Name the labelled 'x' in plant
Thorn is a sharp pointed modified stem. Stem thorns are stiff sharp short structures present on the stem. These are modified stems and arise from buds. Thorns serve two purposes, the rescue transpiration and check on browsing by animals.
Thorns are present on axillary stems of a plant, examples of plants that have thorns are Citrus, Duranta, Bougainvillaea.
Spines is a sharp pointed structure that is a modified leaf or stipule.
Prickles are sharp outgrowth arising from the bark.Prickles arise from stem tissue and are extensions of its cortex and epidermis. Rose prickles serve to keep away predators.
Prickles are notable for their complete absence of vascular tissue, the microscopic vessels that conduct sugar and water throughout a plant. Since prickles are sharp projections produced by the skin of a plant, they tend to pop off easily, as they do on rose bushes.
Hooks are the leaf modification where the end of the leaflets develops a hook-like structure which gives the plants support and helps them in climbing, it is mostly observed in the case of the flowering plants.