Rosales

Key takeaways

Rosales belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Rosales to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Rosales from memory before moving on to harder problems.

Reference excerpt

Rosales (, roh-ZAY-leez) are an order of flowering plants. Well-known members of Rosales include: roses, strawberries, blackberries and raspberries, apples, cherries, pears, plums, peaches and apricots, almonds, rowan and hawthorn, jujube, elms, banyans, figs, mulberries, breadfruit, nettles, hops, and cannabis. Rosales contain about 7,700 species, distributed into nine families and about 260 genera. Their type family is the rose family, Rosaceae. The largest families are Rosaceae (91/4828) and Urticaceae (53/2625).

Taxonomy The order Rosales is strongly supported as monophyletic in phylogenetic analyses of DNA sequences, such as those carried out by members of the Angiosperm Phylogeny Group. In their APG III system of plant classification, they defined Rosales as consisting of the nine families:

Cannabaceae (hemp family) Dirachmaceae Elaeagnaceae (oleaster/Russian olive family) Moraceae (mulberry family) Rhamnaceae (buckthorn family) Rosaceae (rose family) Ulmaceae (elm family) Urticaceae (nettle family)

In the older classification system of Dahlgren the Rosales were in the superorder Rosiflorae (also called Rosanae). In the obsolete Cronquist system, the order Rosales was many times polyphyletic. It consisted of the family Rosaceae and 23 other families that are now placed in various other orders. These families and their placement in the APG III system are:

Alseuosmiaceae (Asterales) Anisophylleaceae (Cucurbitales) Brunelliaceae (Oxalidales) Bruniaceae (Bruniales) Byblidaceae (Lamiales) Cephalotaceae (Oxalidales) Chrysobalanaceae (Malpighiales) Columelliaceae (Bruniales) Connaraceae (Oxalidales) Crassulaceae (Saxifragales) Crossosomataceae (Crossosomatales) Cunoniaceae (Oxalidales) Davidsoniaceae (Cunoniaceae, Oxalidales) Dialypetalanthaceae (Rubiaceae, Gentianales) Eucryphiaceae (Cunoniaceae, Oxalidales) Greyiaceae (Melianthaceae, Geraniales) Grossulariaceae (Saxifragales) Hydrangeaceae (Cornales) Neuradaceae (Malvales) Pittosporaceae (Apiales) Rhabdodendraceae (Caryophyllales) Rosaceae Saxifragaceae (Saxifragales) Surianaceae (Fabales)

Phylogeny The relationships of Rosales families were resolved in a molecular phylogenetic study based on two nuclear genes and ten chloroplast genes:

The order Rosales is divided into three clades that have never been assigned a taxonomic rank. The basal clade consists of the family Rosaceae; another clade consists of four families, including Rhamnaceae; and the third clade consists of the four urticalean families. The order is a sister to a clade consisting of Fagales and Cucurbitales.

Distribution Different plants that fall under the order Rosales grow in many different parts of the world. They can be found in the mountains, the tropics and the arctic. Even though you can find a member of the order Rosales nearly anywhere, the specific families grow in different specific geographical locations. Wind-pollination is the way that the majority of the families that fall under the order Rosales (including Moraceae, Ulmaceae, and Urticaceae etc.) pollinate.

Importance Within the order Rosales is the family Rosaceae, which includes numerous species that are cultivated for their fruit, making this one of the most economically important families of plants. Fruit produced by members of this family include apples, pears, plums, peaches, cherries, almonds, strawberries, blackberries and raspberries. Many ornamental species of plant are also in the family Rosaceae, including the rose after which the family and order were named. The rose, considered a symbol of love in many cultures, is featured prominently in poetry and literature. Modern garden varieties of roses such as hybrid teas, floribunda, and grandifora, originated from complex hybrids of several separate wild species native to different regions of Eurasia. The Moraceae also produce important fruits, such as mulberries, figs, jackfruits, and breadfruits, and the leaves of the mulberry provide food for the silkworms used in commercial silk production. The wood from the black cherry (Prunus serotina) and sweet cherry (P. avium) is used to make high quality furniture due to its color and ability to be bent. The Cannabis plant has been highly prized for millennia for its hemp, which has numerous uses. Other varieties of Cannabis are grown as a drug. Plants in the order Rosales were used in the traditional medicines of many cultures. Medical cannabis has been recognized for its pharmaceutical use. The latex of some species of fig trees contains the enzyme ficin, which is effective in killing roundworms that infect the intestinal tracts of animals.

References

External links Media related to Rosales at Wikimedia Commons Data related to Rosales at Wikispecies Rosales At: Trees At: Angiosperm Phylogeny Website At: Missouri Botanical Garden Website Rosales – Plant Life Forms "Rosales". Integrated Taxonomic Information System. Retrieved 24 April 2008.

Illustrations

Worked examples

Example 1 — a first encounter with Rosales

Start with the simplest possible case. Write down what Rosales claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Rosales before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Rosales ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Rosales

In research: Rosales appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Rosales in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Rosales is common in secondary-school and first-year university syllabi. It links to neighbouring topics Angiosperm orders, Rosales, so understanding it makes those chapters shorter.
In everyday life: Look for Rosales outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

How to study Rosales in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Rosales means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Rosales out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Rosales in simple terms?

Rosales (, roh-ZAY-leez) are an order of flowering plants. Well-known members of Rosales include: roses, strawberries, blackberries and raspberries, apples, cherries, pears, plums, peaches and apricots, almonds, rowan and hawthorn, jujube, elms, banyans, figs, mulberries, breadfruit, nettles, hops…

Why does Rosales matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Rosales?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Rosales.