Question

Stems modified into flat green organs performing the functions of leaves are known as
A. Cladodes
B. Phyllodes
C. Phylloclades
D. Scales

Answer 1

Hint: Stem transports water, minerals, and food to other parts of the plant body through various systems. In some plants, the stem is modified to perform other functions such as reservoir of food, support, vegetative propagation and protection.

Complete Answer:
To answer this question, first, we need to know about plant stem modification. The stem is the part of the plant that provides support and helps in conduction.

In a few plants, the stem is changed for some other functions like-
1. Stem modification below the soil- In this type of change, stems remain under the soil and store the large quantities of food e.g., potato, ginger etc.
2. Sub-aerial modification- In this kind of modification, weak stems lie straightly on the ground and form adventitious roots that support in vegetative propagation e.g., grass, pumpkin etc.
3. Aerial stem modification- in such modification, axillary buds are modified to throne and tendril for protection and support e.g., rose, pea etc.

Now, let us find the solution from the option.
- Cladode is a flattened organ arising from the stem of a plant.
- Phyllodes are rare breast tumors that start in the connective (stromal) tissue of the breast.
- Phylloclades are a flattened, photosynthetic branch or stem that resembles or performs the function of a leaf.
- Scale sounds and looks a lot like a plant disease, but the term actually refers to infestation by any one of more than 7,000 species of tiny sap-sucking insects.

Thus, the correct option is C. i.e. Phylloclades.

Note: Stems are changed to take part in many functions within the plant body. For example, aerial stem changing thorns manage transpiration and keep the release of water from the plant body in check. Their major function is protecting the plant from external injury.