Editing Homology (biology) (section)

====Leaves, stems and roots====
In many plants, defensive or storage structures are made by modifications of the development of primary [[leaves]], [[plant stem|stems]] and [[root]]s. Leaves are variously modified from [[photosynthetic]] structures to form the insect-trapping pitchers of [[pitcher plants]], the insect-trapping jaws of the [[Venus flytrap]], and the spines of [[cacti]], all homologous.<ref>{{cite web |title=Homology: Leave it to the plants |url=http://evolution.berkeley.edu/evolibrary/article/homology_01 |publisher=University of California at Berkeley |access-date=7 May 2017}}</ref>

{| class="wikitable"
|-
! Primary organs
! Defensive structures
! Storage structures
|-
| Leaves
| [[Thorns, spines, and prickles|Spines]]
| Swollen leaves (e.g. [[succulents]])
|-
| Stems
| [[Thorns, spines, and prickles|Thorns]]
| Tubers (e.g. [[potato]]), rhizomes (e.g. [[ginger]]), fleshy stems (e.g. [[cacti]])
|-
| Roots
| -
| Root tubers (e.g. [[sweet potato]]), taproot (e.g. [[carrot]])
|}

Certain [[compound leaf|compound leaves]] of flowering plants are partially homologous both to leaves and shoots, because their [[evolutionary developmental biology|development has evolved]] from a [[mosaic (genetics)|genetic mosaic]] of leaf and shoot development.<ref>{{cite journal |last=Sattler, R. |title=Homology — a continuing challenge |journal=Systematic Botany |volume=9 |pages=382–394 |year=1984 |doi=10.2307/2418787 |issue=4 |jstor=2418787}}</ref><ref>{{cite book |last=Sattler, R. |chapter=Homology, homeosis, and process morphology in plants |editor=Hall, Brian Keith |title=Homology: the hierarchical basis of comparative biology |publisher=Academic Press |year=1994 |pages=423–75 |isbn=978-0-12-319583-8 }}</ref>

<gallery mode="packed">
File:EurAshLeaf.jpg|One [[pinnate]] leaf of [[European ash]]
File:Detail on a palm frond (8297623365).jpg|Detail of [[palm (plant)|palm]] leaf
File:Ocotillothron02262006.JPG|Leaf [[petiole (botany)|petioles]] adapted as [[Thorns, spines, and prickles|spines]] in ''[[Fouquieria splendens]]''
File:Musa acuminata Gran Canaria 2.JPG|The very large leaves of the banana, ''[[Musa acuminata]]''
File:Split Aloe.jpg|Succulent water [[storage organ|storage]] leaf of ''[[Aloe]]''
File:Venus Flytrap showing trigger hairs.jpg|Insect-trapping leaf of a [[Venus flytrap]]
File:Nepenthes muluensis.jpg|Insect-trapping leaf of [[pitcher plant]]
File:Onions 002.jpg|Food storage leaves in an [[onion]] [[bulb]]
</gallery>