What is the function of thorns? Cactus spines are also known as modified bud scales, which also are modified leaves. Thus, spines lose less water and … Cactus spines occur in clusters in the axil of leaves. The leaf-apex in date-palm, dagger plant (Yucca) etc., is so modified, while in plants like prickly or Mexican poppy (Argemone), Amercian aloe (Agave), Indian aloe (Aloe), etc., spines develop on the margin as well as at the apex. The spine primordia is produced at the base of the axillary bud's shoot apical meristem; the … A group of spines is termed an areole. Most cactus morphologists have concluded that cactus spines are either modified leaves or modified bud scales (the difference is inconsequential because bud scales themselves are modified leaves). honeylocust. above-ground roots arising from the stem that can grow through the air and extend down into the soil ~provide extra absorptive capacity and anchorage/stability for the plant ... What kind of modified stem are thorns? Leaves are modified into spines : Opuntia Stem has sharp thorns : _______ These new leaves were good at two things: avoiding water loss and protecting the plant (On this topic, I wrote a post on why cacti adapted to have spines instead of leaves). Leaves modified for Reproduction: Typically, leaves are determinately growthed. 2 ... Answer: Spines are modified leaves which have less surface area. Tendrils: In peas the terminal leaflet of the leaf has become modified into a tendril for climbing. Plants lose water through their leaves. Cactus spines are modified 1) LEAVES. Soft, broad leaves might be good at photosynthesis, but they lose a lot of water due to evaporation. Those cactus plants that have modified leaves have them as thorns, spines, spikes, quills, prongs or bristles. Cacti have adapted to the harsh conditions they live in by developing areoles instead of branches and spines instead of leaves. 6. Thus, in prickly pear (Opuntia; fig. The grow, function and then die without sustaining new growth. Why leaves of desert plants are modified into thorns? Main menu Back Next Back to vegetative parts main menu Back to stem and leaf modification menu Over time, cacti modified them into clusters of sharp spines or hairs. Ma'am as in the class we have studied the venation of leaves so in cactus as you know that the leaves are modified into spines or thorns so for example i am explaing a child that the leaves having parallel venation will have fibrous roots and the leaves having reticulate - Science - Getting to Know Plants Cactus spines are actually heavily modified leaves, although they don’t have any of the same structures that are found in normal leaves and are completely inert. In deserts, that is something that plants should avoid, so that they can store water. 4.25) the minute leaves of the axillary bud are modified into spines. 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