For each of the following questions, four choices have been provided. Select the correct alternatives. Match the following A Sweet potato i Stem B Potato ii Bulb C Onion iii Root D Scion iv Graft \(\begin{array}{lll}\mathbf{B} & \mathbf{C} & \mathbf{D}\end{array}\) \(\begin{array}{lll}\mathbf{A} & \mathbf{B} & \mathbf{C}\end{array}\) \(\begin{array}{llll}\text { (a) iii ii } & \text { ii }\end{array}\) (b) \(\mathrm{i}\) ii iii iv \(\begin{array}{llll}\text { (c) iii } & \text { i } & \text { ii } & \text { iv }\end{array}\) (d) ii \(\mathrm{i}\) iv iii

Plants have evolved various adaptations to survive in different environments, and one fascinating example is modified stems.
Normally, when we think of stems, we imagine the rigid structure holding up leaves and flowers, but modified stems, such as tubers and bulbs, serve additional functions.

• Tubers - The potato is a classic example of a tuber. Tubers are enlarged structures in some plant species that are used to store nutrients. The potato's 'eyes' are actually buds that can sprout into new plants!
• Bulbs - Onions are well-known bulbs. Bulbs have a short stem with fleshy leaves or leaf bases that store food during dormancy.

Understanding the purpose of these modifications aids in identifying how plants like sweet potatoes and onions grow and reproduce.

Just like animals, plants also have ways to ensure their species thrive through reproduction. There are two primary methods:
Sexual reproduction involves the fusion of male and female gametes, resulting in genetically diverse offspring. This can occur through pollination in flowers where seeds are produced.

Asexual reproduction is where a new plant grows from a part of the parent plant without the need for seeds. This includes budding from tubers or sprouting from bulbs.

• Advantages of asexual reproduction include the rapid spread and the creation of uniform offspring, ideal for plants like potatoes and onions which use modified stems to replicate.

In our exercise, understanding these mechanisms helps explain why certain plant parts are associated with reproduction, even when it's not obvious through flowering or seed production.

Grafting is a horticultural technique used to join parts from two plants so that they grow as one. The part of the plant that is attached is called the scion, and it typically includes the stems, leaves, or flowers that possess desired traits. The plant it is attached to is the rootstock, which provides the root system.

• Purpose: Grafting is often done to reproduce fruit trees more reliably, combining the best qualities of two different plants.

Grafting requires precise technique and understanding, making it an advanced aspect of plant reproduction - it's a marvelous example of human intervention to enhance or modify natural plant processes. In the context of our exercise, recognizing grafting is crucial to determining how the plant part labeled 'scion' fits into the broader category of plant propagation methods.