what are plant spines

Full Answer

What are the spines of a plant called?

Spines. Spines are modified leaves, stipules, or parts of leaves, such as extensions of leaf veins. Some authors prefer not to distinguish spines from thorns because, like thorns, and unlike prickles, they commonly contain vascular tissue. Spines are variously described as petiolar spines (as in Fouquieria ), leaflet spines (as in Phoenix ), or ...

What is a spinescent plant?

Spinescent is a term describing plants that bear any sharp structures that deter herbivory. It also can refer to the state of tending to be or become spiny in some sense or degree, as in: "... the division of the African acacias on the basis of spinescent stipules versus non-spinescent stipules..."

Why do plants have spines on their leaves?

Although it has been shown that in some plant families, such as cacti, spines arose primarily as a mechanism to reduce water loss from leaves, most plants that have spines use them to protect themselves from hungry animals.

What kind of plants have thorns and spines?

Plants with thorns, spines and prickles. Plants with prickles, spines and thorns should always be handled with a bit more care than your typical house plant. Well-known examples include aloe, rose bush and thistles.

What are spines of a plant?

Spine: a firm, slender, sharp-pointed structure, representing a modified leaf or stipule (a stipule is an appendage found at the base of a petiole, i.e., at the base of a leaf's stalk). Thorn: a stiff, woody, modified stem with a sharp point.

What are spines in biology?

[countable] the row of bones down the centre of your back that supports your body and protects your spinal cord SYN backbone, → spinal2 [countable] a stiff sharp point on an animal or plant → spiny cactus spines3 [countable] the part of a book that the pages are fastened onto4 [uncountable] courage or determination ...

What is a leaf spine plant?

The spine is technically a modified, sharp-pointed leaf. Since it has a bud in its axil, the spine occurs in the relative position of a leaf. Some spines are called "stipular spines" because they are modified, sharp-pointed stipules at the base of a leaf.

What are leaf spines answer?

In certain plants entire or the parts of the leaves are modified into sharp and pointed structure called as leaf spines. They are exogenous in origin. It can act as defensive structure since it can protect the plants against grazing animals. It also reduces transpiration.

What are spines used for?

Your spine, or backbone, is your body's central support structure. It connects different parts of your musculoskeletal system. Your spine helps you sit, stand, walk, twist and bend. Back injuries, spinal cord conditions and other problems can damage the spine and cause back pain.

How do spines protect plants?

The presence of spines on woody plants has been shown to limit the loss of foliage to large mammalian browsers by restricting both bite size and biting rate.

What are spines on a cactus?

The spines of cacti are actually modified leaves. It helps to imagine cacti as large stems with spines for leaves.

How do plants grow spines?

It turns out that spines are derived from leaf tissue and thorns from stem tissue. Prickles come from neither; they are simply corky projections from a plant's skin, or dermal tissue. Plant anatomy comes into play here, as the internal structure of leaves, stems, and roots are unique in their arrangement.

Why are cactus spines?

By shading the cactus, these spines also help prevent the cactus from losing water through evaporation. So all in all, spines are adaptations that protect and help cacti hide from animals that may want to eat them. They also provide shade for the plant, which keeps them cooler and limits water loss.

Are thorns spines?

Spine – A sharp pointed structure that is a modified leaf or stipule. Prickle – A sharp outgrowth from the epidermis or bark. A thorn is a modified stem and can be recognized because it is subtended by a leaf. Thorns may be branched or un-branched.

What are the functions of spines of leaves?

Spines: leaves or part of leaves get modified into pointed structures called spines. Spines help to reduce the loss of water by transpiration.

How are spines different from leaves?

Spines are structures that are sharp in nature and are pointed. They are part of the plant and are modified leaves....What is the Difference between Thorns and Pickles?CriteriaSpinesThornsPart of the plantSpines are modified leaves or part of leavesThorns are modified branches5 more rows

What is spinescent plant?

Spinescent is a term describing plants that bear any sharp structures that deter herbivory. It also can refer to the state of tending to be or become spiny in some sense or degree, as in: "... the division of the African acacias on the basis of spinescent stipules versus non-spinescent stipules...".

What do short root spines cover?

Short root spines cover the tuberous base of the epiphytic ant-plant Myrmecodia tuberosa (Rubiaceae), these probably give protection to ants which inhabit chambers within the tuber as they wander over the plant's surface. (Jackson 1986 and references therein).

What is the epidermis of a leaf called?

When the leaf epidermis is covered with very long, stiff trichomes (more correctly called bristles in this case; for some authors a kind of prickle ), it may be referred to as a hispid vestiture; if the trichomes are stinging trichomes, it may be called a urent vestiture.

What is the function of thorns, prickles, and thorns?

The predominant function of thorns, spines, and prickles is deterring herbivory in a mechanical form. For this reason, they are classified as physical or mechanical defenses, as opposed to chemical defenses. Not all functions of spines or glochids are limited to defense from physical attacks by herbivores and other animals.

Where do thorns come from?

In common language the terms are used more or less interchangeably, but in botanical terms, thorns are derived from shoots (so that they may or may not be branched, they may or may not have leaves, and they may or may not arise from a bud), spines are derived from leaves (either the entire leaf or some part of the leaf that has vascular bundles inside, like the petiole or a stipule ), and prickles are derived from epidermis tissue (so that they can be found anywhere on the plant and do not have vascular bundles inside ).

What are thorns, spines, and prickles?

In plant morphology, thorns, spines, and prickles, and in general spinose structures (sometimes called spinose teeth or spinose apical processes ), are hard, rigid extensions or modifications of leaves, roots, stems or buds with sharp, stiff ends, and generally serve the same function: physically deterring animals ...

What are some examples of plants that have thorns?

Examples include hawthorn hedges in Europe, agaves in the Americas and in other countries where they have been introduced, Osage orange in the prairie states of the US, and Sansevieria in Africa.

Why do plants have spines?

Although it has been shown that in some plant families, such as cacti, spines arose primarily as a mechanism to reduce water loss from leaves, most plants that have spines use them to protect themselves from hungry animals.

Where do spines come from?

It turns out that spines are derived from leaf tissue and thorns from stem tissue. Prickles come from neither; they are simply corky projections from a plant’s skin, or dermal tissue. Plant anatomy comes into play here, as the internal structure of leaves, stems, and roots are unique in their arrangement. This opens in a new window.

What is the name of the tree with prickles?

The stem of Ceiba insignis (silk floss tree), in the Desert Garden, showing bark with prickles. Photo by Sean Lahmeyer. Spines, the ones derived from leaves, show many variations worthy of note. Some spines, like those in the Fouquieria family (think of an Ocotillo plant from the Mojave Desert), are derived from leaf stalks.

Do thorns have a hardened outer dermal layer?

Their thorns have a hardened outer dermal layer, instead of a stronger internal core, such as wood would provide. A comparison can be drawn to the hard coating, or exoskeleton, of an insect versus the bone, or endoskeleton, of a vertebrate animal—they are both adaptations for structural strength.

Do cacti have spines?

Acacia trees (in the bean family) have spines made of modified leaf stipules. There are also plants whose entire leaves have been converted into spines, as is the case with cacti. All of these spines are dead at maturity, full of fibers, and no longer capable of photosynthesis.

Does Cryosophila albida have a stem?

Indeed, a closer look under the microscope confirmed that the spiny structures on the stem of Cryosophila albida have the internal anatomy of a root, not a stem. Cross section of a Cryosophila albida root spine, with the addition of methylene blue dye for contrast. The internal anatomy matches that of a root, not a stem.

Which flowering plant has white spines?

Fever Tree – The Acacia xanthophloea has large white spines that grow in pairs along its branches, protecting its delicate cream flowers. Rose – One of the most popular flowering plants in the world; there are over 100 species of rose available today. The majority of varieties have prickles along their stems and branches.

What plants have thorns?

The most popular plants with thorns or spines on in the UK are: 1 Citrus – Citrus trees that grow in the wild often produce thorns to keep away hungry animals from their fruit. The ones you find in garden centres have typically been cultivated to grow without thorns. 2 Fever Tree – The Acacia xanthophloea has large white spines that grow in pairs along its branches, protecting its delicate cream flowers. 3 Rose – One of the most popular flowering plants in the world; there are over 100 species of rose available today. The majority of varieties have prickles along their stems and branches.

What are thorns on a plant?

Typically, thorns are modified branches that are attached to the trunk or stem of a plant. Prickles are not remnants of any existing part of the plant and are typically found on the leaf structure, stem or ‘skin’ of the plant. The most popular plants with thorns or spines on in the UK are: Citrus – Citrus trees that grow in ...

Thorns

The thorns are modified branches of a plant that are woody & pointed. They occur in the axil of a leaf where a branch is developed. They help plants in climbing. Thorns are axillary leaves of a plant. They are subtended by a leaf. They are defensive organs of plants that help plants in rising and protecting them from animals.

Spines

The spines are the modified leaf of a plant with a sharp and pointed structure. They need in a comparative position of a leaf. They protect plants from herbivores and some other animals they cover and protect the plants and also protect plants from outrageous temperatures. They also have a vascular bundle inside them.

Difference between Thorns and Spines

Thorns and spines are very similar to each other so it is a little tough to differentiate between them. But they are not the same. There are so many things that make a difference between thorns and spines. They both have a vascular bundle. They both have a pointed structure. They both prevent plants.

Plants with Thorns

There are so many plants that have thorns. Plants with thorns are called thorny plants. They will prevent your house as well but be careful when planting them. Keep children & your pets away from it.

Plants with Spines

Just like thorns, some plants have Spines. The spines are like the leaves of plants. They are sharp and pointed. Most of the spines trees are found in the cacti family. These spines protect the plant stems.

Things to Remember

Thorns are woody, pointed structures of plants that protect the plant and help in climbing.

Sample Questions

Ans: Thorns are the modification of the axillary shoot system of the plants in which the leaves of the plants are reduced so they die quickly & due to this the stems of plants are heavily clarified & grow only for a fixed limited time. Thorns help the plants to grow & they prevent them from dangerous animals.

Why do holly trees have spines?

Meanwhile, the highest branches of mature holly trees completely lack the sharp appendages. These spines actually explain the plant's connection to Christmas. Originally, in pre-Christian times, pagans used the plants to ward off evil spirits and to celebrate the Winter Solstice Festival.

What is an agave plant?

Agave is a genus of plants that includes many species of succulents that live in hot and arid conditions. These plants have adapted to their desert homes with various features, including spikes. In this case, the spines poke out at predators to deter them from using the leaves as a water source.

Do spiny plants protect property lines?

Spiny plants can be a hassle for maintenance and pruning, but when it comes to your personal home security, these masters of pain handily defend property lines and first-floor windows. 🌳 Nature is badass. Let's nerd out over our world together. As a bonus, most of the plants trick themselves out with delicate blossoms in spring ...

Bull Thistle (Cirsium vulgare)

Of all the spiky weeds, thistles are probably the most recognizable. Bull thistles have spines that cover the leaves and stems of the weed up to the pink-purple flowers. They also have spiny bracts that grow beneath the flower head.

Jimson Weed (Datura stramonium)

Jimson weed is an invasive weed that’s a member of the nightshade family. It’s also known as thorn apple and devil’s snare.

Prickly Sida (Sida spinosa)

Does the weed have a spike at its leaf nodes? If the answer’s yes, then you might be looking at prickly sida.

Carolina horsenettle (Solanum carolinense)

Also called devil’s tomato, horsenettle is part of the nightshade family. The weed produces fruit that resemble small tomatoes. But be warned, horsenettle is a poisonous weed and the fruit is toxic to eat. Just handling the plant causes a rash for some people.

Common Cocklebur (Xanthium strumarium)

Common cocklebur has spines on its fruit. When the weed is mature, each fruit, called a bur, is about 2.5 cm long and covered with hook-shaped spines. The prickly burs easily hook onto your clothing or the fur of animals.

Goat Head Weed (Tribulus terrestris)

Goat head weed is also called devil’s thorn, puncturevine, and bindii. It’s notorious for the sharp barbs on its fruit. These vertical spikes resemble horns, and easily puncture thin shoes, bare feet, bicycle tires, and the hooves of animals. This allows the seeds to be carried to new locations. And so the plant spreads.

Lawn Burweed (Soliva sessilis)

One of the pleasures of having a lawn is feeling the grass under your bare feet. But you better be careful if lawn burweed is in your yard. This weed disperses prickly thorn balls that will give you a nasty surprise.

Overview

In plant morphology, thorns, spines, and prickles, and in general spinose structures (sometimes called spinose teeth or spinose apical processes), are hard, rigid extensions or modifications of leaves, roots, stems or buds with sharp, stiff ends, and generally serve the same function: physically deterring animals from eating the plant material.

Description

Function

Definitions and technical distinctions

Evolution

Morphological variation

Human uses

See also