الفرق بين spins وprickles لطلبة علوم

Explain the difference between thorns, spines, and prickles.?
Thorns Spines and Prickles have only one thing in common viz. they are all very sharp pointed and helpful as a defense mechanism.

Now let us see the differences ( All Botanical)

1) Spines = these are all modified LEAVES; i.e. the leaves are turned in to or reduced to spines. Very good example is Cactus. In all cacti the stem does the function of photosynthesis (Phylloclade) and the leaves are turned in to spines to reduce the rate of transpiration and also act as defense mechanism against animals.They are seen at the node where a leaf is expected

2) Thorns = These are all modified branches ( i.e. stem modification). They either develop from terminal or axillary buds.. They are also used for defense.They are seen only at the node of the plant.They are endogenous in origin i.e. from the vascular tissue.Examples are Pomegranate, Bougainvillea

3) Prickles = These are NOT modifications of any existing organ of a plant. They are entirely new organs ( "Organa de novo" as said in Latin).They are found any where and indiscriminately on the plant( Stem , leaves ) . They are exogenous in origin ( develop from epidermal tissue only). Therefore they break off easily. Rose is an excellent example.
Source(s):
From A Botanist of Repute.

جزاك الله خيرا والله
مع انى مفهمتش ولا كلمه