What are Meristematic Tissues? | Infinity Learn

Summary

This educational video script explores the concept of meristematic tissues in plants, which are responsible for growth. It introduces three types of meristematic tissues: apical, lateral, and intercalary, each with a distinct role in plant development. Apical meristems are found at the tips of stems and roots, increasing the plant's length. Lateral meristems, or cambium, contribute to the plant's girth. Intercalary meristems are located at the base of leaves or internodes, aiding in the growth of twigs into branches. The script also touches on the cells' need for energy and nutrition and their initial undifferentiated state, which changes post-growth into specialized tissue components.

Takeaways

• 🌿 Plants have two types of tissues: dividing tissues and non-dividing tissues.
• 🔬 Dividing tissues in plants are referred to as 'meristematic' tissues, which originates from the Greek word 'meristos' meaning 'divided'.
• 📍 Meristematic tissues are found in areas of the plant where growth occurs, such as the tips of stems and roots.
• 🌱 There are three main types of meristematic tissues: apical, lateral, and intercalary meristems.
• 🌱🌱 Apical meristem is located at the growing tips of stems and roots and is responsible for increasing the length of the plant.
• 🌱🌲 Lateral meristem, also known as the cambium, is found on the sides of the plant and contributes to the increase in girth.
• 🌱🍃 Intercalary meristem is found at the base of leaves or internodes and aids in the growth of twigs into branches.
• 💧 Meristematic tissues are very active and require a lot of energy and nutrients due to their high metabolic activity.
• 🔄 Initially, meristematic tissues are undifferentiated but specialize into various types after contributing to the plant's growth.
• 🔄🌳 Meristematic tissues perform the function of 'simple growth' before they mature and differentiate into specialized components.

Q & A

What are the two types of tissues found in plants?

The two types of tissues found in plants are dividing tissues and non-dividing tissues.

What is the technical term for dividing tissues in plants?

The technical term for dividing tissues in plants is 'meristematic tissues'.

What is the origin of the word 'meristematic'?

The word 'meristematic' comes from the Greek word 'meristos', which means 'divided'.

Where are meristematic tissues typically found in plants?

Meristematic tissues are typically found in areas of the plant where growth occurs, such as the tips of stems and roots.

How many different parts of a plant contain meristematic tissues?

There are three different parts of a plant that contain meristematic tissues.

What are the three main types of meristematic tissues?

The three main types of meristematic tissues are apical meristem, lateral meristem, and intercalary meristem.

What is the function of apical meristem tissues in plants?

Apical meristem tissues are found in the growing tips of stems and roots and help increase the length of the plant.

Where is the lateral meristem located and what is its function?

The lateral meristem is located in the girth or cambium of the plant and its function is to increase the girth of the plant.

In which part of the plant is intercalary meristem found, and what does it facilitate?

Intercalary meristem is found at the base of leaves or in the internodes, and it facilitates the growth of twigs into branches.

What is a characteristic of cells in meristematic tissues?

Cells in meristematic tissues are filled with cytoplasm, requiring a lot of energy and nutrition to carry out their functions.

How do meristematic tissues change after the plant has grown?

After the plant has grown and the meristematic tissues have matured, they change characteristics and differentiate into components of a single tissue, with division of labor taking place only after maturity.

What is the initial state of meristematic tissues before they differentiate?

At the initial stages, meristematic tissues are not differentiated into any specific types and exhibit the same function of 'simple growth' of the plant.

Outlines

00:00

🌿 Introduction to Meristematic Tissues

This paragraph introduces the concept of meristematic tissues in plants, which are responsible for growth. It explains that plants have two types of tissues: dividing and non-dividing. The dividing tissues are further classified into three main types based on their location: apical, lateral, and intercalary meristems. Apical meristems are found at the tips of stems and roots, contributing to the length of the plant. Lateral meristems, also known as the cambium, are responsible for increasing the girth of the plant. Intercalary meristems are located at the base of leaves or internodes and facilitate the growth of twigs into branches. The paragraph also highlights that these tissues are initially undifferentiated and only specialize after contributing to the plant's growth.

Keywords

💡Dividing Tissues

Dividing tissues, also known as meristematic tissues, are crucial for plant growth as they are responsible for cell division and the subsequent increase in plant size. In the video, it is mentioned that these tissues are found in areas where growth occurs, such as the tips of stems and roots, and are essential for the plant's development. The script explains that meristematic tissues are not differentiated at first but later specialize into various types after contributing to the plant's growth.

💡Non-Dividing Tissues

Non-dividing tissues are plant tissues that do not undergo cell division. They are contrasted with dividing tissues in the script, highlighting the different roles they play in a plant's structure. While dividing tissues are active in growth, non-dividing tissues are involved in other functions such as support and protection. The video script teases that these will be explored in more detail in a future lesson, suggesting they are equally important for understanding plant biology.

💡Meristematic Tissues

Meristematic tissues are a type of dividing tissue derived from the Greek word 'meristos' meaning 'divided'. They are the focus of the video script, as they are responsible for the growth of plants. The script explains that these tissues are found in specific areas of the plant where growth is observed, such as the apical and lateral meristems, and are named differently based on their location within the plant.

💡Apical Meristem

The apical meristem is one of the three main types of meristematic tissues discussed in the video. It is found at the tips of stems and roots and is responsible for increasing the length of the plant. The script uses the apical meristem as an example to illustrate how meristematic tissues contribute to the elongation growth of plants, which is a critical aspect of plant development.

💡Lateral Meristem

Lateral meristem, also known as the cambium, is another type of meristematic tissue that is responsible for increasing the girth or diameter of the plant. The video script explains that this tissue is found on the sides of the plant, contributing to its radial growth. The cambium is particularly important in woody plants where it allows for the thickening of stems and roots over time.

💡Intercalary Meristem

Intercalary meristem is the third type of meristematic tissue mentioned in the script. It is found at the base of leaves or in the internodes, which are the spaces between nodes. This tissue facilitates the growth of twigs into branches, showing how meristematic tissues can be involved in various growth patterns within a plant.

💡Growth

Growth in the context of the video script refers to the increase in size and development of plant parts. It is a central theme as the video discusses how different types of meristematic tissues contribute to various aspects of plant growth, such as length, girth, and branching. The script makes it clear that growth is not uniform across all parts of the plant but is restricted to areas with meristematic tissues.

💡Differentiation

Differentiation in plants refers to the process by which initially undifferentiated cells become specialized into specific types with distinct functions. The video script mentions that meristematic tissues start as undifferentiated and only later specialize after they have contributed to the plant's growth. This process is crucial for the development of the plant's various tissues and organs.

💡Cytoplast

Cytoplasm is the jelly-like substance within cells that contains many of the cell's organelles and is essential for cellular functions. The script notes that cells in meristematic tissues are filled with cytoplasm, indicating their high metabolic activity and need for nutrients to support cell division and growth.

💡Cambium

The cambium is a lateral meristematic tissue that is specifically responsible for the secondary growth of plants, leading to an increase in girth. The video script uses the cambium as an example to explain how lateral meristem contributes to the thickening of stems and roots, which is a key aspect of the growth process in woody plants.

Highlights

Plants have two types of tissues: dividing tissues and non-dividing tissues.

Dividing tissues are technically known as meristematic tissues, derived from the Greek word 'meristos' meaning 'divided'.

Meristematic tissues are responsible for cell division and plant growth.

Meristematic tissues are found in areas of the plant that exhibit growth.

Growth in plants is restricted to certain parts, not all parts show growth.

Meristematic tissues are named differently based on their location in the plant.

There are three main types of meristematic tissues in plants.

Apical meristem is found in the growing tips of stems and roots, increasing plant length.

Lateral meristem is associated with the girth or CAMBIUM of the plant, increasing its width.

Intercalary meristem is located at the base of leaves or internodes, facilitating the growth of twigs into branches.

Meristematic tissues are very active and require a lot of energy and nutrients.

At initial stages, meristematic tissues are undifferentiated and perform simple growth functions.

After maturity, meristematic tissues differentiate into components of a single tissue, with division of labor occurring post-maturity.

Characteristics of non-dividing tissues will be studied in the next lesson.

Transcripts

In our last video we studied that plants have

two types of tissues.

Can you name them for me?

What are they called?

Dividing tissues and non-dividing tissues right?

Absolutely correct, now let us look at the

technical terms for these tissues.

In this lesson, we will look at the former

type of tissues.

The dividing tissues in plants are known as

MERISTEMATIC tissues.

Where does the word ‘meristematic’ come from?

It comes from the Greek word

‘meristos’ meaning ‘divided’.

Well, the main function of this tissue is

to divide and help the plant grow.

So where do you think you will find this tissue?

Exactly! They are at all the places where

the plant's parts show growth.

And as we just studied, all the parts of the

plant DO NOT show growth.

Growth is restricted to only certain parts of the plants.

What’s interesting is that meristematic tissues

is named differently based on the part

where it is found.

And do you know how many such parts of plants

have meristematic tissues?

Three different parts.

That’s correct!

Three different parts have meristematic tissues.

The meristematic tissues in each of these parts

has different names.

Let us look at the three main types of meristematic tissues.

The first is the ‘APICAL MERISTEM’,

the second is the ‘LATERAL MERISTEM’

and the third is the ‘INTERCALARY MERISTEM’.

Do not be let down by these difficult names.

Let me make them easy for you to understand.

‘Apical meristem’ tissues are found in

the growing tips of the STEMS and the ROOTS.

This tissue divides and helps increase the

LENGTH of the plant.

What about the second one,

‘Lateral meristem’?

Do you know where it is found in the plant body?

The word lateral means ‘side to side’

and this means the ‘GIRTH’ of the plant.

The ‘lateral meristematic tissue’ divides

and increases the girth of the plant.

‘Apical’ increases the length and ‘lateral’

increases the girth.

This girth of the plant is also known as the

CAMBIUM of the plant.

What about the last tissue type,

Intercalary?

Where is this tissue found?

This tissue is found at the base of the leaves

or the internodes.

These spaces here are known as the nodes.

What do you think this tissue will do?

They will facilitate the growth of the twigs

into branches.

As these tissues are VERY active,

the cells in these tissues are filled with CYTOPLASM.

They require a lot of energy and nutrition

to carry out the various functions of the tissues.

But do you know something interesting?

At the initial stages, these tissues are not

differentiated into any specific types.

Once they divide and mature after completing

the growth of the plant, their characteristics change.

Then they are differentiated into components

of a single tissue.

Division of labour takes place only after maturity.

Until then, all the meristematic tissues exhibit

the same function of ‘simple growth’ of the plant.

If these are the characteristics of the dividing tissues,

what about the non-dividing tissues?

Let us study them in our next lesson.