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Bract
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Papery (upper) and leafy bracts on hay rattle (
Rhinanthus minor). All the "leaves" in this image are bracts.
In
botany, a bract is a modified or specialized
leaf, especially one associated with a reproductive structure such as a
flower,
inflorescence axis, or
cone scale. Bracts are often (but not always) different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture. Typically, they also look different from the parts of the flower, such as the petals and/or sepals.
Some bracts are brightly colored and serve the function of attracting pollinators, either together with the
perianth or instead of it. Examples of this type of bract include
Euphorbia pulcherrima (poinsettia) and
Bougainvillea: both of these have large colourful bracts surrounding much smaller, less colourful flowers.
In grasses, each floret (flower) is enclosed in a pair of papery bracts, called the lemma (lower bract) and palea (upper bract), while each spikelet (group of florets) has a further pair of bracts at its base called glumes. These bracts form the
chaff removed from
cereal grain during
threshing and
winnowing.
Bats may detect acoustic signals from dish shaped bracts s...
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