Write the various components of the shoot system of a plant.
What is meant by leaf venation. Name the various types of le
Answers
The Structure of the Shoot System
A plant has many complicated and complex systems that keep it living and growing, including the shoot system. When referring to the shoot system in a plant, we generally refer to the leaves, buds, flowering stems and flowering buds, as well as the main stem itself. The word 'shoot' generally is used when talking about the main stem.
As we move from the ground surface to the terminal bud (end of the undeveloped shoot) we will encounter nodes and internodes. Nodes are the points where leaves are attached, and internodes are the places on the stem between the nodes. In the crux created by the node and stem, there are axillary buds that lay dormant but have the potential to grow a vegetative branch.
Plant Shoot System
Shoot System
These axillary buds lay dormant because of apical dominance. This is a phenomena where the plant concentrates most of its resources at the terminal bud. The terminal buds grows at the apex, or tip of the plant. This is responsible for making the plant grow taller and bigger so it makes sense that the plant would want to concentrate resources here. If the terminal bud gets damaged, the axillary buds will 'wake up' and begin to grow, saving the plant.
If the axillary buds begin to grow, they can create their own terminal buds, leaves, etc. They, in a sense, create a secondary plant themselves. If you own any houseplants, you might understand the idea of pruning them to create 'bushy' plants. Well, this is because you are removing the terminal bud that stimulates the axillary buds to grow, creating that thicker looking plant.
As is commonly known, the leaves of the plant act as the photosynthetic factory for it, producing sugars and other compounds for the plant to survive on. There are many different types of leaves, but most will include a blade, stalk, veins and the petiole. The stalk is the main stem of the leaf, the blade is the actual green leaf portion, and the petiole is where it attaches to the node. The veins are similar to our veins in that they carry water and nutrients out into the leaf.