Question

The primary plant body is made up of (a) Meristematic tissues (b) Simple tissues (c) Complex tissues (d) All the above

Short answer

The correct answer is (d) All the above.

Step-by-step solution

Understand the plant tissue types

There are three types of tissues in plants: Meristematic tissues, Simple tissues, and Complex tissues.

Understand the role of each tissue

Meristematic tissues are responsible for plant growth through cell division; Simple tissues like parenchyma, collenchyma and sclerenchyma have specific functions related to photosynthesis, elasticity and strength respectively; Complex tissues like xylem and phloem transport water and nutrients within the plant.

Combine the understanding

The primary plant body is constructed through the combination of these tissue types, each fulfilling its distinctive role in the plant structure. Therefore, the primary plant body is made up of all the mentioned tissues, i.e., Meristematic, Simple and Complex tissues.

Key concepts

Meristematic Tissues

In the plant world, growth is life, and meristematic tissues are the key players in this process. These special tissues are clusters of cells that are always ready to divide. This continuous cell division allows for the formation of new tissues, which is critical for growth. You can think of them as the plant's growth zones.
Meristematic tissues are typically found in places where plants grow, such as the tips of roots and shoots. These areas are known as apical meristems. There are also lateral meristems that help the plant grow in thickness or girth. A third type, the intercalary meristem, is found in some plants like grasses, allowing regrowth after being cut.

• Meristems have small, undifferentiated cells.
• Their primary role is continuous cell division.
• Located at growth regions - tips, sides, and intercalary sections.

These characteristics make meristematic tissues fundamental to plant development, enabling them to reach sunlight, absorb water, and transport nutrients effectively.

Simple Tissues

Simple tissues consist of only one type of cell, and they play various roles depending on their location and function within the plant. The three main kinds of simple tissues are parenchyma, collenchyma, and sclerenchyma.
Parenchyma cells are the most common type of simple tissue. Known for their thin walls and versatile roles, they are crucial in tasks like storage, photosynthesis, and healing of wounds.

• Thin-walled cells often found in leaves (photosynthesis) and fruits (storage).

Collenchyma cells differ slightly; they have thicker walls which provide support and flexibility. They allow young stems and leaves to bend without breaking.

• Found beneath the epidermis, support growing parts.

Sclerenchyma takes on a more rigid role, with thick walls offering strength and resistance. This makes them important for supporting mature parts of the plant.

• Found as fibers and sclereids, offering rigidity and strength.

Each type of simple tissue is specifically adapted to meet the needs of the plant structure where they reside, balancing support, flexibility, and function.

Complex Tissues

Complex tissues comprise several types of cells, working together to execute complex functions in plants. They form two primary yet intricate systems: xylem and phloem.
The xylem's main role is to transport water and minerals from the roots upwards through the plant. It acts much like a highway system, allowing these vital resources to reach every part of the plant.

• Composed of vessel elements, tracheids, fibers, and parenchyma cells.
• Provides structural support due to its lignified walls.

On the other hand, phloem is responsible for transporting food from the leaves, where it's made during photosynthesis, to other parts of the plant.

• Contains sieve tubes, companion cells, fibers, and parenchyma cells.
• Facilitates the movement of sugars and other metabolic products.

Both xylem and phloem are essential for the plant's survival, as they ensure the efficient distribution of water, nutrients, and food throughout the plant body, preparing it for growth and stability.