Biology class 11 syllabus includes a detailed chapter on Anatomy of Flowering Plants that introduces us to a whole new level of tissue structure in plants. Further, it makes us understand the functional organisation in plants. For students who are pursuing biology in class 11, we have compiled notes of this chapter from NCERT Biology class 11. These notes in the blog would help you for a quick revision of the chapter!
This Blog Includes:
- Anatomy of Flowering Plants: Plant Tissues and Their Types
- Anatomy of Flowering Plants: Understanding the Tissue System
- Anatomy of Dicotyledonous and Monocotyledonous Plants
- Anatomy of Flowering Plants: Secondary Growth
- Important Questions
Anatomy of Flowering Plants: Plant Tissues and Their Types
Tissues are a group of cells performing a similar function with a common origin. Plant tissues are of various kinds. As per the NCERT biology class 11, plant tissues are classified into two main groups – Meristematic Tissues and Permanent Tissues – based on the capability of the division of cells.
The cells in meristematic tissues can divide themselves. The cell division happens in meristems. They are responsible for the growth of plants. As per the anatomy of flowering plants chapter, each plant has different kinds of meristems, which are broadly classified as:
- Apical Meristem: This meristem happens to be at the tip of shoots & roots and produce primary tissue. It increases the plant length and consists of axillary bud, which helps with the formation of leaves
- Intercalary Meristem: It is the meristem present between the mature tissues. It produces primary tissues that are intercalary meristems. It is present in grasses and helps in regenerating the parts removed by herbivores
- Lateral Meristem: This meristem is present in the mature region of shoots and roots of various plants. It produces secondary tissues and appears after primary meristem and is solely responsible for secondary growth
These cells are derived from meristematic tissues. They are functionally and structurally specialised because of their inability to further divide. The permanent tissues are broadly classified as:
These are made of only one type of cell. They have the following characteristics-
- Parenchyma: These are living, isodiametric thin cells with intercellular spaces. They are composed of cellulose and perform functions like storage, photosynthesis and secretion
- Collenchyma: These are tightly packed living cells and are thick at the corners. They provide technical support in the growing plants
- Sclerenchyma: These are long cells that are dead cells with lignified and thick walls. On the variation of their structure, form, origin, and development, they are classified further as fibres and sclereids.
Complex tissues are made of more than one type of cells. They usually work together and are classified as:
- Xylem: It is a conducting tissue for movement of minerals and water from roots to leaves and stem. It is mainly composed of vessels, tracheids, xylem parenchyma, and xylem fibres
- Phloem: It helps with the transportation of food from leaves to various plant parts. It is composed of companion cells, sieve tube elements, phloem fibres, and phloem parenchyma.
Anatomy of Flowering Plants: Understanding the Tissue System
In the chapter anatomy of flowering plants, the tissue system explains variation in tissues depending on where they are situated in the plant body. Depending on their location, the functions and structure also vary. These tissue systems are further classified into three sub-types:
Epidermal Tissue System: It forms the outermost part of the plant body. It comprises of:
- Epidermis: Outermost layer of the plant’s body
- Cuticle: A thick waxy layer covering epidermis to prevent water loss.
- Epidermal Hair: Helps with absorbing minerals from soil and water.
- Stomata: Helps in regulating the process of gaseous exchange and transpiration.
- Trichomes: Prevents water loss during transpiration.
Ground Tissue System: Every tissue except vascular bundles and epidermis consist of ground tissue. It is formed of collenchyma, parenchyma, and sclerenchyma. In the primary roots and stems, parenchymatous cells are present. Whereas, leaves consist of the thin-walled chloroplast.
Vascular Tissue System: It consists of complex tissues. The vascular bundles are formed from xylem and phloem.
Anatomy of Dicotyledonous and Monocotyledonous Plants
The class 11 anatomy of flowering plants chapter, includes an in-depth understanding of tissue composition of the stem, plant, and roots. Let’s look at their structural composition:
Anatomy of Root
|Dicotyledonous Root||Monocotyledonous Root|
|It has a narrow cortex||It has a wide cortex|
|A less thickened endodermis with prominent Casparian strips||Highly thickened endodermis with visibility of Casparian strips in young roots only|
|Between 2 to 5 xylem and phloem bundles||There are more than 6 xylem and phloem bundles|
|Very small pith, mostly absent.||A well-developed pith is present|
|Secondary growth happens with the help of cork cambium and vascular cambium||No secondary growth|
Anatomy of Stem
|Dicotyledonous Stem||Monocotyledonous Stem|
|Ground tissues are composed of cortex, endodermis, pith, and pericycle||Similar cells are there in ground tissues|
|Open vascular bundles with a ring-like arrangement||Closed vascular bundles are scattered throughout the ground tissue|
|The presence of cambium in between xylem and phloem results in secondary growth of the stem||No secondary growth|
Anatomy of Leaf
|Dicotyledonous Leaf||Monocotyledonous Leaf|
|It is also known as a dorsiventral leaf||Popularly known as an isobilateral leaf|
|Fewer stomata on the upper side of it is completely absent||Presence of stomata on both surfaces of the epidermis|
|Two mesophyll – upper palisade and lower spongy parenchyma||Undifferentiated mesophyll|
|The kidney-shaped guard on the stomata||Stomata guard is bell-shaped|
Anatomy of Flowering Plants: Secondary Growth
The concluding topic of the chapter anatomy of flowering plants explains the secondary growth as an increase in girth in the plants. Mainly, dicotyledonous plants exhibit secondary growth. There are two tissues involved in the secondary growth – vascular cambium and cork cambium.
- Vascular Cambium: It is the meristematic layer that cuts off the xylem and phloem. In between the xylem and phloem, it is present as a single layer. With time, it transforms into a complete ring
- Cork Cambium: It is the protective layer that forms in the cortex layer of the stem with time. It comprises thin rectangular cells that are impervious to water
Here are a few important questions that would make sure you are thorough with the chapter anatomy of flowering plants –
- What is the role of pith in a stem?
- Where do you find Casparian strips? Mention their significance.
- State the functions of trichomes.
- Differentiate lenticels and stomata.
- Where is chloroplast located in a leaf?
Hopefully, through these notes of class 11 biology for the chapter anatomy of flowering plants will help you understand the chapter. Your effective steps towards your dream career are just an e-meeting away! Yes, book a free counselling session with our career experts at Leverage Edu and they will guide you the best. Hurry Up!