a plant's axis that bears branches, leaves, flowers, and fruits is referred to as the stem.
Some of the important characteristics of the stem are listed below:
Fig: Structure of stem
Some of the functions of the stem are listed below:
Fig: Leaves exposed to sunlight
Fig: Potato -Tuber
Fig: Stem tendrils
It is characterised as a flat structure that is present on the stem. It develops at the node and bears a bud on its axil.
Fig: Structure of a leaf
The area of the embryo between the cotyledons known as the SAM (Shoot apical meristems) is where leaves are produced. Due to the presence of meristematic cells, multipotent stem cells, that can divide and differentiate into a variety of different cell types, SAM has the capacity to generate the entire shoot system.
Fig: Shoot apical meristem (SAM)
The shoot's apical meristematic zone keeps increasing up the shoot as it expands, eventually taking up a position just above where the last set of leaves had grown. As a result, leaves develop acropetally, that is, one by one from base to tip.
Fig: Position of shoot apical meristem
Some of the characteristics of the leaf are listed below:
Some of the critical functions of leaves are as follows:
GIF: Opening and closing of stomata
Fig: Bulb of onion
GIF: Tendrils coiling around a support
Fig: Insectivorous plants
A flower is a modified shoot with fewer internodes and more appendages sprouting from each node than a normal shoot would have. A stalk called a pedicel that connects flowers to the main stem. The apex produces a variety of floral appendages, including petals, stamens, carpels, and sepals.
Some of the important characteristics of a flower are listed below:
Fig: Different whorls of a flower
The critical functions of a flower are as follows:
It is a ripened ovary which is formed mostly after fertilisation. It is considered a unique feature of angiosperms. The fruit wall is called pericarp. It provides protection to the seeds. It helps in the dispersal of seeds. It possesses lots of nutrients and acts as a good food source.
Fig: Structure of fruit
It is a ripened ovule. It possesses an embryo, food reserves and seed coats. Outer seed coat called testa is formed from the outer integument. Inner seed coat called tegmen is formed from the inner integument. Embryo is the future plant. It possesses one or two cotyledons and an embryonal axis. Seeds provide nourishment to the embryo and protect it. It is the basis of agriculture. It can act as a food source.
Fig: Structure of seed
Q 1. Identify the edible underground stem from the following options.
d. Sweet potato
Answer: Potato is a modified stem. This modified stem develops underground and is known as a tuber. Hence, the correct option is a.
Q 2. Determine which is not a part of a leaf?
Answer: The leaf base is the portion of the leaf that connects to the stem. Stipules are a pair of tiny, leaf-like structures that some plants have at the base of their leaves. Stipules are regarded as a component of the leaf in anatomical terms in a typical flowering plant. A petiole is a name for the leaf's stem.
The leaf blade, also known as the enlarged green portion of the leaf, has veins and veinlets. It acts as the primary site of photosynthesis in the leaf lamina. The stem is not a part of the leaf; leaves are formed on the stem. Stem has internodes and nodes. The nodes on the stem is the region where leaves grow. Hence, the correct option is d.
Q 3. A flower is a modified ___________.
Answer: The flower is described as a modified shoot. Here, the shoot apical meristems convert into floral meristems. The floral meristems produce flowers. Hence, the correct option is b.
Q 4. How do flowers reproduce?
Answer: Pollination is the process through which flowers reproduce. This procedure involves the transfer of male gametes to ovules, where fertilisation takes place. Then the ovules develop into seeds inside a fruit.
Q 1. Why are the leaves of some plants other than green in colour?
Answer: Usually the leaves of a plant are green in colour due to the presence of chlorophyll pigment. There are some plants that possess red to orange colour leaves because these plants possess carotene pigments along with chlorophyll.
Q 2. What would happen if plants lack leaves?
Answer: Without leaves, a plant will die since they are a vital component of the plant. A plant uses its leaves to exchange gases during the transpiration process. By using the process of photosynthesis, leaves also assist in preparing food for themselves.
Q 3. Why are petals a colourful part of a flower?
Answer: Flowers have genetic makeup, much like humans. These plants produce pigments, which result in a spectrum of colours. The carotenoid substance that gives tomatoes and carrots their colour also gives some flowers their yellow, red, or orange colour. This colouration is required to attract pollinating agents.
Q 4. Why do plants produce seeds?
Answer: In order to ensure the survival of the species, plants produce a lot of seeds. The embryo that subsequently develops into a new plant is present in the seed. Seeds result in genetic variations in plants.
Root and Its Parts: Root system, Structure of dicot and monocot root, Order, types, and functions of the root, Root modifications, Practice Problems, and FAQ’s
The Stem : Structure of stem, Functions of stem, Shoot modifications, Practice Problems, and FAQs
The Leaf: Origin, Functions, Parts, Veins and Venation, and Practice Problems, and FAQs