Arabidopsis thaliana

Arabidopsis thaliana (syn. Arabis thaliana L.; thale cress or mouse-ear cress, also arabidopsis), is a species of Arabidopsis, native to Europe, Asia, and northwestern Africa, from the British Isles south to the Azores and Morocco, east to Japan, and southeast to northern India.It is an annual (rarely biennial) plant growing to 5–30 cm (rarely to 50 cm) tall. The leaves form a rosette at the base of the plant, with a few leaves also on the flowering stem. The basal leaves are green to slightly purplish in colour, 1.5–5 cm long and 2–10 mm broad, with an entire to coarsely serrated margin; the stem leaves are smaller, unstalked, usually with an entire margin. Both leaves and stems are thinly hairy, with 1 mm stellate hairs. The flowers are 3 mm in diameter, arranged in a corymb; their structure is that of the typical Brassicacaea. The fruit is a siliqua 5–20 mm long, containing 20–30 seeds. It has a chromosome number of 2n = 10.
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Noun
1. a small invasive self-pollinating weed with small white flowers; much studied by plant geneticists; the first higher plant whose complete genome sequence was described
(synonym) mouse-ear cress
(hypernym) cress, cress plant

A small member of the mustard family (kitchen cress). It has a very small genome (130-140 Mbp), five chromosomes and contains almost no repetitive DNA. Its genome will be completely sequenced by the end of 2000. It is a plant model system of choice because of the additional advantages of short generation time (about five weeks), high seed production (up to 40,000 seeds per plant) and natural self-pollination (as opposed to natural cross-pollination in maize). It has five small chromosomes. Link to Arabidopsis website.